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Products => Test Equipment => Topic started by: Sherlock Holmes on December 12, 2022, 08:49:59 pm

Title: True analog scopes
Post by: Sherlock Holmes on December 12, 2022, 08:49:59 pm
Do true analog scopes still get produced? is there a market for them or specialized applications for which a digital scops is not suitable? I suppose too that a true analog scope couldn't really use a digital display unless the resolution of the screen was huge and that in turn implies there'd need to be some kind of A/D conversion involved, so it wouldn't be true analog scope...
Title: Re: True analog scopes
Post by: tautech on December 12, 2022, 09:07:51 pm
Do true analog scopes still get produced?
Of course they do and mainly in Asia but who on earth would want one ?  :-//
Their days are long gone.
Title: Re: True analog scopes
Post by: sweatybetty on December 12, 2022, 09:31:12 pm
B&K still lists one.

https://www.bkprecision.com/products/oscilloscopes/2120C (https://www.bkprecision.com/products/oscilloscopes/2120C)

https://www.mouser.com/ProductDetail/BK-Precision/2120C?qs=dOK1vf2izjtMw5LfHj6p4w%3D%3D (https://www.mouser.com/ProductDetail/BK-Precision/2120C?qs=dOK1vf2izjtMw5LfHj6p4w%3D%3D)
Title: Re: True analog scopes
Post by: tautech on December 12, 2022, 09:45:52 pm
B&K still lists one.
Probably a rebrand like many of their products.

If you must there's 14 of these outdated things here:
http://www.pintek.com.tw/productClassify/landersound-tail2/index/16856 (http://www.pintek.com.tw/productClassify/landersound-tail2/index/16856)
Title: Re: True analog scopes
Post by: Sherlock Holmes on December 12, 2022, 09:59:30 pm
Do true analog scopes still get produced?
Of course they do and mainly in Asia but who on earth would want one ?  :-//
Their days are long gone.

Well, there's zero quantization noise, so I was wandering if some applications find that important?
Title: Re: True analog scopes
Post by: tautech on December 12, 2022, 10:04:47 pm
Do true analog scopes still get produced?
Of course they do and mainly in Asia but who on earth would want one ?  :-//
Their days are long gone.

Well, there's zero quantization noise, so I was wandering if some applications find that important?
There's 12 bit DSO's available too.
Guess which kicks arse.  ;)
Title: Re: True analog scopes
Post by: TimFox on December 12, 2022, 10:09:40 pm
X vs Y
Title: Re: True analog scopes
Post by: sweatybetty on December 12, 2022, 10:12:16 pm
Myself, I prefer analog stuff. Simple, easy to use.
I do have a digital frequency generator that is a pita to use. Wading through menus and pushing six different buttons to get something to do what I want is not my idea of fun
My dos centavos  :-+
Title: Re: True analog scopes
Post by: tautech on December 13, 2022, 12:34:50 am
X vs Y
Play or work ?
Title: Re: True analog scopes
Post by: jonpaul on December 13, 2022, 01:16:10 am
have Tektronix scopes since 1970, in Paris Hameg

Paid €5, 25 in Paris at fleas

Look for local Ham radio Fleas, or estate sales, or silent key.

They are easy to fix and made in USA or EU not China

Jon
Title: Re: True analog scopes
Post by: tautech on December 13, 2022, 01:37:17 am
They are easy to fix and made in USA or EU not China
They are, but not for the amateur.

Few even have meters that are capable of measuring EHT and there is always the requirement for a second scope just to fix your main scope.
Stuff that, been there done that and it robbed so much of my hobby time instead of getting on with the enjoyment of it.
Now I sell reliable instruments to those that want to pursue their hobby with a minimum of headaches.
You from another age would do well to take a modern instrument under your wing and actually realise how far the Chinese have come.
Title: Re: True analog scopes
Post by: xrunner on December 13, 2022, 01:52:21 am
They are easy to fix and made in USA or EU not China
They are, but not for the amateur.

Few even have meters that are capable of measuring EHT and there is always the requirement for a second scope just to fix your main scope.
Stuff that, been there done that and it robbed so much of my hobby time instead of getting on with the enjoyment of it.
Now I sell reliable instruments to those that want to pursue their hobby with a minimum for headache.
You from another age would do well to take a modern instrument under your wing and actually realise how far the Chinese have come.

Well I'm going to try a Siglent you might be interested to know - a Siglent SDS1104X-U. Let's see what the experience brings. Will let you know.  :)
Title: Re: True analog scopes
Post by: tautech on December 13, 2022, 02:22:10 am
Well I'm going to try a Siglent you might be interested to know - a Siglent SDS1104X-U. Let's see what the experience brings. Will let you know.  :)
Please do.
Those are an entry level 4ch with just a basic feature set and I thought we'd sell more of them than we do however the 4ch X-E are still #1 for us as buyers seem happier to spend a little more for the somewhat better feature set.
YMMV
Title: Re: True analog scopes
Post by: jonpaul on December 13, 2022, 02:28:36 am
We have used many fine digital scopes available from USA, EU, Japan,
tektronix, HP, Yokogawa, Le Roy.

The OP asked about analog scopes.

I am unaware of any Chinese made CRT scopes.



Just the ramblings of an old retired EE

Jon
Title: Re: True analog scopes
Post by: med6753 on December 13, 2022, 02:58:11 am
Do true analog scopes still get produced?
Of course they do and mainly in Asia but who on earth would want one ?  :-//
Their days are long gone.

Speak for yourself.  :P :P :-DD

(https://imagizer.imageshack.com/v2/xq90/924/Au9QZf.jpg) (https://imageshack.com/i/poAu9QZfj)
Title: Re: True analog scopes
Post by: tautech on December 13, 2022, 03:04:53 am
I am unaware of any Chinese made CRT scopes.
Ask the Chinese if the Taiwanese CRO's I linked earlier are not made in China.  >:D

Maybe you need ask Mr Google:
https://www.made-in-china.com/products-search/hot-china-products/Analog_Oscilloscope.html (https://www.made-in-china.com/products-search/hot-china-products/Analog_Oscilloscope.html)
Title: Re: True analog scopes
Post by: tautech on December 13, 2022, 03:07:55 am
Speak for yourself.  :P :P :-DD
:-DD
Says he whom owns a modern DSO to use as a sanity check of his ancient CRO's.  :P

How are you buddy, is that probe I sent you still working OK on that mini Tek you have ?
Title: Re: True analog scopes
Post by: med6753 on December 13, 2022, 03:33:17 am
Speak for yourself.  :P :P :-DD
:-DD
Says he whom owns a modern DSO to use as a sanity check of his ancient CRO's.  :P

How are you buddy, is that probe I sent you still working OK on that mini Tek you have ?

Of course I embrace new tech where it makes sense. But don't discount the old stuff.  ;D

That probe works a treat. Thanks.  :-+
Title: Re: True analog scopes
Post by: vk6zgo on December 13, 2022, 05:58:53 am
For a brief, shining moment, when the $A was above parity with the $US, a new DSO was affordable for those of us on a restricted budget, but these days, we are confronted with things like a SDS-1102DL+ for $A598.00 plus GST.

https://www.wavecom.com.au/product_view.php?id_product=1035&gclid=CjwKCAiAv9ucBhBXEiwA6N8nYE8M2VLDpCwIWvijQbOtvdgxNkJWnPk-W3c (https://www.wavecom.com.au/product_view.php?id_product=1035&gclid=CjwKCAiAv9ucBhBXEiwA6N8nYE8M2VLDpCwIWvijQbOtvdgxNkJWnPk-W3c)

or a DS1052E for $A429.00 plus GST. at EMONA

Even a Digitech/El Crappo from Jaycar is $A549.00 GST included.
They do have a 25MHz toy for a more affordable $A239.20 GST incl.

On ebay there are some Hantek, Owon, & FNIRSI things at around $A300.00, but I'm dubious about them.
Rigols & Siglents are not much different than buying locally.

Even ancient TDS210s & 220s are around $A300.00 & upwards.

I guess I will have to fix my Tek 7613!
Title: Re: True analog scopes
Post by: tautech on December 13, 2022, 09:16:18 am
For a brief, shining moment, when the $A was above parity with the $US, a new DSO was affordable for those of us on a restricted budget, but these days, we are confronted with things like a SDS-1102DL+ for $A598.00 plus GST.

https://www.wavecom.com.au/product_view.php?id_product=1035&gclid=CjwKCAiAv9ucBhBXEiwA6N8nYE8M2VLDpCwIWvijQbOtvdgxNkJWnPk-W3c (https://www.wavecom.com.au/product_view.php?id_product=1035&gclid=CjwKCAiAv9ucBhBXEiwA6N8nYE8M2VLDpCwIWvijQbOtvdgxNkJWnPk-W3c)
Wow, Wavecom are really taking the piss !  :P
$100 + GST cheaper for the same 100 MHz 2ch model at the Oz master importers Trio:
https://www.triotest.com.au/brands/siglent/digital-oscilloscopes/sds1000dl-series (https://www.triotest.com.au/brands/siglent/digital-oscilloscopes/sds1000dl-series)

Quote
or a DS1052E for $A429.00 plus GST. at EMONA

Even a Digitech/El Crappo from Jaycar is $A549.00 GST included.
They do have a 25MHz toy for a more affordable $A239.20 GST incl.

On ebay there are some Hantek, Owon, & FNIRSI things at around $A300.00, but I'm dubious about them.
Rigols & Siglents are not much different than buying locally.

Even ancient TDS210s & 220s are around $A300.00 & upwards.
And Dave fucks a perfectly good one taking it on a mud run instead of offering it so some needy and destitute pensioner.  :P

Quote
I guess I will have to fix my Tek 7613!
Just hope you don't need a working scope to do that !
Title: Re: True analog scopes
Post by: Mechatrommer on December 13, 2022, 10:34:13 am
Well, there's zero quantization noise, so I was wandering if some applications find that important?
oo weally? can you differentiate white noise vs black noise? analog vs digital noise? english noise vs asia noise? have you heard about sinc(x)?

https://www.tek.com/en/support/faqs/why-does-my-digital-oscilloscope-have-more-noise-then-my-analog-oscilloscope (https://www.tek.com/en/support/faqs/why-does-my-digital-oscilloscope-have-more-noise-then-my-analog-oscilloscope)

https://www.youtube.com/watch?v=Znwp0pK8Tzk (https://www.youtube.com/watch?v=Znwp0pK8Tzk)
Title: Re: True analog scopes
Post by: tautech on December 13, 2022, 10:36:41 am
Quietly hoping MED digs out all the pics of his old Teks from the TEA thread and posts them here.  :popcorn:
Title: Re: True analog scopes
Post by: Mechatrommer on December 13, 2022, 11:02:50 am
please dont!
Title: Re: True analog scopes
Post by: tggzzz on December 13, 2022, 11:19:48 am
There's 12 bit DSO's available too.
Guess which kicks arse.  ;)

There are 14bit DSOs available too, but not from your supplier.

One also includes a spectrum analyser (where the extra resolution is visible), network analyser, impedance analyser, bode plots, AWG, pattern generator, logic analyser, protocol analyser, curve tracer. Plus you can create extra instruments via scripting.

Is it general purpose? Yes in some ways, no in others. Specify the job and use cases, then choose the tool.
Title: Re: True analog scopes
Post by: Sherlock Holmes on December 13, 2022, 12:13:56 pm
Well, there's zero quantization noise, so I was wandering if some applications find that important?
oo weally? can you differentiate white noise vs black noise? analog vs digital noise? english noise vs asia noise? have you heard about sinc(x)?

https://www.tek.com/en/support/faqs/why-does-my-digital-oscilloscope-have-more-noise-then-my-analog-oscilloscope (https://www.tek.com/en/support/faqs/why-does-my-digital-oscilloscope-have-more-noise-then-my-analog-oscilloscope)

https://www.youtube.com/watch?v=Znwp0pK8Tzk (https://www.youtube.com/watch?v=Znwp0pK8Tzk)

Yes, really. Didn't you know? if you convert an analog voltage to a digital representation of that voltage, you'll introduce quantization noise. If you actually watch that video, you'll see he's not talking about quantization noise.
Title: Re: True analog scopes
Post by: JPortici on December 13, 2022, 12:29:42 pm
Well, there's zero quantization noise, so I was wandering if some applications find that important?

Such as? Because I can't think of any

Yes, really. Didn't you know? if you convert an analog voltage to a digital representation of that voltage, you'll introduce quantization noise.

but for most (all?) practical purpose it doesn't matter (that's what he meant with "can you differentiate"), storage is much more valuable than the quantization noise that's introduced with sampling/converting.
I read once a paper from tek that given the size of the CRT and the linearity of the circuit, sampling at 8bit was sufficient to mimick an analog scope. Signal is too low in amplitude? That's what amplifiers are for
Title: Re: True analog scopes
Post by: tggzzz on December 13, 2022, 12:43:05 pm
Well, there's zero quantization noise, so I was wandering if some applications find that important?

Such as? Because I can't think of any

Measuring wideband white noise, and hence signal-to-noise. Easy and fast on an analogue scope, tricky on a digitising scope (display technology, quantisation).

Quote
Yes, really. Didn't you know? if you convert an analog voltage to a digital representation of that voltage, you'll introduce quantization noise.

but for most (all?) practical purpose it doesn't matter (that's what he meant with "can you differentiate"), storage is much more valuable than the quantization noise that's introduced with sampling/converting.
I read once a paper from tek that given the size of the CRT and the linearity of the circuit, sampling at 8bit was sufficient to mimick an analog scope. Signal is too low in amplitude? That's what amplifiers are for

Spectrum analysis and allied measurements are a good counter-example.

Amplifiers have their own "infelicities", e.g. frequency response, noise and headroom.
Title: Re: True analog scopes
Post by: JPortici on December 13, 2022, 01:03:39 pm
Measuring wideband white noise, and hence signal-to-noise. Easy and fast on an analogue scope, tricky on a digitising scope (display technology, quantisation).

True, i had actually that in mind as an option

Quote
Spectrum analysis and allied measurements are a good counter-example.
but we're talking about scopes here :) correct me if i'm wrong, but in the frequency domain we use intruments that downconvert a portion of the spectrum so it can be acquired with low samplerate / high resolution converters (unless the bandwidth of interest is low enough that direct sampling can be used such as in audio analyzers) so in theory the quantization noise can be lowered enough to be lower than the noise

Quote
Amplifiers have their own "infelicities", e.g. frequency response, noise and headroom.
agreed
Title: Re: True analog scopes
Post by: Sherlock Holmes on December 13, 2022, 01:10:17 pm
Well, there's zero quantization noise, so I was wandering if some applications find that important?

Such as? Because I can't think of any

Well that's the same question I'm asking, I don't know, that's why I asked!


Yes, really. Didn't you know? if you convert an analog voltage to a digital representation of that voltage, you'll introduce quantization noise.

but for most (all?) practical purpose it doesn't matter (that's what he meant with "can you differentiate"), storage is much more valuable than the quantization noise that's introduced with sampling/converting.
I read once a paper from tek that given the size of the CRT and the linearity of the circuit, sampling at 8bit was sufficient to mimick an analog scope. Signal is too low in amplitude? That's what amplifiers are for

Well in audio we routinely see 16 bits because of quantization noise, why do you think we see 12bit DSOs as well as 8bit? its to increase dynamic range, increase the vertical resolution.
Title: Re: True analog scopes
Post by: JPortici on December 13, 2022, 01:28:53 pm
Read between the lines! That comparison was between digital scopes and analog scopes, those things with thick traces and 10x8cm CRTs. Compared to those 8bit resolution is adequate.
Todays digital scopes use 8-12" screen with full HD resolution, even more if they connect directly to your PC, there is already a benefit in higher resolution converters when you display the waveform, let alone when you zoom in into a previous acquisition, and when you perform analysis on the data.. all thing you can't do with an analog scope anyway.

The point being that quantization noise while it's present, it's irrelevant if it's something you can't do with an analog scope anyway
Title: Re: True analog scopes
Post by: 2N3055 on December 13, 2022, 01:30:37 pm


1st: on CRT scope you can only see what you see on a screen with your eyes. Noise that is too small to see cannot be seen..
2nd: noise is noise. Digital, analog, periodic, stochastic.  It is garbage added to our signal in process of measurement.
3rd: if noise is smaller than what you can resolve on screen it doesn't exist for that particular purpose.
4th: no, you cannot see to more than 8-9 bit of resolution on analog scope. It doesn't have perfect focus, and screen is too small
5th: no you cannot see 16bit quantization noise while looking at screen with full range signal on it (as analogous to CRT scope). You don't have screen with 65536 pixels vertically. 12 bit is 4096 pixels vertically.
Only reason you can "see" quantization effects is that you have digitized data in numeric format where you can easily look at 5th decimal and say "look there is a step". 
Make an experiment: create 8, 10, 12 and 16bit sinewave as an array (in any software) and then plot them on screen.
You will see what I mean.
Title: Re: True analog scopes
Post by: precaud on December 13, 2022, 01:31:30 pm
Besides familiarity and ease of use, there are two main reasons why I still keep a Tek analog scope on the bench:
7CT1N curve tracer plugin
7A22 diff amp

I'm still waiting for a DSO maker to offer anything remotely as useful as these two plugins.
Title: Re: True analog scopes
Post by: Mechatrommer on December 13, 2022, 01:50:03 pm
Yes, really. Didn't you know? if you convert an analog voltage to a digital representation of that voltage, you'll introduce quantization noise. If you actually watch that video, you'll see he's not talking about quantization noise.
agree it is there, but i mean on which part quantization noise is visible there on the screen? or when it matters?
Title: Re: True analog scopes
Post by: Sherlock Holmes on December 13, 2022, 01:53:00 pm
Well, there's zero quantization noise, so I was wandering if some applications find that important?
oo weally? can you differentiate white noise vs black noise? analog vs digital noise? english noise vs asia noise? have you heard about sinc(x)?

https://www.tek.com/en/support/faqs/why-does-my-digital-oscilloscope-have-more-noise-then-my-analog-oscilloscope (https://www.tek.com/en/support/faqs/why-does-my-digital-oscilloscope-have-more-noise-then-my-analog-oscilloscope)

https://www.youtube.com/watch?v=Znwp0pK8Tzk (https://www.youtube.com/watch?v=Znwp0pK8Tzk)

Yes, really. Didn't you know? if you convert an analog voltage to a digital representation of that voltage, you'll introduce quantization noise. If you actually watch that video, you'll see he's not talking about quantization noise.

agree it is there, but i mean on which part quantization noise is visible there on the screen? or when it matters?

That's the question I'm asking! That's what the OP is asking, when/why/if would an analog scope ever be preferable to a digital one, try answering rather than asking me my own question!
Title: Re: True analog scopes
Post by: tggzzz on December 13, 2022, 02:07:50 pm
Spectrum analysis and allied measurements are a good counter-example.
but we're talking about scopes here :) correct me if i'm wrong, but in the frequency domain we use intruments that downconvert a portion of the spectrum so it can be acquired with low samplerate / high resolution converters (unless the bandwidth of interest is low enough that direct sampling can be used such as in audio analyzers) so in theory the quantization noise can be lowered enough to be lower than the noise

That's one type of spectrum analyser; there are others. One keyphrase used by HPAK is "dynamic signal analyser", e.g. https://www.keysight.com/us/en/product/35670A/fft-dynamic-signal-analyzer-dc1024-khz.html (https://www.keysight.com/us/en/product/35670A/fft-dynamic-signal-analyzer-dc1024-khz.html)

Many scopes now have an option to post-process captured samples using an FFT. Limitations (compared with "RF" SAs) are linearity and quantisation leading to spurious spurs.
Title: Re: True analog scopes
Post by: Mechatrommer on December 13, 2022, 02:20:14 pm
Well in audio we routinely see 16 bits because of quantization noise, why do you think we see 12bit DSOs as well as 8bit? its to increase dynamic range, increase the vertical resolution.
dynamic range is different, noise floor is different.

Well, there's zero quantization noise, so I was wandering if some applications find that important?
oo weally? can you differentiate white noise vs black noise? analog vs digital noise? english noise vs asia noise? have you heard about sinc(x)?
Yes, really. Didn't you know? if you convert an analog voltage to a digital representation of that voltage, you'll introduce quantization noise. If you actually watch that video, you'll see he's not talking about quantization noise.
agree it is there, but i mean on which part quantization noise is visible there on the screen? or when it matters?

That's the question I'm asking! That's what the OP is asking, when/why/if would an analog scope ever be preferable to a digital one, try answering rather than asking me my own question!
sorry that was look like a claim that analog scope has zero quantization noise. but since digital scope's quantization noise is also invisible (as you've implicitly agree) so basically not much different application between both, other than soothing phosphor glow, or if you want to miss modern digital features such as storage recording, digital encoding, SW FFT, bode plot etc.. someone will tell we can bode plot in analog scope, agreed, just not on top east made analog scope..

Well, there's zero quantization noise, so I was wandering if some applications find that important?
Such as? Because I can't think of any
Measuring wideband white noise, and hence signal-to-noise. Easy and fast on an analogue scope, tricky on a digitising scope (display technology, quantisation).
if the analog scope minimum sensitivity is 1mV/div, then not much different with budget digital scope, furthermore, noise is noise and shown in digital scope, using markers and lines should do the trick directly, not so much i think with analog that you need to increase phosphor intensity to see more hidden noise and guestimating from the glow thickness by eyes. if you meant 500uv/div and lower sensitivity analog scope, then top east brand dont have it, its only available in used tek high end analog scope market.
Title: Re: True analog scopes
Post by: Mechatrommer on December 13, 2022, 02:22:00 pm
Spectrum analysis and allied measurements are a good counter-example.
but we're talking about scopes here :) correct me if i'm wrong, but in the frequency domain we use intruments that downconvert a portion of the spectrum so it can be acquired with low samplerate / high resolution converters (unless the bandwidth of interest is low enough that direct sampling can be used such as in audio analyzers) so in theory the quantization noise can be lowered enough to be lower than the noise

That's one type of spectrum analyser; there are others. One keyphrase used by HPAK is "dynamic signal analyser", e.g. https://www.keysight.com/us/en/product/35670A/fft-dynamic-signal-analyzer-dc1024-khz.html (https://www.keysight.com/us/en/product/35670A/fft-dynamic-signal-analyzer-dc1024-khz.html)

Many scopes now have an option to post-process captured samples using an FFT. Limitations (compared with "RF" SAs) are linearity and quantisation leading to spurious spurs.
please not the "FSA/DSA/analog" all = sampling scope again! SA has -200dB noise floor, you cant see that on any analog nor digital scope.
Title: Re: True analog scopes
Post by: vk6zgo on December 13, 2022, 02:39:09 pm
For a brief, shining moment, when the $A was above parity with the $US, a new DSO was affordable for those of us on a restricted budget, but these days, we are confronted with things like a SDS-1102DL+ for $A598.00 plus GST.

https://www.wavecom.com.au/product_view.php?id_product=1035&gclid=CjwKCAiAv9ucBhBXEiwA6N8nYE8M2VLDpCwIWvijQbOtvdgxNkJWnPk-W3c (https://www.wavecom.com.au/product_view.php?id_product=1035&gclid=CjwKCAiAv9ucBhBXEiwA6N8nYE8M2VLDpCwIWvijQbOtvdgxNkJWnPk-W3c)
Wow, Wavecom are really taking the piss !  :P
$100 + GST cheaper for the same 100 MHz 2ch model at the Oz master importers Trio:
https://www.triotest.com.au/brands/siglent/digital-oscilloscopes/sds1000dl-series (https://www.triotest.com.au/brands/siglent/digital-oscilloscopes/sds1000dl-series)

Quote
or a DS1052E for $A429.00 plus GST. at EMONA

Even a Digitech/El Crappo from Jaycar is $A549.00 GST included.
They do have a 25MHz toy for a more affordable $A239.20 GST incl.

On ebay there are some Hantek, Owon, & FNIRSI things at around $A300.00, but I'm dubious about them.
Rigols & Siglents are not much different than buying locally.

Even ancient TDS210s & 220s are around $A300.00 & upwards.
And Dave fucks a perfectly good one taking it on a mud run instead of offering it so some needy and destitute pensioner.  :P

Quote
I guess I will have to fix my Tek 7613!
Just hope you don't need a working scope to do that !

The (PSU) fault, luckily (in one way) doesn't need a decent 'scope to fix it---the little 10MHz Analog Digitech would do----it's just getting the motivation to do it.
The biggest problem is that everything else is jostling for position on the queue, & my "get up & go" has got up & went! ;D
Title: Re: True analog scopes
Post by: Sherlock Holmes on December 13, 2022, 02:56:52 pm
Well in audio we routinely see 16 bits because of quantization noise, why do you think we see 12bit DSOs as well as 8bit? its to increase dynamic range, increase the vertical resolution.
dynamic range is different, noise floor is different.

Well, there's zero quantization noise, so I was wandering if some applications find that important?
oo weally? can you differentiate white noise vs black noise? analog vs digital noise? english noise vs asia noise? have you heard about sinc(x)?
Yes, really. Didn't you know? if you convert an analog voltage to a digital representation of that voltage, you'll introduce quantization noise. If you actually watch that video, you'll see he's not talking about quantization noise.
agree it is there, but i mean on which part quantization noise is visible there on the screen? or when it matters?

That's the question I'm asking! That's what the OP is asking, when/why/if would an analog scope ever be preferable to a digital one, try answering rather than asking me my own question!
sorry that was look like a claim that analog scope has zero quantization noise. but since digital scope's quantization noise is also invisible (as you've implicitly agree) so basically not much different application between both, other than soothing phosphor glow, or if you want to miss modern digital features such as storage recording, digital encoding, SW FFT, bode plot etc.. someone will tell we can bode plot in analog scope, agreed, just not on top east made analog scope..

Well, there's zero quantization noise, so I was wandering if some applications find that important?
Such as? Because I can't think of any
Measuring wideband white noise, and hence signal-to-noise. Easy and fast on an analogue scope, tricky on a digitising scope (display technology, quantisation).
if the analog scope minimum sensitivity is 1mV/div, then not much different with budget digital scope, furthermore, noise is noise and shown in digital scope, using markers and lines should do the trick directly, not so much i think with analog that you need to increase phosphor intensity to see more hidden noise and guestimating from the glow thickness by eyes. if you meant 500uv/div and lower sensitivity analog scope, then top east brand dont have it, its only available in used tek high end analog scope market.

Well yes, an analog scope as you know, cannot have quantization noise. But my scope has an 8 bit vertical resolution, that's 256 resolution yet the display has a vertical pixel resolution of 480. There are quantization effects that are undoubtedly present, my question was to anyone, especially professional engineers, whether there are ever cases, domains, situations where an analog scope (perhaps one of the more recent analog high end scopes) is advantageous.

There may well be no such situations at all, ever, but I don't know so wanted to see if any experts here could point out examples.
Title: Re: True analog scopes
Post by: mag_therm on December 13, 2022, 03:01:51 pm
Before I retired I used to travel to sites in some countries  to assist the local agent or sub- company with problems.
The typical anecdote was the the DSO scope would be unpacked, the tech would start pecking away at the menu screens and it would be morning coffee time before scope was displaying a usable trace.
Saying "Now , let us look at the dv/dt on THAT edge af THAT Channel" would elicit another pecking session.

I recently got a basic DSO to help the aged 466 ASO on the hobby bench.
But most of the time I still switch on the 466.

I use single shot a lot on the inverters.
Unfortunately, the DSO GWI1202B has a "Default" button right under the "Single Shot" and next to the timebase knob!
Bumping that default button is a mild disaster, needing another pecking session.
Title: Re: True analog scopes
Post by: Mechatrommer on December 13, 2022, 03:08:02 pm
Bumping that default button is a mild disaster, needing another pecking session.
if it only give bad things to you, just peel the rubber button off so there is no more disaster..
Title: Re: True analog scopes
Post by: mag_therm on December 13, 2022, 03:15:01 pm
Just tried, thanks. It did not come off with some force, so I'm scared of breaking it.
Scope is still in warranty, Maybe I will wait until warranty is over.
I had though of making a little flap or milling aluminum surround guard to glue on but there is very little space around the button
Title: Re: True analog scopes
Post by: mawyatt on December 13, 2022, 03:36:34 pm
We've been using "analog" scopes for well over 60 years, got our 1st analog scope (Heathkit) when 12, and utilized just about every Tektronix analog scope ever made. Even did custom plug-ins if any folks remember those from Tek, they were the metal case plug-in and blank front panel with a prototype PCB inside and interface connector. Had many "custom plug-in functions" for the various Mainframe Type Tek analog scopes we utilized.

From an old (very old) analog diehard it took some time to "pull the trigger" on a modern DSO for ourself, having the old "analog" bias prevented this for awhile!!

Now after some time using such, comparing an analog scope to a modern low noise, high resolution DSO is like comparing a Simpson 260 to a Keysight 34465A or Keithley DMM6500. We keep a couple Tek 2465s around just to remind us of how good these newer DSO are, and to play around with just as reminders of days of old ::)

Best,
Title: Re: True analog scopes
Post by: 2N3055 on December 13, 2022, 03:48:30 pm

Well yes, an analog scope as you know, cannot have quantization noise. But my scope has an 8 bit vertical resolution, that's 256 resolution yet the display has a vertical pixel resolution of 480. There are quantization effects that are undoubtedly present, my question was to anyone, especially professional engineers, whether there are ever cases, domains, situations where an analog scope (perhaps one of the more recent analog high end scopes) is advantageous.

There may well be no such situations at all, ever, but I don't know so wanted to see if any experts here could point out examples.

And what do you thing CRT scope has no noise? How thick is the trace? There is a limit on "analog resolution", it is called noise floor.
It is same as "megapixel wars" in SLR cameras, where saying "film is analog" doesn't mean it has unlimited resolution. It doesn't, it has grain. And "analog resolution" (sharpness) of lenses is also a thing...

Decent DSO of today will have less noise (despite 8 bits) than most CRT scopes with exception of few special ones.
And higher bit (10bit and up) will have more detail than any analog CRT scope.
And FFT, math, measurements, analysis, mask test, single shot capture, decodes... And huge screens in comparisons. Networking, remote control, easy saving of data and screenshots...

There is only one thing where CRT is still better : X-Y mode for scope art.. And as someone here mentioned, some of the fancy CRT modular scopes had some special modules that have no equivalent, but that is not a analog/digital difference.
Those a niche enough there is no imperative for manufacturers to invest into developing that anmore. If there was need for it, it would be made.
Title: Re: True analog scopes
Post by: Sherlock Holmes on December 13, 2022, 04:15:51 pm

Well yes, an analog scope as you know, cannot have quantization noise. But my scope has an 8 bit vertical resolution, that's 256 resolution yet the display has a vertical pixel resolution of 480. There are quantization effects that are undoubtedly present, my question was to anyone, especially professional engineers, whether there are ever cases, domains, situations where an analog scope (perhaps one of the more recent analog high end scopes) is advantageous.

There may well be no such situations at all, ever, but I don't know so wanted to see if any experts here could point out examples.

And what do you thing CRT scope has no noise? How thick is the trace? There is a limit on "analog resolution", it is called noise floor.
It is same as "megapixel wars" in SLR cameras, where saying "film is analog" doesn't mean it has unlimited resolution. It doesn't, it has grain. And "analog resolution" (sharpness) of lenses is also a thing...

Decent DSO of today will have less noise (despite 8 bits) than most CRT scopes with exception of few special ones.
And higher bit (10bit and up) will have more detail than any analog CRT scope.
And FFT, math, measurements, analysis, mask test, single shot capture, decodes... And huge screens in comparisons. Networking, remote control, easy saving of data and screenshots...

There is only one thing where CRT is still better : X-Y mode for scope art.. And as someone here mentioned, some of the fancy CRT modular scopes had some special modules that have no equivalent, but that is not a analog/digital difference.
Those a niche enough there is no imperative for manufacturers to invest into developing that anmore. If there was need for it, it would be made.

I don't disagree, my OP was intended to find out if there were any specialized industries or situations in which an analog scope was preferred. For example, what was the highest ever bandwidth CRT scope? was it a higher frequency than the highest bandwidth DSO today?





Title: Re: True analog scopes
Post by: tggzzz on December 13, 2022, 04:16:49 pm
There is only one thing where CRT is still better : X-Y mode for scope art..

Here's another: where a scope (analogue or digitising) with analogue sampling head is still the best: dealing with overload.

If you want to observe the full-scale transient settling time of an op-amp's or DAC's output to 0.1%, then an analogue sampling head is still required.

Any front-end analogue circuit will be overloaded and have "unhelpful" recovery from overload characteristics. In contrast, the analogue sampling head simply ignores any input (including overload) until the sampling instant. If I could get the thermal paper, I'd be able show a photograph of a chart recorder displaying 150ps risetimes :)

Of course, given an analogue sampling head, a pen chart recorder is sufficient for plotting the transient. No need for this fancy high speed display rubbish overkill.

I refer readers to the aphorism in my .sig.
Title: Re: True analog scopes
Post by: TimFox on December 13, 2022, 05:11:43 pm
As a practical matter in this modern age, there are no analog oscilloscopes in production that are as good as, say, a Tektronix 7904 or 2465.
I still use a 7603, but to operate a good Tektronix analog scope means having the dedication to maintain it yourself, just like owning a Saab.
Title: Re: True analog scopes
Post by: 2N3055 on December 13, 2022, 05:52:29 pm
There is only one thing where CRT is still better : X-Y mode for scope art..

Here's another: where a scope (analogue or digitising) with analogue sampling head is still the best: dealing with overload.

If you want to observe the full-scale transient settling time of an op-amp's or DAC's output to 0.1%, then an analogue sampling head is still required.

Any front-end analogue circuit will be overloaded and have "unhelpful" recovery from overload characteristics. In contrast, the analogue sampling head simply ignores any input (including overload) until the sampling instant. If I could get the thermal paper, I'd be able show a photograph of a chart recorder displaying 150ps risetimes :)

Of course, given an analogue sampling head, a pen chart recorder is sufficient for plotting the transient. No need for this fancy high speed display rubbish overkill.

I refer readers to the aphorism in my .sig.

What you say is absolutely correct. But.....

OP doesn't (and neither we are) talking about these types of scopes. They are very limited in usability and quite special.
These are not what people call analog CRT scopes. Such is popular lingo, sorry. Same as when people say digital sampling scope they mean Realtime DSO. Most never saw or used analog sampling scope and have no interest in it.

He specifically wants a comparison between classic analog CRT (direct writing of CRT with analog X/Y beam deflection) and modern real time DSO as a replacement.

We better not venture where more confusion will be brought in the picture..
Title: Re: True analog scopes
Post by: tautech on December 13, 2022, 07:33:03 pm
Besides familiarity and ease of use, there are two main reasons why I still keep a Tek analog scope on the bench:
7CT1N curve tracer plugin
7A22 diff amp

I'm still waiting for a DSO maker to offer anything remotely as useful as these two plugins.
It might not be long before Curve Tracers become another DSO feature but in the meantime while you're nursing that old gear along (no disrespect implied) you might like to look at what some have done in their spare time and follow a few links to observe where it led them:
https://www.eevblog.com/forum/testgear/fooln-around-with-dso-awg/ (https://www.eevblog.com/forum/testgear/fooln-around-with-dso-awg/)

What's so special about the diff amp plugin that differential probes can't do ?  :-//
I'd really like to know.
Title: Re: True analog scopes
Post by: tautech on December 13, 2022, 07:37:00 pm
I guess I will have to fix my Tek 7613!
Just hope you don't need a working scope to do that !
The (PSU) fault, luckily (in one way) doesn't need a decent 'scope to fix it---the little 10MHz Analog Digitech would do----it's just getting the motivation to do it.
The biggest problem is that everything else is jostling for position on the queue, & my "get up & go" has got up & went! ;D
:-DD Man do I know that problem too !
Shame we weren't visiting the lad this year as I'd happily bring some tools and help you fix it. Got aircon for them darn hot days you get this time of year ?
Title: Re: True analog scopes
Post by: Mechatrommer on December 13, 2022, 07:45:35 pm
He specifically wants a comparison between classic analog CRT (direct writing of CRT with analog X/Y beam deflection) and modern real time DSO as a replacement.
no. from later explanations, what he want to hear is justifiable excuse why analog is still applicable today. he doesnt care if digital is better, he only want to know why analog is better! so maybe he can scour some tek analog scope with sampling head that are still in ebay while they are still there... btw x-y art is just for kids who have nothing better to do imho, no offense... https://hackaday.com/tag/oscilloscope-art/ (https://hackaday.com/tag/oscilloscope-art/)

https://www.youtube.com/watch?v=3JkftTzBc90 (https://www.youtube.com/watch?v=3JkftTzBc90)
Title: Re: True analog scopes
Post by: 2N3055 on December 13, 2022, 08:56:18 pm
He specifically wants a comparison between classic analog CRT (direct writing of CRT with analog X/Y beam deflection) and modern real time DSO as a replacement.
no. from later explanations, what he want to hear is justifiable excuse why analog is still applicable today. he doesnt care if digital is better, he only want to know why analog is better! so maybe he can scour some tek analog scope with sampling head that are still in ebay while they are still there... btw x-y art is just for kids who have nothing better to do imho, no offense... https://hackaday.com/tag/oscilloscope-art/ (https://hackaday.com/tag/oscilloscope-art/)


I said truth, only thing CRT scope does better is X-Y, but difference is only visible with scope art. I have no use for scope art, but i don't judge.
If someone likes it, good for them.
Title: Re: True analog scopes
Post by: TimFox on December 13, 2022, 09:48:17 pm
He specifically wants a comparison between classic analog CRT (direct writing of CRT with analog X/Y beam deflection) and modern real time DSO as a replacement.
no. from later explanations, what he want to hear is justifiable excuse why analog is still applicable today. he doesnt care if digital is better, he only want to know why analog is better! so maybe he can scour some tek analog scope with sampling head that are still in ebay while they are still there... btw x-y art is just for kids who have nothing better to do imho, no offense... https://hackaday.com/tag/oscilloscope-art/ (https://hackaday.com/tag/oscilloscope-art/)


I said truth, only thing CRT scope does better is X-Y, but difference is only visible with scope art. I have no use for scope art, but i don't judge.
If someone likes it, good for them.

X-Y is also good for curve tracing of non-linear devices.
Occasionally, one might need a Lissajous figure display for other than Christmas decoration.
Title: Re: True analog scopes
Post by: Gyro on December 13, 2022, 10:01:16 pm
It might not be long before Curve Tracers become another DSO feature...

I think I saw one of those... Oh wait, they put a $20 LCR ESR Transistor checker in the same box  ;D

https://www.amazon.co.uk/Portable-Handheld-Oscilloscope-Bandwidth-Transistor/dp/B0B5MZRS35/ref=sr_1_5?keywords=oscilloscope&qid=1670968436&sr=8-5 (https://www.amazon.co.uk/Portable-Handheld-Oscilloscope-Bandwidth-Transistor/dp/B0B5MZRS35/ref=sr_1_5?keywords=oscilloscope&qid=1670968436&sr=8-5)

Title: Re: True analog scopes
Post by: 2N3055 on December 13, 2022, 10:17:21 pm
He specifically wants a comparison between classic analog CRT (direct writing of CRT with analog X/Y beam deflection) and modern real time DSO as a replacement.
no. from later explanations, what he want to hear is justifiable excuse why analog is still applicable today. he doesnt care if digital is better, he only want to know why analog is better! so maybe he can scour some tek analog scope with sampling head that are still in ebay while they are still there... btw x-y art is just for kids who have nothing better to do imho, no offense... https://hackaday.com/tag/oscilloscope-art/ (https://hackaday.com/tag/oscilloscope-art/)


I said truth, only thing CRT scope does better is X-Y, but difference is only visible with scope art. I have no use for scope art, but i don't judge.
If someone likes it, good for them.

X-Y is also good for curve tracing of non-linear devices.
Occasionally, one might need a Lissajous figure display for other than Christmas decoration.

All of my scopes will do that just fine... It's really fast dynamic updates (like analog video on CRT scope) that you cannot do or only partially....

Title: Re: True analog scopes
Post by: TimFox on December 13, 2022, 10:27:47 pm
Will your DSOs update fast enough to adjust one oscillator to syntonize with another?
Title: Re: True analog scopes
Post by: tautech on December 13, 2022, 10:49:11 pm
Will your DSOs update fast enough to adjust one oscillator to syntonize with another?
Hell yeah, that's really basic stuff.

Try it easily with a DSO and a 2ch AWG and watch the frequencies sync as you tune them to equivalent frequencies.
Even old DSO's could do that too before manufacturers started optimizing XY mode.
Title: Re: True analog scopes
Post by: 2N3055 on December 13, 2022, 11:25:21 pm
Will your DSOs update fast enough to adjust one oscillator to syntonize with another?

You can do Lissajous figures just nicely... And when you are synchronizing two frequencies, it gets slower as you come close.
 
Title: Re: True analog scopes
Post by: vk6zgo on December 14, 2022, 12:01:17 am
He specifically wants a comparison between classic analog CRT (direct writing of CRT with analog X/Y beam deflection) and modern real time DSO as a replacement.
no. from later explanations, what he want to hear is justifiable excuse why analog is still applicable today. he doesnt care if digital is better, he only want to know why analog is better! so maybe he can scour some tek analog scope with sampling head that are still in ebay while they are still there... btw x-y art is just for kids who have nothing better to do imho, no offense... https://hackaday.com/tag/oscilloscope-art/ (https://hackaday.com/tag/oscilloscope-art/)


I said truth, only thing CRT scope does better is X-Y, but difference is only visible with scope art. I have no use for scope art, but i don't judge.
If someone likes it, good for them.

X-Y is also good for curve tracing of non-linear devices.
Occasionally, one might need a Lissajous figure display for other than Christmas decoration.

All of my scopes will do that just fine... It's really fast dynamic updates (like analog video on CRT scope) that you cannot do or only partially....

The very early DSOs put off a lot of people who were initially "digital friendly".
When Tektronix & HP went down the DSO "rabbit hole", their reps would roll up to TV Stations to demonstrate the "latest & greatest" DSO.
After they showed us all the "bells & whistles", someone would inevitably say: -

"OK, let's look at some video signals."

The very first generation couldn't even display line rate signals properly, as their sample rate dropped so radically that the higher frequency video components were lost, with the colour burst looking like something you would scribble on a blackboard, rather than the sharp, clear, "RF" envelope.

Field rate?---- Forget it!
The sample rate was so low, that the display looked like my overgrown back yard!

Each generation got ever so slightly better, until the last one I was involved with was actually "sorta" usable, although its sample rate was still low enough to lose the highest frequency BW components & produce an annoying "beat note" with the colour signal.

Later, we had a THS720 (for a special job, because of its insulated inputs), & I used it a few times for fixing Picture Monitors.
It was OK, but not spectacularly good.

One thing I expected with those early DSOs, was to be able to store a "good" waveform & overlay it with the "suspect" waveform from a DUT.
This would have been a "God send" for fault finding, but was probably too costly in memory in those early days.

The Analog video failing seemed to bedevil DSOs for many years, especially the cheap ones, as witness many horrific displays of video waveforms appearing on the Internet.

My understanding was that modern DSOs no longer had any problems, but I don't have a modern, or indeed, any DSO.

One thing that freaks me out with some modern DSOs, is that screenshots from them show a lot of extraneous, distracting information in glaring primary colours.(This is probably a user problem, as I've particularly noticed this where people are looking for suggestions about a problem).
The old ones were much more soothing to my aged eyes!

Title: Re: True analog scopes
Post by: bdunham7 on December 14, 2022, 12:35:17 am
XY works fine on many modern DSOs, although it takes a few extra steps to set up properly.

https://youtu.be/9eF5UcLgOpg

What they typically can't do is XYZ (with a few exceptions apparently that I haven't seen) or the Kikusui 'three ring circus'.

https://youtu.be/QUPK-7K6YbY
Title: Re: True analog scopes
Post by: tautech on December 14, 2022, 12:51:16 am
vk6zgo
Here's what a $500 DSO can do these days but not without some trigger Holdoff to prevent retriggering and then I cocked up using the falling edge trigger from a previous decoding demo to a customer.  :palm:

(https://www.eevblog.com/forum/testgear/true-analog-scopes/?action=dlattach;attach=1663540)

We could also use a Pulse or some period trigger to get more precise results but that should give you an idea.

Now we have affordable scopes with zone triggers a new world opens and with the base model in this range now just $1k until years end offers so much more as plain standard capability without requiring purchase of some $ option.  :horse:

First is much the same as the cheaper 4ch X-E and this time with a rising trigger.  ::)

(https://www.eevblog.com/forum/testgear/true-analog-scopes/?action=dlattach;attach=1663546)

Or we can punch a STOP to check what's really there:

(https://www.eevblog.com/forum/testgear/true-analog-scopes/?action=dlattach;attach=1663552)

Our we can go all out and use one of the Zone triggers with a Not Intersect setting

(https://www.eevblog.com/forum/testgear/true-analog-scopes/?action=dlattach;attach=1663558)
Title: Re: True analog scopes
Post by: tggzzz on December 14, 2022, 08:41:08 am
The Analog video failing seemed to bedevil DSOs for many years, especially the cheap ones, as witness many horrific displays of video waveforms appearing on the Internet.
(many sensible points snipped)

Not being able to display a video signal was an easily defined and understood example of a general problem. Readers could easily extrapolate that example to see how it could cause problems with the waveforms they needed to observe.

Curiously one early (1980) Tek got it right: the Tek 468. It has a 10MHz useful digitising bandwidth, and can display "modulation" or "mean" waveforms. The "modulation" setting is called "peak detect" nowadays.

Later Tek scopes couldn't, since they used a CCD to sample the waveform for subsequent digitisation.

(https://w140.com/tekwiki/images/thumb/b/b2/468-am.jpg/800px-468-am.jpg)
Title: Re: True analog scopes
Post by: james_s on December 14, 2022, 09:04:57 am
I'm skeptical that anyone is actually producing new analog scopes anymore. I could see there being a few thousand of them stacked in a warehouse somewhere that are being sold to the small handful of customers still buying one but there can't possibly be enough demand for mass production.
Title: Re: True analog scopes
Post by: james_s on December 14, 2022, 09:06:50 am
I said truth, only thing CRT scope does better is X-Y, but difference is only visible with scope art. I have no use for scope art, but i don't judge.
If someone likes it, good for them.

I use my analog scope when working on vector arcade game boards. No DSO that I've tried could even display a recognizable image.
Title: Re: True analog scopes
Post by: tautech on December 14, 2022, 09:19:23 am
I said truth, only thing CRT scope does better is X-Y, but difference is only visible with scope art. I have no use for scope art, but i don't judge.
If someone likes it, good for them.

I use my analog scope when working on vector arcade game boards. No DSO that I've tried could even display a recognizable image.
Screenshot please.  :-DD
Title: Re: True analog scopes
Post by: 2N3055 on December 14, 2022, 09:44:13 am
I said truth, only thing CRT scope does better is X-Y, but difference is only visible with scope art. I have no use for scope art, but i don't judge.
If someone likes it, good for them.

I use my analog scope when working on vector arcade game boards. No DSO that I've tried could even display a recognizable image.

That is because you use it as a analog video X-Y(-Z) monitor.  Which would need 5-10Mhz video bandwidth. And is same as scope art, basically..
As I said, all of that is very niche...
Title: Re: True analog scopes
Post by: robert.rozee on December 14, 2022, 11:30:38 am
i can see a few places where a CRT/analog oscilloscope is a preferable solution:

1. where there are tight cost and resource constraints. ie, poor people who can only afford a 2nd hand CRT scope, perhaps living in a place where new equipment is not available. think of the slums in places like india.

2. in locations where radiation hardening is necessary. for instance, off-planet. there may be such situations where semiconductors can not be depended upon, and fully-valved equipment needs to be used.

3. in situations where the displayed trace is safety-critical, and a digital solution introduces the possibility of failure modes that are not acceptable. for instance, displaying the sine wave output from a generation plant, where a DSO could fail with a frozen display. basically a CRT/analog oscilloscope provides an extremely simply display where any failure within the instrument is guaranteed to remove the trace on the screen; a DSO can lock up with a 'good' image on the display even if there is a 'bad' input signal.

the above are all extreme examples, but non-the-less could still exist in the real world.

4. it is also important that  we preserve "old technology" so that if some global mishap knocks back society, we can pick up at a level of technology that is still achievable within any 'new world order' without having to go back to the stone age. for instance, if a massive solar flare knocked out all of our existing semiconductor electronics infrastructure, it would be nice for human society to be able to pick up at the level of 1920's valve technology and rebuild from there.


cheers,
rob   :-)
Title: Re: True analog scopes
Post by: JPortici on December 14, 2022, 11:51:58 am
I said truth, only thing CRT scope does better is X-Y, but difference is only visible with scope art. I have no use for scope art, but i don't judge.
If someone likes it, good for them.

I use my analog scope when working on vector arcade game boards. No DSO that I've tried could even display a recognizable image.
Screenshot please.  :-DD

I believe him, vector displays are tricky beasts and i can't name a digital scope that has the Z input (i know there are a couple but i can't remember which they are)
Title: Re: True analog scopes
Post by: Sherlock Holmes on December 14, 2022, 12:18:07 pm
i can see a few places where a CRT/analog oscilloscope is a preferable solution:

1. where there are tight cost and resource constraints. ie, poor people who can only afford a 2nd hand CRT scope, perhaps living in a place where new equipment is not available. think of the slums in places like india.

2. in locations where radiation hardening is necessary. for instance, off-planet. there may be such situations where semiconductors can not be depended upon, and fully-valved equipment needs to be used.

3. in situations where the displayed trace is safety-critical, and a digital solution introduces the possibility of failure modes that are not acceptable. for instance, displaying the sine wave output from a generation plant, where a DSO could fail with a frozen display. basically a CRT/analog oscilloscope provides an extremely simply display where any failure within the instrument is guaranteed to remove the trace on the screen; a DSO can lock up with a 'good' image on the display even if there is a 'bad' input signal.

the above are all extreme examples, but non-the-less could still exist in the real world.

4. it is also important that  we preserve "old technology" so that if some global mishap knocks back society, we can pick up at a level of technology that is still achievable within any 'new world order' without having to go back to the stone age. for instance, if a massive solar flare knocked out all of our existing semiconductor electronics infrastructure, it would be nice for human society to be able to pick up at the level of 1920's valve technology and rebuild from there.


cheers,
rob   :-)

Actually that's a  very good point, availability. The very presence of software, influences reliability. My Siglent will lock up sometimes due to bugs and must be repowered, often losing several precisely set parameters, no analog scope will, can, fall victim to that.
Title: Re: True analog scopes
Post by: xrunner on December 14, 2022, 12:22:20 pm
My Siglent will lock up sometimes due to bugs and must be repowered, often losing several precisely set parameters, no analog scope will, can, fall victim to that.

If you said so earlier I missed it, but what model Siglent are you referring to?
Title: Re: True analog scopes
Post by: Sherlock Holmes on December 14, 2022, 12:29:41 pm
My Siglent will lock up sometimes due to bugs and must be repowered, often losing several precisely set parameters, no analog scope will, can, fall victim to that.

If you said so earlier I missed it, but what model Siglent are you referring to?

Its an SDS1204X-E.
Title: Re: True analog scopes
Post by: precaud on December 14, 2022, 02:00:11 pm
What's so special about the diff amp plugin that differential probes can't do ?  :-//
I'd really like to know.

: 10uV/div sensitivity
: Selectable hi- and lo-pass filters
: Generous DC offset
Title: Re: True analog scopes
Post by: mawyatt on December 14, 2022, 03:45:10 pm
Those old Tek 7A22 Analog Diff Amp Plug-ins were certainly useful.

Seems like a good product/function to implement for modern DSO use, maybe in an external Differential Probe type  ;)

Best,
Title: Re: True analog scopes
Post by: switchabl on December 14, 2022, 03:47:35 pm
Seems like a good product/function to implement for modern DSO use, maybe in an external Differential Probe type  ;)

https://www.tek.com/en/datasheet/ada400a-differential-preamplifier-datasheet (https://www.tek.com/en/datasheet/ada400a-differential-preamplifier-datasheet)
Title: Re: True analog scopes
Post by: precaud on December 14, 2022, 04:58:47 pm
https://www.tek.com/en/datasheet/ada400a-differential-preamplifier-datasheet (https://www.tek.com/en/datasheet/ada400a-differential-preamplifier-datasheet)

Nice, but quite pricey...
Title: Re: True analog scopes
Post by: tautech on December 14, 2022, 07:23:55 pm
My Siglent will lock up sometimes due to bugs and must be repowered, often losing several precisely set parameters, no analog scope will, can, fall victim to that.

If you said so earlier I missed it, but what model Siglent are you referring to?

Its an SDS1204X-E.
FW right up to date ?
Later OS upgrade installed too ?

Hacked or genuine 200 MHz unit ? If hacked what method used ?
Have you installed any Custom Defaults ?

Last Self Cal ?

These are a quite mature product now and if running latest firmware don't give problems.

Can you list the steps/procedure to reliably make it hang ?
Title: Re: True analog scopes
Post by: tautech on December 14, 2022, 07:36:48 pm
i can see a few places where a CRT/analog oscilloscope is a preferable solution:

1. where there are tight cost and resource constraints. ie, poor people who can only afford a 2nd hand CRT scope, perhaps living in a place where new equipment is not available. think of the slums in places like india.

2. in locations where radiation hardening is necessary. for instance, off-planet. there may be such situations where semiconductors can not be depended upon, and fully-valved equipment needs to be used.

3. in situations where the displayed trace is safety-critical, and a digital solution introduces the possibility of failure modes that are not acceptable. for instance, displaying the sine wave output from a generation plant, where a DSO could fail with a frozen display. basically a CRT/analog oscilloscope provides an extremely simply display where any failure within the instrument is guaranteed to remove the trace on the screen; a DSO can lock up with a 'good' image on the display even if there is a 'bad' input signal.

the above are all extreme examples, but non-the-less could still exist in the real world.

4. it is also important that  we preserve "old technology" so that if some global mishap knocks back society, we can pick up at a level of technology that is still achievable within any 'new world order' without having to go back to the stone age. for instance, if a massive solar flare knocked out all of our existing semiconductor electronics infrastructure, it would be nice for human society to be able to pick up at the level of 1920's valve technology and rebuild from there.

cheers,
rob   :-)
Walk into any hospital and look at the ECG's in use, remember these are just a specialised oscilloscope with some counting features added and they're all modern compact LCD displays just like the modern DSO.

Here in NZ a new Asian brand mindray is taking the health industry by storm with their range of ECG's all small, light and compact. I had the pleasure to be connected to several of these new products while on a short vacation in the NZ Health system a few months back.
One of their flasier models:
https://www.mindray.com/en/products/patient-monitoring/continuous-patient-monitoring/benevision-n22-n19 (https://www.mindray.com/en/products/patient-monitoring/continuous-patient-monitoring/benevision-n22-n19)
Title: Re: True analog scopes
Post by: MarkL on December 14, 2022, 08:26:37 pm
https://www.tek.com/en/datasheet/ada400a-differential-preamplifier-datasheet (https://www.tek.com/en/datasheet/ada400a-differential-preamplifier-datasheet)

Nice, but quite pricey...
If you don't mind something a little more clunky than a boxy probe, the Tek AM502 module is similar in functionality and is more configurable. Certainly cheaper, even including the TM50x mainframe.

  https://w140.com/tekwiki/wiki/AM502 (https://w140.com/tekwiki/wiki/AM502)
Title: Re: True analog scopes
Post by: Sherlock Holmes on December 14, 2022, 08:54:29 pm
My Siglent will lock up sometimes due to bugs and must be repowered, often losing several precisely set parameters, no analog scope will, can, fall victim to that.

If you said so earlier I missed it, but what model Siglent are you referring to?

Its an SDS1204X-E.
FW right up to date ?
Later OS upgrade installed too ?

Hacked or genuine 200 MHz unit ? If hacked what method used ?
Have you installed any Custom Defaults ?

Last Self Cal ?

These are a quite mature product now and if running latest firmware don't give problems.

Can you list the steps/procedure to reliably make it hang ?

I'd need to check, it certainly isn't hacked, I bought the license for the logic analyzer update a few months ago, from Siglent US. The problem arises when using that digital mode, looking at SPI and adjusting the data display from hex/binary etc, happened several times a few months ago.
Title: Re: True analog scopes
Post by: tautech on December 14, 2022, 10:03:22 pm
My Siglent will lock up sometimes due to bugs and must be repowered, often losing several precisely set parameters, no analog scope will, can, fall victim to that.

If you said so earlier I missed it, but what model Siglent are you referring to?

Its an SDS1204X-E.
FW right up to date ?
Later OS upgrade installed too ?

Hacked or genuine 200 MHz unit ? If hacked what method used ?
Have you installed any Custom Defaults ?

Last Self Cal ?

These are a quite mature product now and if running latest firmware don't give problems.

Can you list the steps/procedure to reliably make it hang ?

I'd need to check, it certainly isn't hacked, I bought the license for the logic analyzer update a few months ago, from Siglent US. The problem arises when using that digital mode, looking at SPI and adjusting the data display from hex/binary etc, happened several times a few months ago.
You can get all the updates here:
https://int.siglent.com/download/firmwares/?ProId=12
You need to get up to 37R9 and 8.3 OS and while you're there check your SLA1016 has the latest version installed too.
Title: Re: True analog scopes
Post by: james_s on December 14, 2022, 10:50:19 pm
My thought would have been that it's defective rather than buggy. It's also possible that some data somewhere got corrupted somehow, is there a way to perform a full factory reset on it?
Title: Re: True analog scopes
Post by: tautech on December 14, 2022, 11:04:49 pm
My thought would have been that it's defective rather than buggy. It's also possible that some data somewhere got corrupted somehow, is there a way to perform a full factory reset on it?
Trouble is James, there are far to many box shufflers in this industry that send stuff out the door without even checking its firmware is latest.....Siglent NA too !
They stock their Amazon shop with unchecked products too which exposes customers to older product incarnations without the latest updates.
Many many around the world hate any device that 'phones' home to install updates but for product lines still in active development how do you get around this issue ?

We chose to check every instrument bypassing any DOA issues and updating firmware and checking and setting probes which serves as a proper check on their functionality too. Yes we find dud Siglent probes on occasion.

Resellers can take 2 paths, provide the best possible customers first experience and also know the instrument will operate as expected or be absolute experts in managing the fastest flow of stock into the marketplace.

Pick your poison.
Title: Re: True analog scopes
Post by: H713 on December 15, 2022, 06:50:55 am
I admit that my 2235 sees a whole lot less use than it used to.

That said, there are some things that the classic Tek analog scopes do better than modern digital scopes.

The biggest thing is that most modern digital scopes, in their quest to do everything under the sun, have become extremely complicated, and their UI is often a pain in the backside. It's great to be able to do really advanced things, but the really advanced stuff is 5% of my time using a scope, and if I just need to trace a sine wave through a 500 kHz bandwidth amplifier, the less I have to mess with things, the better.

Furthermore... on an analog scope, you can immediately tell exactly how it is configured without touching it. This is not the case with digital scopes, and this is a real pain - I find that I make far more bonehead measurement errors with really modern scopes than I do with those from yesteryear.

I really like my Siglent scope, and I really like the Tek scopes at work - both the TDS3054s and the new ones (I don't remember the model number) we've gotten recently. That said, I still reach for my 54622A and my Tek 2235 more often than I reach for my newer, higher-performance scopes, and this is because for a good portion of what I do, the 54622A is fast enough, and it is far less likely to annoy me than anything more recent. I actually like the TDS220 series for this reason - it's pretty usable.

Also, I'm profoundly lazy. Do you seriously think that I'm going to mess around with a software utility or a USB stick every time I want to save a scope image? Unless this is going in a formal report (or has intellectual property issues) I'm going to snap a picture with my phone. Incidentally, CRTs tend to photograph really well.

And finally, I don't have to put a brick of lead behind my analog scope to stop it from sliding across the bench when I try to connect a probe to it.


So aside from the satisfaction of using a good analog oscilloscope (the appearance of the traces on a CRT, the tactile feel of switches, etc), the main advantage they still hold has more to do with the user interface on a lot of modern scopes.
Title: Re: True analog scopes
Post by: H713 on December 15, 2022, 07:09:52 am
Oh, and I believe someone earlier in this thread asked about the fastest analog scope.

To my knowledge, the fastest analog scope was a modified version of the Tektronix 519 that achieved a 3 GHz bandwidth. That said, the 519 (in all iterations) is a very bizarre scope, and not a terribly useful one.

It was a very clever way to achieve insane bandwidths in the 1960s, but it made for a scope with a low vertical sensitivity, tiny viewing area, and a wacky 125 ohm input impedance.

I don't know if this is true, but what I was told is that Tek developed the 519 specifically for LANL and LLNL, and that they accounted for most of the 519s sold.


Title: Re: True analog scopes
Post by: tggzzz on December 15, 2022, 09:24:32 am
I admit that my 2235 sees a whole lot less use than it used to.

That said, there are some things that the classic Tek analog scopes do better than modern digital scopes.

The biggest thing is that most modern digital scopes, in their quest to do everything under the sun, have become extremely complicated, and their UI is often a pain in the backside. It's great to be able to do really advanced things, but the really advanced stuff is 5% of my time using a scope, and if I just need to trace a sine wave through a 500 kHz bandwidth amplifier, the less I have to mess with things, the better.

Furthermore... on an analog scope, you can immediately tell exactly how it is configured without touching it. This is not the case with digital scopes, and this is a real pain - I find that I make far more bonehead measurement errors with really modern scopes than I do with those from yesteryear.

I really like my Siglent scope, and I really like the Tek scopes at work - both the TDS3054s and the new ones (I don't remember the model number) we've gotten recently. That said, I still reach for my 54622A and my Tek 2235 more often than I reach for my newer, higher-performance scopes, and this is because for a good portion of what I do, the 54622A is fast enough, and it is far less likely to annoy me than anything more recent. I actually like the TDS220 series for this reason - it's pretty usable.

Also, I'm profoundly lazy. Do you seriously think that I'm going to mess around with a software utility or a USB stick every time I want to save a scope image? Unless this is going in a formal report (or has intellectual property issues) I'm going to snap a picture with my phone. Incidentally, CRTs tend to photograph really well.

And finally, I don't have to put a brick of lead behind my analog scope to stop it from sliding across the bench when I try to connect a probe to it.


So aside from the satisfaction of using a good analog oscilloscope (the appearance of the traces on a CRT, the tactile feel of switches, etc), the main advantage they still hold has more to do with the user interface on a lot of modern scopes.

All remarkably sane points that mirror my experience and opinion.

My principal objection is to people that say don't consider buying an analogue scope (especially if they have financial interest in digitising scopes!). A working analogue scope is an extremely useful tool that you can learn to use quickly and easily. If it is less expensive than a new digitising scope, then there is more money available for other necessities, e.g. the right type of probe for the measurement being made.
Title: Re: True analog scopes
Post by: 2N3055 on December 15, 2022, 09:59:48 am
I admit that my 2235 sees a whole lot less use than it used to.

That said, there are some things that the classic Tek analog scopes do better than modern digital scopes.

The biggest thing is that most modern digital scopes, in their quest to do everything under the sun, have become extremely complicated, and their UI is often a pain in the backside. It's great to be able to do really advanced things, but the really advanced stuff is 5% of my time using a scope, and if I just need to trace a sine wave through a 500 kHz bandwidth amplifier, the less I have to mess with things, the better.

Furthermore... on an analog scope, you can immediately tell exactly how it is configured without touching it. This is not the case with digital scopes, and this is a real pain - I find that I make far more bonehead measurement errors with really modern scopes than I do with those from yesteryear.

I really like my Siglent scope, and I really like the Tek scopes at work - both the TDS3054s and the new ones (I don't remember the model number) we've gotten recently. That said, I still reach for my 54622A and my Tek 2235 more often than I reach for my newer, higher-performance scopes, and this is because for a good portion of what I do, the 54622A is fast enough, and it is far less likely to annoy me than anything more recent. I actually like the TDS220 series for this reason - it's pretty usable.

Also, I'm profoundly lazy. Do you seriously think that I'm going to mess around with a software utility or a USB stick every time I want to save a scope image? Unless this is going in a formal report (or has intellectual property issues) I'm going to snap a picture with my phone. Incidentally, CRTs tend to photograph really well.

And finally, I don't have to put a brick of lead behind my analog scope to stop it from sliding across the bench when I try to connect a probe to it.


So aside from the satisfaction of using a good analog oscilloscope (the appearance of the traces on a CRT, the tactile feel of switches, etc), the main advantage they still hold has more to do with the user interface on a lot of modern scopes.

All remarkably sane points that mirror my experience and opinion.

My principal objection is to people that say don't consider buying an analogue scope (especially if they have financial interest in digitising scopes!). A working analogue scope is an extremely useful tool that you can learn to use quickly and easily. If it is less expensive than a new digitising scope, then there is more money available for other necessities, e.g. the right type of probe for the measurement being made.

You live in the past. Your advice stood and was good advice 10-15 years ago.
There are very few good, still working, old CRT scopes available at affordable prices.
Those being sold now are sold at "vintage" "legendary" prices. You might get lucky occasionally in some countries (USA, UK, maybe France or Germany). Those few that are in perfect condition are being kept by people like you and treasured.

300€ buys you solid, brand new (with warranty) modern digital scope that does everything needed today.
Those that (by choice) like dealing with outdated technology, both in choice of instruments and things you design and repair should stick with whatever they think is appropriate..

For 300€ you cannot buy good working old CRT Tek scope, even 20 MHz one...
Title: Re: True analog scopes
Post by: tggzzz on December 15, 2022, 10:24:12 am
I admit that my 2235 sees a whole lot less use than it used to.

That said, there are some things that the classic Tek analog scopes do better than modern digital scopes.

The biggest thing is that most modern digital scopes, in their quest to do everything under the sun, have become extremely complicated, and their UI is often a pain in the backside. It's great to be able to do really advanced things, but the really advanced stuff is 5% of my time using a scope, and if I just need to trace a sine wave through a 500 kHz bandwidth amplifier, the less I have to mess with things, the better.

Furthermore... on an analog scope, you can immediately tell exactly how it is configured without touching it. This is not the case with digital scopes, and this is a real pain - I find that I make far more bonehead measurement errors with really modern scopes than I do with those from yesteryear.

I really like my Siglent scope, and I really like the Tek scopes at work - both the TDS3054s and the new ones (I don't remember the model number) we've gotten recently. That said, I still reach for my 54622A and my Tek 2235 more often than I reach for my newer, higher-performance scopes, and this is because for a good portion of what I do, the 54622A is fast enough, and it is far less likely to annoy me than anything more recent. I actually like the TDS220 series for this reason - it's pretty usable.

Also, I'm profoundly lazy. Do you seriously think that I'm going to mess around with a software utility or a USB stick every time I want to save a scope image? Unless this is going in a formal report (or has intellectual property issues) I'm going to snap a picture with my phone. Incidentally, CRTs tend to photograph really well.

And finally, I don't have to put a brick of lead behind my analog scope to stop it from sliding across the bench when I try to connect a probe to it.


So aside from the satisfaction of using a good analog oscilloscope (the appearance of the traces on a CRT, the tactile feel of switches, etc), the main advantage they still hold has more to do with the user interface on a lot of modern scopes.

All remarkably sane points that mirror my experience and opinion.

My principal objection is to people that say don't consider buying an analogue scope (especially if they have financial interest in digitising scopes!). A working analogue scope is an extremely useful tool that you can learn to use quickly and easily. If it is less expensive than a new digitising scope, then there is more money available for other necessities, e.g. the right type of probe for the measurement being made.

You live in the past. Your advice stood and was good advice 10-15 years ago.
There are very few good, still working, old CRT scopes available at affordable prices.
Those being sold now are sold at "vintage" "legendary" prices. You might get lucky occasionally in some countries (USA, UK, maybe France or Germany). Those few that are in perfect condition are being kept by people like you and treasured.

300€ buys you solid, brand new (with warranty) modern digital scope that does everything needed today.
Those that (by choice) like dealing with outdated technology, both in choice of instruments and things you design and repair should stick with whatever they think is appropriate..

For 300€ you cannot buy good working old CRT Tek scope, even 20 MHz one...

Look harder; they are still around.

The rule-of-thumb-price is still £$1/MHz. I can see half a dozen on fleabay/gumtree all displaying sensible traces (all in the UK), all with asking prices in the £40-80 range. Brands are Philips, Gould, Telequipment, even HP.

Even a 20MHz scope is better than none, and I'd rather pay £20 than £300, since I would also have money for probes (inc HV differential) bench PSUs, bench meters etc.

There are of course scopes with ridiculous asking prices. Basing an argument on ridiculous prices is as ridiculous as the prices themselves.
Title: Re: True analog scopes
Post by: 2N3055 on December 15, 2022, 11:38:22 am

Look harder; they are still around.

The rule-of-thumb-price is still £$1/MHz. I can see half a dozen on fleabay/gumtree all displaying sensible traces (all in the UK), all with asking prices in the £40-80 range. Brands are Philips, Gould, Telequipment, even HP.

Even a 20MHz scope is better than none, and I'd rather pay £20 than £300, since I would also have money for probes (inc HV differential) bench PSUs, bench meters etc.

There are of course scopes with ridiculous asking prices. Basing an argument on ridiculous prices is as ridiculous as the prices themselves.

Yeah all of those are shooting in the dark.. More crap than good ones. And as I said, if I buy from UK or USA, I pay shipping on a 20 kg boat anchor that comes broken from shipping, and then customs and VAT on the combined sum....
Even 20 GBP becomes 150€ for 40 year old crap in unknown state, brittle plastic and bent frame from shipping. Not really a "great deal".

At the same time I can buy something brand new with warranty that works great, and is better than any of that crap...

That is why I said : Tektronix 2465 in NOS state would be worth having. And would require king's ransom...

I understand that you can go to local HAM swap meet and sometimes stumble on something decent for 20 quids.... And no other costs.. Great for you. In most of other countries it is not so. Unfortunately so. I wish you were right. But it is not.
Title: Re: True analog scopes
Post by: TimFox on December 15, 2022, 02:54:42 pm
To the last half-dozen posts:
Owning both types of 'scope, my general rule is
--When I don't know what's wrong or going on, use the analog CRO.
--When I do know what's happening, but need to measure it, use the DSO.
Title: Re: True analog scopes
Post by: mawyatt on December 15, 2022, 03:14:44 pm
We had to purchase 4 Tek scopes to get two in actual working order, one literally blew up while just warming up (infamous RIFA cap). So we now have 2 beautiful Tek 2465 analog scopes that have been restored with countless hours for power supply recapping, troubleshooting, cleaning and main PCBs recapping. One required an extremely delicate ceramic hybrid input attenuator modules repair & rebuild, another required troubleshooting the defective scope cal and all required extensive cleaning & recapping. So 100s of hours invested in studying, troubleshooting and restoring each 2465 and ~$100 in replacement caps and components.

Was this fun? You bet!! Would one do this if they didn't enjoy restoring these old relics, and needed a working scope right away that they could rely on for income? Probably not!!

As far as analog vs digital scope discussion, the 2465s hardly ever get used and only for an occasional revisit to past, fun to play with but we never utilize them for any serious work anymore.

Why? Because the modern DSO has replaced almost every measurement need we've encountered, then some we didn't even think about!! Of course one must have the skill and knowledge to use such, and they do require a "learning curve" just like any new instrument that's to be used to perfection.

We've used just about every analog scope Tek has made over the past 60+ years, and a few from HP, B&K, Heathkit, Iwatsu and others, and are an old engrained analog type that wasn't fond of DSOs in our lab back before retiring, altho didn't get in the labs much then (another story).

After realizing our narrow minded short-comes, we decided to acquire a DSO and "Spend the necessary time without prejudice to learn this new to us instrument". Only regret is we should have realized the benefits of these DSOs a decade earlier  ???

Of course YMMY!!

Best,
Title: Re: True analog scopes
Post by: BillyO on December 15, 2022, 03:43:38 pm
My Tek 465 works perfectly.  It gets used frequently as I just like dealing with quality.  If I don't need a DSO's "features" or don't need bandwidth in excess of 100MHz, I use the Tek.  It's from a time where quality was paramount.  Tek scopes to day can't hold a candle to it's beautiful, solid build, let alone mi Siglents.
Title: Re: True analog scopes
Post by: Fungus on December 15, 2022, 04:08:49 pm
I'm skeptical that anyone is actually producing new analog scopes anymore.

Just go on digikey (or whatever) and filter the oscilloscopes by "CRT"
Title: Re: True analog scopes
Post by: TimFox on December 15, 2022, 04:48:19 pm
I did that search on DigiKey, specifying "active" instead of "obsolete", and it returned only one B&K Precision 2120C 30 MHz unit, lead time 10 weeks.
Title: Re: True analog scopes
Post by: switchabl on December 15, 2022, 05:02:16 pm
I really like my Siglent scope, and I really like the Tek scopes at work - both the TDS3054s and the new ones (I don't remember the model number) we've gotten recently. That said, I still reach for my 54622A and my Tek 2235 more often than I reach for my newer, higher-performance scopes, and this is because for a good portion of what I do, the 54622A is fast enough, and it is far less likely to annoy me than anything more recent. I actually like the TDS220 series for this reason - it's pretty usable.

I have an Agilent 2000X for that. As a DSO, it is now somewhat outdated (in particular it has pretty limited memory). But it is an amazing CRT emulator. >:D It responds instantly and basically "just works" with minimal fiddling. I still have a nice analog Tektronix somewhere but I'm keeping it purely for the nostalgia (along with a couple of Hamegs). I can't think of anything that would make me actually want to use it again for real.

I have no love for the TDS220 though. Yes, in many ways it was quite revolutionary in its day (form factor, 1GS/s at low price point). But it was slow and had an awful screen without intensity grading. It was also ubiquitous (particularly in the education sector) and frankly, it gave DSOs a bad name.
Title: Re: True analog scopes
Post by: Fungus on December 15, 2022, 05:04:50 pm
I did that search on DigiKey, specifying "active" instead of "obsolete", and it returned only one B&K Precision 2120C 30 MHz unit, lead time 10 weeks.

Aliexpress has a few, you can even get a round-screen one for real retro effect:

https://www.alibaba.com/product-detail/Analog-oscilloscope-oscilloscope-oscilloscope-price-J2459_60008202178.html (https://www.alibaba.com/product-detail/Analog-oscilloscope-oscilloscope-oscilloscope-price-J2459_60008202178.html)

There's also some scary-expensive ones:

https://www.aliexpress.com/item/1005004032050364.html (https://www.aliexpress.com/item/1005004032050364.html)
Title: Re: True analog scopes
Post by: Mechatrommer on December 15, 2022, 05:22:01 pm
I did that search on DigiKey, specifying "active" instead of "obsolete", and it returned only one B&K Precision 2120C 30 MHz unit, lead time 10 weeks.
Aliexpress has a few, you can even get a round-screen one for real retro effect:
https://www.alibaba.com/product-detail/Analog-oscilloscope-oscilloscope-oscilloscope-price-J2459_60008202178.html (https://www.alibaba.com/product-detail/Analog-oscilloscope-oscilloscope-oscilloscope-price-J2459_60008202178.html)
did you look what kind of joke is that? BNC input, peculiar control knobs and marking, 2MHz? forget uV/div, forget cursors for noise measurement, and forget anything mentioned here about whats good in CRO.
Title: Re: True analog scopes
Post by: Fungus on December 15, 2022, 05:22:18 pm
did you look what kind of joke is that? (the retro one) BNC input, peculiar control knobs and marking, 2MHz? forget uV/div, forget cursors for noise measurement, and forget anything mentioned here about whats good in CRO. even on the more expensive unit you linked.. try something better...

The assertion was "I'm skeptical that anyone is actually producing new analog scopes anymore. "  :-//

Some people obviously are.
Title: Re: True analog scopes
Post by: JPortici on December 15, 2022, 06:10:58 pm
One good use for analog scopes: movie prop, they look so much better as a prop than digital scopes.
Except in medical dramas, in those the higher tech the better
Title: Re: True analog scopes
Post by: xrunner on December 15, 2022, 06:15:34 pm
One good use for analog scopes: movie prop, they look so much better as a prop than digital scopes.
Except in medical dramas, in those the higher tech the better

Or cartoons ...

(https://www.eevblog.com/forum/testgear/true-analog-scopes/?action=dlattach;attach=1664794;image)
Title: Re: True analog scopes
Post by: tggzzz on December 15, 2022, 06:29:55 pm

Look harder; they are still around.

The rule-of-thumb-price is still £$1/MHz. I can see half a dozen on fleabay/gumtree all displaying sensible traces (all in the UK), all with asking prices in the £40-80 range. Brands are Philips, Gould, Telequipment, even HP.

Even a 20MHz scope is better than none, and I'd rather pay £20 than £300, since I would also have money for probes (inc HV differential) bench PSUs, bench meters etc.

There are of course scopes with ridiculous asking prices. Basing an argument on ridiculous prices is as ridiculous as the prices themselves.

Yeah all of those are shooting in the dark.. More crap than good ones. And as I said, if I buy from UK or USA, I pay shipping on a 20 kg boat anchor that comes broken from shipping, and then customs and VAT on the combined sum....
Even 20 GBP becomes 150€ for 40 year old crap in unknown state, brittle plastic and bent frame from shipping. Not really a "great deal".

At the same time I can buy something brand new with warranty that works great, and is better than any of that crap...

That is why I said : Tektronix 2465 in NOS state would be worth having. And would require king's ransom...

I understand that you can go to local HAM swap meet and sometimes stumble on something decent for 20 quids.... And no other costs.. Great for you. In most of other countries it is not so. Unfortunately so. I wish you were right. But it is not.

And if you were in Antartica, as some denizens of this forum claim, shipping would be even more expensive. So what?! Ditto the more realistic example of Brazil.

Don't presume the conditions in Croatia are the same anywhere else. Don't presume the choices and appropriate decisions are the same.

Note that, unlike you, I qualified my statements, viz "in the UK".
Title: Re: True analog scopes
Post by: tggzzz on December 15, 2022, 06:39:05 pm
We had to purchase 4 Tek scopes to get two in actual working order, one literally blew up while just warming up (infamous RIFA cap). So we now have 2 beautiful Tek 2465 analog scopes that have been restored with countless hours for power supply recapping, troubleshooting, cleaning and main PCBs recapping. One required an extremely delicate ceramic hybrid input attenuator modules repair & rebuild, another required troubleshooting the defective scope cal and all required extensive cleaning & recapping. So 100s of hours invested in studying, troubleshooting and restoring each 2465 and ~$100 in replacement caps and components.

Was this fun? You bet!! Would one do this if they didn't enjoy restoring these old relics, and needed a working scope right away that they could rely on for income? Probably not!!

As far as analog vs digital scope discussion, the 2465s hardly ever get used and only for an occasional revisit to past, fun to play with but we never utilize them for any serious work anymore.

Why? Because the modern DSO has replaced almost every measurement need we've encountered, then some we didn't even think about!! Of course one must have the skill and knowledge to use such, and they do require a "learning curve" just like any new instrument that's to be used to perfection.

We've used just about every analog scope Tek has made over the past 60+ years, and a few from HP, B&K, Heathkit, Iwatsu and others, and are an old engrained analog type that wasn't fond of DSOs in our lab back before retiring, altho didn't get in the labs much then (another story).

After realizing our narrow minded short-comes, we decided to acquire a DSO and "Spend the necessary time without prejudice to learn this new to us instrument". Only regret is we should have realized the benefits of these DSOs a decade earlier  ???

Of course YMMY!!

Best,

...all sensible points!

A modern medium-to-high end digitising scope really is a miracle of technological advance. But that is far less clear for a low-end or decade old digitising scope.

Unfortunately I have heard too many people saying they want a digitial scope solely because of the auto-setup button. On further questioning, they actively don't want to learn what's in a scope, nor its pitfalls and traps, nor how to get the best from it.

I haven't tested whether those people would also like a Tesla "full driving (beta)" car for similar reasons. I suspect so :(
Title: Re: True analog scopes
Post by: Fungus on December 15, 2022, 06:42:40 pm
Unfortunately I have heard too many people saying they want a digitial scope solely because of the auto-setup button. On further questioning, they actively don't want to learn what's in a scope, nor its pitfalls and traps, nor how to get the best from it.

Micsigs have a mode where they continuously adjust the horizontal/vertical scale to track the input signal - no need to press a button!  :)

Title: Re: True analog scopes
Post by: rf-loop on December 15, 2022, 06:48:23 pm

Unfortunately I have heard too many people saying they want a digitial scope solely because of the auto-setup button. On further questioning, they actively don't want to learn what's in a scope, nor its pitfalls and traps, nor how to get the best from it.

I haven't tested whether those people would also like a Tesla "full driving (beta)" car for similar reasons. I suspect so :(

 :-DD :clap: :clap: :clap:
Title: Re: True analog scopes
Post by: 2N3055 on December 15, 2022, 07:08:23 pm

And if you were in Antartica, as some denizens of this forum claim, shipping would be even more expensive. So what?! Ditto the more realistic example of Brazil.
:-//
Title: Re: True analog scopes
Post by: bdunham7 on December 15, 2022, 07:22:01 pm
For 300€ you cannot buy good working old CRT Tek scope, even 20 MHz one...

To be fair, this may be true for you, but isn't the same everywhere.  Of course local conditions will make a difference in these sort of things.  In the past few years I've sold some fairly nice scopes with (unofficial) calibration and warranty for under $300.  I paid $29 each for a Tek 2445 and a Kikusui COS5100 and both were completely in working order.  The deals aren't quite that good these days, but if I were selling either of those today I would not expect over $300.  And they're both actually pretty good scopes. 
Title: Re: True analog scopes
Post by: tggzzz on December 15, 2022, 07:42:25 pm

And if you were in Antartica, as some denizens of this forum claim, shipping would be even more expensive. So what?! Ditto the more realistic example of Brazil.
:-//

From that we can infer you didn't bother to read the part of my post that you snipped. Unimpressive.
Title: Re: True analog scopes
Post by: tautech on December 15, 2022, 08:02:13 pm
One good use for analog scopes: movie prop, they look so much better as a prop than digital scopes.
Except in medical dramas, in those the higher tech the better
Of course, directors and set techs have no idea of how to use any scope let alone a DSO.  ::)

Yet if the chap they hired one from spends a minute getting it to do something rather than be a wall hanging it can become near the centerpiece of the shot:

https://www.youtube.com/watch?v=w4Ywo3rX7a0 (https://www.youtube.com/watch?v=w4Ywo3rX7a0)
Title: Re: True analog scopes
Post by: Mechatrommer on December 15, 2022, 08:41:43 pm
i dont mind movie prop, but i wonder when human can travel in hyperspace, they still use CRO to find and lock radio frequency, go watch Star Wars Rogue One if you dont believe me.
Title: Re: True analog scopes
Post by: 2N3055 on December 15, 2022, 08:57:49 pm

And if you were in Antartica, as some denizens of this forum claim, shipping would be even more expensive. So what?! Ditto the more realistic example of Brazil.
:-//

From that we can infer you didn't bother to read the part of my post that you snipped. Unimpressive.

I didn't try to impress you. Impressing anonymous people in faraway lands holds very little value to me.
No, I simply did not understand what you wrote...  What "more realistic example of Brazil" are you referring to... I don't see any example. And Antarctica comment plays in my favour not yours..  Hence confusion on my side..
And I did say where my statements did not apply. And said that I agree in UK is as you say. And that, exactly as you, I said that experience in your country is no indicator whatsoever of other countries. So, again, confusion. We basically agree in principle, it is not the same in every country. This discussion has happened many times before. People from many countries across globe said same as I did: it is not so easy..

To make sure , I'm NOT against CRT scopes or people that like them. I also think there are many types of work where they are good enough to do the job. And if you like them and can get a good one for a good price and you know the limitations, go for it by all means. If you have a good one, don't throw it away. These are nice machines that are still useful... And if they are enough for you that is awesome..

But to a question by OP: no, no good CRT scopes are still being produced and no there is no application where CRT scope would be better (in sense : is there a job in electronics that cannot be done with DSO). And yes there are  literally dozens of types of work that could not be done with CRT scopes, but are easily done with a DSO...

There is a reason they are not being made anymore. Nobody needs them for real work...DSOs are more useful. And apparently not that hard to learn, as evidenced by God knows of how many millions of DSO users...

For hobby users, they do as they please. It doesn't have to be best or most rational thing.

But to a question on a car forum "What is a good, simple, reliable car that you recommend me to buy?" best answer is not "WV Beetle".. Even if there could be few around that are being kept in working condition and are registered and driving..
Title: Re: True analog scopes
Post by: TimFox on December 15, 2022, 09:13:22 pm
One good use for analog scopes: movie prop, they look so much better as a prop than digital scopes.
Except in medical dramas, in those the higher tech the better

An example of when a CRT CRO was a necessary prop for a movie plot: in "Journey to the Far Side of the Sun" (aka "Doppelgänger") from 1969, I immediately knew something was amiss when the Tektronix 541 oscilloscope had its CRT in the upper right corner of the panel.
https://www.imdb.com/title/tt0064519/ (https://www.imdb.com/title/tt0064519/)

Title: Re: True analog scopes
Post by: vk6zgo on December 15, 2022, 11:43:04 pm
I really like my Siglent scope, and I really like the Tek scopes at work - both the TDS3054s and the new ones (I don't remember the model number) we've gotten recently. That said, I still reach for my 54622A and my Tek 2235 more often than I reach for my newer, higher-performance scopes, and this is because for a good portion of what I do, the 54622A is fast enough, and it is far less likely to annoy me than anything more recent. I actually like the TDS220 series for this reason - it's pretty usable.

I have an Agilent 2000X for that. As a DSO, it is now somewhat outdated (in particular it has pretty limited memory). But it is an amazing CRT emulator. >:D It responds instantly and basically "just works" with minimal fiddling. I still have a nice analog Tektronix somewhere but I'm keeping it purely for the nostalgia (along with a couple of Hamegs). I can't think of anything that would make me actually want to use it again for real.

I have no love for the TDS220 though. Yes, in many ways it was quite revolutionary in its day (form factor, 1GS/s at low price point). But it was slow and had an awful screen without intensity grading. It was also ubiquitous (particularly in the education sector) and frankly, it gave DSOs a bad name.

I think they had "a bad name" well before the poor old "Tedious 220".
HP & Tek went "boots & all" into the early DSOs, well before they were usable in anything but "niche" applications, & as I recounted earlier, would try to sell them to people who needed consistent performance, which they were unable to offer.

They were useless at long time/div settings, unless you were looking at sinewaves, so were regarded with suspicion by many of us, who had been "digital friendly" before encountering them.

On top of that, they were all CRT devices, anyway, so either used normal sized CRO style tubes with similar sized display to their analogue counterparts, or TV style tubes with electromagnetic scanning.

At least, by the time the TDS 210 & 220 came along, some of those shortcomings had been addressed.
How many, I don't know, as I have never played with one, but the very small memory size, militates against usability for, say, analogue video.

If I could pick up a TDS220 for, say, $A150.00, I would get one, just for fun, but prices for them on ebay are ridiculous.
Title: Re: True analog scopes
Post by: baldurn on December 15, 2022, 11:47:05 pm

Yet if the chap they hired one from spends a minute getting it to do something rather than be a wall hanging it can become near the centerpiece of the shot:

Good one. Notice how the actor is _not_ touching the oscilloscope. He appears to be fiddling with a power supply not connected to anything. Can't be trusted not to ruin anything more advanced  :-DD
Title: Re: True analog scopes
Post by: tautech on December 16, 2022, 12:09:49 am

Yet if the chap they hired one from spends a minute getting it to do something rather than be a wall hanging it can become near the centerpiece of the shot:

Good one. Notice how the actor is _not_ touching the oscilloscope. He appears to be fiddling with a power supply not connected to anything. Can't be trusted not to ruin anything more advanced  :-DD
:horse:
Do you not know you're not supposed to inspect advertising too carefully ?

All I got was a ker ching $, thank you very much !
My PSU, scope, AWG, AVO and some component storage props and other stuff too.
Came home with a busted HP1740 as a perk and really can't be stuffed fixing the darn thing as even a cheap DSO will kick it in the arse.
Title: Re: True analog scopes
Post by: vk6zgo on December 16, 2022, 12:37:58 am
I did that search on DigiKey, specifying "active" instead of "obsolete", and it returned only one B&K Precision 2120C 30 MHz unit, lead time 10 weeks.
Aliexpress has a few, you can even get a round-screen one for real retro effect:
https://www.alibaba.com/product-detail/Analog-oscilloscope-oscilloscope-oscilloscope-price-J2459_60008202178.html (https://www.alibaba.com/product-detail/Analog-oscilloscope-oscilloscope-oscilloscope-price-J2459_60008202178.html)
did you look what kind of joke is that? BNC input, peculiar control knobs and marking, 2MHz? forget uV/div, forget cursors for noise measurement, and forget anything mentioned here about whats good in CRO.

It is a seriously weird device.

At first sight, it looks like my little "Digitech" thing, but that is a 10MHz device, with BNC inputs, uV/div & usec/div switches, switchable AC/DC coupling, X/Y inputs, Auto, Normal, Line (Mains freq), & Analog video H & V Triggering.
"Cursors"? ----they were pretty rare on Analogue 'scopes, apart from HP, Tek, & their direct competitors back in the day.

Mine has the same peculiar knobs (they fall off after a while), but knobs can be replaced.

A bit more serious is that the BNCs have minimal thread length & tend to come unscrewed but are replaceable with better ones.
My Digitech had a "EHT" supply failure, but the replacement of one transistor from my junkbox restored it.

Overall, the "proper one" is a usable, if basic 'scope, which is certainly more functional than some of the silly little so-called "DSOs" appearing on ebay for less than $A100.00.

That said, why anyone would "dumb down" an already pretty basic device is beyond me!

PS--Did I mention it is tiny? (About the same package size as a hp 410C, but a little skinnier, & slightly taller).

I described it once on this forum as looking like something "Cabbage Patch" dolls would use! ;D
Title: Re: True analog scopes
Post by: vk6zgo on December 16, 2022, 12:44:15 am
Unfortunately I have heard too many people saying they want a digitial scope solely because of the auto-setup button. On further questioning, they actively don't want to learn what's in a scope, nor its pitfalls and traps, nor how to get the best from it.

Micsigs have a mode where they continuously adjust the horizontal/vertical scale to track the input signal - no need to press a button!  :)

It is hard to think of a more annoying feature!
Title: Re: True analog scopes
Post by: BillyO on December 16, 2022, 01:26:46 am
BNC input  ..

BNC input?  They don' need no stinkin' BNC input!
Title: Re: True analog scopes
Post by: jonpaul on December 16, 2022, 02:15:50 am
Rebonjour,

Having used Lecroy, TEK and Yokogawa digitals since 1993, they are great in some uses like transient capture, storage or saving the images.

But NONE can do a real X-Y  Lissajous well or easily, (used in Audio and time measurements among other applications)


Many DSO lack the Analog  CH1-CH2 or CH 2 INV function to get a differential  view.
Finally the lowest sesnitivity is nowhere as good as a fine analog TEK plugin for 7000.


Regarding cost of analog scopes, my finds in the last year...Two  Hameg German design, made in France,1980s


HM103, EU 5 at Paris street sale...works fine 1 ch 10 MHz!

HM204 EU 25 another street sale 20 MHz 2 ch
Includes a handy Lissajous component curve tester!
Perfect for 99% of basic audio and museum troubleshooting and tests, in a small apartment lab.

Also  TEK 475, fixed up the HV mult, bottom feet are crumbling, still works!

VIVE L'ANALOGIQUE!

bon soiree!

Jon



Title: Re: True analog scopes
Post by: H713 on December 16, 2022, 04:39:13 am
Yes, in some parts of the world, getting a "working CRT scope" is hard. Has it ever been easy? I don't have an answer for that, but doubtful.

In the US (which, incidentally, is a fairly significant number of people!), that is far from the case. Over the past two or three years, I've picked up half a dozen analog scopes, all at least 100 MHz (mostly Tektronix, Kenwood, etc) for about $50 each - and I've passed up a whole lot more that I didn't want to deal with. None were listed as working, but none of them (except the 454A that I way overpaid for) had any significant issues. This stuff still turns up at surplus auctions and hamfests. Most universities still have piles of these things sitting in labs and storage rooms, and they come available every time their is a cleaning operation. There are a lot of Tektronix 2215s and 2235s kicking around - they sold an insane number of these things.

Keep in mind, I live in southern Wisconsin, where most storage facilities are filled with rotting taxidermy, dead snowmobiles and 3000-year-old C-scows. In other parts of the country, old test equipment is significantly more prevalent.

Again, this stuff was pretty reliable. The reason that there are so many dead ones on eBay is that the same dead scopes keep getting resold.

If I could only have one scope? Certainly digital, and unless you're given an analog one for free, your first scope should probably be a digital scope at this point, simply because it can do more. But once you have that, a good analog scope is still rather nice to have around.

A last worthwhile point I'll make is this:
Fast digital scopes are marvel of signal processing, fast analog scopes are a marvel of physics.
Title: Re: True analog scopes
Post by: tautech on December 16, 2022, 04:55:14 am
Many DSO lack the Analog  CH1-CH2 or CH 2 INV function to get a differential  view.
Really you have no idea what features are in the modern DSO, none at all !
Minus is a very common Math function and Invert is a channel menu feature both of which are top level menu items in their respective places.........NOT front panel buttons or switches !
Further these 2 functions (Minus Math and Invert) appear in channel tabs plain as day so not to divert the eye away from where the action is really happening......on the display !

Is it because of EASL or are datasheets and manuals difficult for you to understand ?

Like I mentioned before you could really benefit from getting a modern DSO to learn what they really can do instead of some decades old blinkered incorrect opinion.



Title: Re: True analog scopes
Post by: Mechatrommer on December 16, 2022, 05:45:14 am
BNC input  ..
BNC input?  They don' need no stinkin' BNC input!
i meant banana jack. how could i made such mistake? :palm:

Many DSO lack the Analog  CH1-CH2 or CH 2 INV function to get a differential  view.
Really you have no idea what features are in the modern DSO, none at all !
Minus is a very common Math function and Invert is a channel menu feature both of which are top level menu items in their respective places.........NOT front panel buttons or switches !
Further these 2 functions (Minus Math and Invert) appear in channel tabs plain as day so not to divert the eye away from where the action is really happening......on the display !

Is it because of EASL or are datasheets and manuals difficult for you to understand ?

Like I mentioned before you could really benefit from getting a modern DSO to learn what they really can do instead of some decades old blinkered incorrect opinion.
(EASL)? what CRO got to do with Liver association or EA basketball league? ;D btw if SW math is not preferable, being slow as its excuse. buy differential probe, or make an inverting opamp (of differential probe input in reverse), they are jellybean cheap today. a very good differential CH2-CH1 (high CMRR @ high BW) is not cheap anyway, today and before. if big names like Tek/Keysight/Lecroy/R&S opted to remove that features from DSO, there must be due to some logical reason. dont be a person who want to buy CRO just because it has CH1-CH2 or CH 2 INV HW function. just as a person who want to buy DSO just because Auto button, they are very minority here though, or beginner who just came here ready to be educated.
Title: Re: True analog scopes
Post by: tautech on December 16, 2022, 06:00:02 am
Many DSO lack the Analog  CH1-CH2 or CH 2 INV function to get a differential  view.
Really you have no idea what features are in the modern DSO, none at all !
Minus is a very common Math function and Invert is a channel menu feature both of which are top level menu items in their respective places.........NOT front panel buttons or switches !
Further these 2 functions (Minus Math and Invert) appear in channel tabs plain as day so not to divert the eye away from where the action is really happening......on the display !

Is it because of EASL or are datasheets and manuals difficult for you to understand ?

Like I mentioned before you could really benefit from getting a modern DSO to learn what they really can do instead of some decades old blinkered incorrect opinion.
(EASL)?
English as second language......what other excuse is there for such grossly wrong thinking ?

We each have a responsibility to those that come after to provide the best correct and latest information not some ramblings from last century.

Quote
or beginner who just came here ready to be educated.
This is our responsibility ^^^ to provide accurate and correct facts.

Take the topic of this thread and ask whom manufacturers a CRT TV or monitor today and then ask who in these energy challenged times would want to use one ?

At one time walked then we used horses to pull carts then made cars and then planes....it's called progress and difficult for some to fathom or accept.  ::)
Title: Re: True analog scopes
Post by: Mechatrommer on December 16, 2022, 06:43:48 am
English as second language......what other excuse is there for such grossly wrong thinking ?
if EASL is a problem, we have TESL (https://www.hotcoursesabroad.com/study-in-malaysia/visa-guides/what-is-tesl/) very well accepted in academic level. ;) the usual reasons imho is lack of googling, or hard to get rid old habit (i also have this syndrome in computer programming and CAD notions)

At one time walked then we used horses to pull carts then made cars and then planes....it's called progress and difficult for some to fathom or accept.  ::)
but people can still argue horses dont need gas, not poluting environment, no need dedicated parking lot or lane and other sane reasons. at least i saw in movie, some police dept or enforcement still use horses in 1st world.. so people can use the analogy to stick with CRO, but for the above said unreasonable reason (fallacy). ymmv.
Title: Re: True analog scopes
Post by: Fungus on December 16, 2022, 07:18:55 am
Unfortunately I have heard too many people saying they want a digitial scope solely because of the auto-setup button. On further questioning, they actively don't want to learn what's in a scope, nor its pitfalls and traps, nor how to get the best from it.

Micsigs have a mode where they continuously adjust the horizontal/vertical scale to track the input signal - no need to press a button!  :)

It is hard to think of a more annoying feature!

Depends on the implementation. Watch this video at the 12:40 mark before deciding:

https://www.youtube.com/watch?v=i8NkppAvEQI (https://www.youtube.com/watch?v=i8NkppAvEQI)

He leaves it on for most of the video. Just watch...
Title: Re: True analog scopes
Post by: Mechatrommer on December 16, 2022, 07:31:38 am
Unfortunately I have heard too many people saying they want a digitial scope solely because of the auto-setup button. On further questioning, they actively don't want to learn what's in a scope, nor its pitfalls and traps, nor how to get the best from it.
Micsigs have a mode where they continuously adjust the horizontal/vertical scale to track the input signal - no need to press a button!  :)
It is hard to think of a more annoying feature!
Depends on the implementation. Watch this video at the 12:40 mark before deciding:
some people make fun of Auto feature in DSO, but at the same time the same person wants everythings "managed" automatically from behind when discussing in Programming Language section...  On further questioning, they actively don't want to learn what's in a programming language, nor its pitfalls and traps, nor how to get the best from it... ;D btw, i'm "manual car" type of guy, so i dont use Auto feature very much, the same in (C/C++) programming language. cheers.
Title: Re: True analog scopes
Post by: MegaVolt on December 16, 2022, 08:38:59 am
Just go on digikey (or whatever) and filter the oscilloscopes by "CRT"
Unfortunately this won't work. The presence of a CRT monitor does not guarantee that the oscilloscope is analog. HP/Agilent produced digital oscilloscopes with CRT monitors.
Title: Re: True analog scopes
Post by: tautech on December 16, 2022, 10:46:46 am
English as second language......what other excuse is there for such grossly wrong thinking ?
if EASL is a problem, we have TESL (https://www.hotcoursesabroad.com/study-in-malaysia/visa-guides/what-is-tesl/) very well accepted in academic level. ;) the usual reasons imho is lack of googling, or hard to get rid old habit (i also have this syndrome in computer programming and CAD notions)

At one time walked then we used horses to pull carts then made cars and then planes....it's called progress and difficult for some to fathom or accept.  ::)
but people can still argue horses dont need gas, not poluting environment,...........
They can and will go hungry.
Title: Re: True analog scopes
Post by: tggzzz on December 16, 2022, 10:48:06 am
or beginner who just came here ready to be educated.
This is our responsibility ^^^ to provide accurate and correct facts.

Correct.

And I know the accurate and correct facts.
Title: Re: True analog scopes
Post by: rf-loop on December 16, 2022, 11:22:02 am
Just go on digikey (or whatever) and filter the oscilloscopes by "CRT"
Unfortunately this won't work. The presence of a CRT monitor does not guarantee that the oscilloscope is analog. HP/Agilent produced digital oscilloscopes with CRT monitors.

Also Tektronix and some others. All ( tens of) HP digital oscilloscopes what I have owned and used as I remember all have raster CRT including also 1GHz 54111D. 
But Tektronix "CRT" digital scopes what I have owned and used they all have used vector CRT (as normal analog scopes) for it and it was very nice. Just for example 2440 and example 7854 (but 7854 was bit different case with 10-bit digitizer and waveform analyzing processor (with separate keyboard))
Title: Re: True analog scopes
Post by: Mechatrommer on December 16, 2022, 12:57:38 pm
At one time walked then we used horses to pull carts then made cars and then planes....it's called progress and difficult for some to fathom or accept.  ::)
but people can still argue horses dont need gas, not poluting environment,...........
They can and will go hungry.
but their 'gas" is freely available grow on the land, sometime we even have to work to get rid of them. and their "waste" will enrich the land to grow more "gas", its the "naturally designed" recycling technology. you cant win! ;)
Title: Re: True analog scopes
Post by: vk6zgo on December 16, 2022, 02:32:50 pm

\ the usual reasons imho is lack of googling, or hard to get rid old habit

"Googling" doesn't help to get "hands on" experience of modern DSOs.

Yes, you can look up the specs, or the operator's manual (if such exists), or maybe a Youtube video, but none of these match the experience of having the real thing in front of us.

If someone already has a functional Oscilloscope to hand, the much-touted advantages of the "latest & greatest" don't amount to an overwhelming argument for buying a new DSO.
If I had "money to burn", I might start collecting a bunch of new equipment, just so I could experience them at first hand, but sadly, I don't.
Title: Re: True analog scopes
Post by: vk6zgo on December 16, 2022, 02:43:24 pm
Unfortunately I have heard too many people saying they want a digitial scope solely because of the auto-setup button. On further questioning, they actively don't want to learn what's in a scope, nor its pitfalls and traps, nor how to get the best from it.

Micsigs have a mode where they continuously adjust the horizontal/vertical scale to track the input signal - no need to press a button!  :)

It is hard to think of a more annoying feature!

Depends on the implementation. Watch this video at the 12:40 mark before deciding:

https://www.youtube.com/watch?v=i8NkppAvEQI (https://www.youtube.com/watch?v=i8NkppAvEQI)

He leaves it on for most of the video. Just watch...

Having watched the relevant parts, I'm glad to see that it can be turned off, as that is where it would remain if I was using it.
When the input frequency changes, I like to see more or less cycles appear on the display, not rely upon the frequency readout.

I'm sorry, but I just couldn't warm to that iteration of the MicSig, the "joysticks" strike me as silly---either have a touchscreen only or provide the most important functions as rotary controls.
Title: Re: True analog scopes
Post by: Fungus on December 16, 2022, 03:05:44 pm
Having watched the relevant parts, I'm glad to see that it can be turned off, as that is where it would remain if I was using it.
When the input frequency changes, I like to see more or less cycles appear on the display, not rely upon the frequency readout.

OTOH I can imagine somebody poking around a PCB with both hands occupied and this could be really useful.

PS: The old Micsigs have this feature too...
Title: Re: True analog scopes
Post by: BillyO on December 16, 2022, 04:17:14 pm
At one time (we) walked then we used horses to pull carts then made cars and then planes....it's called progress and difficult for some to fathom or accept.  ::)
You are forgetting that horses and walking, especially walking, are indeed still good things today that do not have viable replacements in certain circumstances.  The same is true for analog scopes.
Title: Re: True analog scopes
Post by: BillyO on December 16, 2022, 04:19:07 pm
but people can still argue horses dont need gas ..
They produce plenty enough of their own. :-DD
Title: Re: True analog scopes
Post by: tautech on December 16, 2022, 07:36:59 pm
All ( tens of) HP digital oscilloscopes what I have owned and used as I remember all have raster CRT including also 1GHz 54111D. 
But Tektronix "CRT" digital scopes what I have owned and used they all have used vector CRT (as normal analog scopes) for it and it was very nice. Just for example 2440 and example 7854 (but 7854 was bit different case with 10-bit digitizer and waveform analyzing processor (with separate keyboard))
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?
Title: Re: True analog scopes
Post by: james_s on December 16, 2022, 09:25:58 pm
Also Tektronix and some others. All ( tens of) HP digital oscilloscopes what I have owned and used as I remember all have raster CRT including also 1GHz 54111D. 
But Tektronix "CRT" digital scopes what I have owned and used they all have used vector CRT (as normal analog scopes) for it and it was very nice. Just for example 2440 and example 7854 (but 7854 was bit different case with 10-bit digitizer and waveform analyzing processor (with separate keyboard))

I have several Tek DSOs, a TDS784C that has a raster CRT display, a TDS3014 that has a color LCD, and then several TDS300 and TDS400 scopes that need various things that are all mono raster CRT. I know they made an early DSO with a vector display but I don't think I've ever used one.
Title: Re: True analog scopes
Post by: tggzzz on December 16, 2022, 09:54:53 pm
All ( tens of) HP digital oscilloscopes what I have owned and used as I remember all have raster CRT including also 1GHz 54111D. 
But Tektronix "CRT" digital scopes what I have owned and used they all have used vector CRT (as normal analog scopes) for it and it was very nice. Just for example 2440 and example 7854 (but 7854 was bit different case with 10-bit digitizer and waveform analyzing processor (with separate keyboard))
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

I would recommend they use whatever is available to them.

What scope would you recommend to someone designing the world's fastest scope?

People do face that kind of decision, and using skill plus imagination is required. It is fun and beneficial to develop such an attitude, even when it isn't necessary. Looks extremely good in job interviews :)
Title: Re: True analog scopes
Post by: Mechatrommer on December 17, 2022, 12:30:20 am
What scope would you recommend to someone designing the world's fastest scope?
if i can name one, could you afford it?
Title: Re: True analog scopes
Post by: BillyO on December 17, 2022, 05:37:54 am
What scope would you recommend to someone designing the world's fastest scope?
if i can name one, could you afford it?
You can easily spend the price of a really nice suburban house with acreage and a private lake on an oscilloscope you don't have the means to use.  These scopes require you to design the circuit you are going to test to be testable by the scope.  @100GHz (or thereabouts) the concept of nice little handheld probes with ground clips is out the window.  If the device you want to test has not been specifically designed to be tested by one of these instruments, just go home and watch youtube, or jerk-off, or whatever.  Most of us can't reasonably make use of a 2GHz scope .. or afford one.
Title: Re: True analog scopes
Post by: jonpaul on December 17, 2022, 05:45:24 am
Bonsoir à tous

fastest Tektronix CRT 7104, 1 ghz with 7A29 plug-ins.
https://w140.com/tekwiki/index.php/7104

 Tektronix made CRT, microchannel intensifier plate,distributed deflection plates,
Circa 1970s..1980s, originally for DOE, AEC,

Beautiful machines, but 50 Ohm Zo input, and very basic plug-ins.
I put a Ghz RF gen or Leonard Bodnar 40 ps pulser to see its incredible BW and transient response.  Excellence for very low PRF events or single shot.But a boat anchor, dominates the lab bench, impractical for scopecart.


So, acquired a decade ago with PUins  and original Tektronix service manual,  sadly,  from a silent key estate.  It's is still working  100%, with 7A29  Vs and 7B10, 7B15 H.  Used sparingly as  the MCP CRT has limited life.

Bon journée

Jon

Title: Re: True analog scopes
Post by: H713 on December 17, 2022, 06:14:00 am
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

In both cases, it depends on what you can get. Any scope is better than no scope, and the $400 that a modern Siglent costs is tough for a lot of students to justify. 54600 series HP/Agilent scopes can often be had for ~$100 in this part of the world, and the money saved there is often well-spent on other stuff - signal generators, soldering equipment, parts, etc.

For a new hobbyist that has the money but no experience, it probably makes sense to start with a new digital scope as long as they don't touch the stupid autoset button.
Title: Re: True analog scopes
Post by: tautech on December 17, 2022, 06:43:19 am
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

In both cases, it depends on what you can get.
Are you living in the same world as the rest of us ?
In 2 weeks I can something from anywhere in the world......1 week from China.

It's not about what you can get but instead the best instrument for today's and future use....they are not expensive.
The hobbyist might pick some CRO boat anchor use in their twilight years however to advise the EE's of tomorrow to get one is just downright irresponsible.
Title: Re: True analog scopes
Post by: tggzzz on December 17, 2022, 09:12:41 am
What scope would you recommend to someone designing the world's fastest scope?
if i can name one, could you afford it?
If I was part of the team developing the world's fastest scope, yes the money would be available.
Title: Re: True analog scopes
Post by: tggzzz on December 17, 2022, 09:14:34 am
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

In both cases, it depends on what you can get. Any scope is better than no scope, and the $400 that a modern Siglent costs is tough for a lot of students to justify. 54600 series HP/Agilent scopes can often be had for ~$100 in this part of the world, and the money saved there is often well-spent on other stuff - signal generators, soldering equipment, parts, etc.

Precisely. Spot on.

I am amazed that people continue to ignore those considerations.
Title: Re: True analog scopes
Post by: tggzzz on December 17, 2022, 09:24:33 am
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

In both cases, it depends on what you can get.
Are you living in the same world as the rest of us ?
In 2 weeks I can something from anywhere in the world......1 week from China.

It's not about what you can get but instead the best instrument for today's and future use....they are not expensive.
The hobbyist might pick some CRO boat anchor use in their twilight years however to advise the EE's of tomorrow to get one is just downright irresponsible.

No, it is not irresponsible. I will leave others to comment on whether a Siglent scope salesman is being "responsible" when they say that, or whether there is some other motivation.

One of the best definitions of an engineer is "someone that can do for £1 what any fool can do for £10".

Frequently during a professional career people will have to make do with what's already available because
I've seen all of those, and had to find workarounds.

Might as well get engineers to think creatively from the outset. That's not true for technicians, of course - and vive la différence!
Title: Re: True analog scopes
Post by: robert.rozee on December 17, 2022, 09:27:45 am
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

In both cases, it depends on what you can get.
Are you living in the same world as the rest of us ?
In 2 weeks I can something from anywhere in the world......1 week from China.

It's not about what you can get but instead the best instrument for today's and future use....they are not expensive.
The hobbyist might pick some CRO boat anchor use in their twilight years however to advise the EE's of tomorrow to get one is just downright irresponsible.

NOT wishing to offend anyone, but while YOU may be able to get something from anywhere in the world, and YOU have the financial resources to pay some hundreds of dollars for a DSO, or professional* multimeter, or name-brand soldering station, etc... there are many people in this world who are POOR.

by POOR i mean having just a few dollars to spend on a hobby, who perhaps live in a tin shack, who access the internet via a $10 cellphone. or they may be a youngster whose parent(s) work 12 hour days and have ZERO spare cash to share once the weekly bills have been paid.

most folks on this forum likely are NOT so poor. but some are. and, indeed, most people in the world are. for those folks the "best instrument for today's and future use" is completely out of reach. so they make do with a $5 multimeter (ICL7106 based, manual ranging), a 2nd hand CRO if they are lucky, and whatever soldering device that can be scavenged for a few dollars.


cheers,
rob   :-)


* by "professional multimeter", i mean a good multimeter that is CAT rated, of either workshop or tradesperson grade.
Title: Re: True analog scopes
Post by: jonpaul on December 17, 2022, 11:38:50 am
RE Cheap vintage CRT scopes:

Everything does NOT come from the internet or China!


At Paris flea mkts paid  EU 5 1 ch 10 MHz Hameg, EU 25 2 ch 20 MHz Hameg. (1980s,  , designed in Germany, made in France)

Similar old analog scopes on local FS websites like Craig List in USA or PAP, Le Bon Coin in France. Certainly others exist in every country!

Amateur radio fleas and estate sales are another source of great vintage equipment!

It takes time and work, and persistance...get off your mobile or PC/MAC and physically LOOK AROUND!

Seek and you will find!

Bon Chance!

Jon

Title: Re: True analog scopes
Post by: Mechatrommer on December 17, 2022, 03:29:03 pm
It's not about what you can get but instead the best instrument for today's and future use....they are not expensive.
The hobbyist might pick some CRO boat anchor use in their twilight years however to advise the EE's of tomorrow to get one is just downright irresponsible.
No, it is not irresponsible. I will leave others to comment on whether a Siglent scope salesman is being "responsible" when they say that, or whether there is some other motivation.
he is being responsible, its just he keep suggesting Siglent brand, which is understandable, but narrowing the option a bit. there are many other options/brands like Rigol, Owon, Hantek etc, or even higher end Keysight/R&S etc, but the point is they are the same in the class more modern more usefull less risky DSO, not some boat anchor model...

i have here an old Advantest R3465 SA (still LCD version) that i got because its the cheapest in the market, thats all i can afford as hobbiest, its nearly $1K costed me. its now has some calibration issue that i dont know how to fix, not enough time resource to do finding faulty parts... then i can find much much older CRT version of HP/Tek SA, if its broken some unobtanium parts inside need replacing... who's responsible? you? the people who always like to advice on boat anchor CRT? here please pour in your professional advice if you think being responsible to poor people who want to do more thing with less. https://www.eevblog.com/forum/repair/advantest-r3465-spectrum-analyzer-repair-help-input-attenuator/msg2456370/#msg2456370 (https://www.eevblog.com/forum/repair/advantest-r3465-spectrum-analyzer-repair-help-input-attenuator/msg2456370/#msg2456370)

One of the best definitions of an engineer is "someone that can do for £1 what any fool can do for £10".
..snip...
so tell me what £100 tool (i dont have to ask what £1 tool) + some imagination stretching we can use to build a 10GHz (i dont have to ask 100GHz) scope? talk rhetorical like Aristotle is easy. real engineers give concrete example! ;) cheers.
Title: Re: True analog scopes
Post by: baldurn on December 17, 2022, 04:00:18 pm
NOT wishing to offend anyone, but while YOU may be able to get something from anywhere in the world, and YOU have the financial resources to pay some hundreds of dollars for a DSO, or professional* multimeter, or name-brand soldering station, etc... there are many people in this world who are POOR.

There are those with no money, or wishing to spend no money, that will take whatever they can get for free. Nothing wrong with that. However most will find to get into electronics in any serious way, you will need to spend at least little. For minimum spend and maximum gain I might propose something like Owon HDS242S as a far superior choice over any boat anchor.
Title: Re: True analog scopes
Post by: tautech on December 17, 2022, 06:00:18 pm
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

In both cases, it depends on what you can get.
Are you living in the same world as the rest of us ?
In 2 weeks I can something from anywhere in the world......1 week from China.

It's not about what you can get but instead the best instrument for today's and future use....they are not expensive.
The hobbyist might pick some CRO boat anchor use in their twilight years however to advise the EE's of tomorrow to get one is just downright irresponsible.

No, it is not irresponsible. I will leave others to comment on whether a Siglent scope salesman is being "responsible" when they say that, or whether there is some other motivation.
You really are pitiful tggzzz, play the ball and not the man please.
If I sold any other brand, even the market leaders would you still challenge my views ?

The days for commercial use of CRO's are gone pure and simple and a POV that you may not like but my nearly 10 years in business plainly displays otherwise and the conclusion I'd already arrived at before Siglent offered me NZ distributor.
I am very fortunate to see all levels of the NZ marketplace which unless you stand in my shoes you never will with some customers taking months to scrape enough together to purchase their first decent scope after also traveling down the road I went as a hobbyist with CRO's only to discover the obvious that unreliable old boat anchors are not worth the effort if you have limited time with your projects.....whom on earth needs to have to their fix tools before being able to use them ?

But no, you see a post from me and associate to a brand rather that respect my knowledge from the hard knocks road travelled to get here ..... pitiful.
Title: Re: True analog scopes
Post by: H713 on December 17, 2022, 06:27:34 pm
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

In both cases, it depends on what you can get.
Are you living in the same world as the rest of us ?
In 2 weeks I can something from anywhere in the world......1 week from China.

It's not about what you can get but instead the best instrument for today's and future use....they are not expensive.
The hobbyist might pick some CRO boat anchor use in their twilight years however to advise the EE's of tomorrow to get one is just downright irresponsible.

At absolutely no point did I suggest someone pick up an analog boat anchor instead of a digital oscilloscope, unless you get something for $10 and can't afford better.

And... we do not all all living in the same part of the world. In the United States, one can regularly get older (but not scary old) test equipment for a pittance. I suggested the 54600 series (particularly the 54622D) because there are a lot of them around (that series of scopes sold VERY well in this country), and they can often be had for very little - sometimes free. In much of the US, they can also be found locally, saving on shipping. In my opinion, they are one of the cheaper way to get a decent, usable scope. Maybe not competitive with a new scope, but better than a lot of the budget digital scopes from 10 or 15 years ago.

Furthermore... in the US, EE students are paying between $7000 and $70,000 per semester, and the intensity of the programs means that many (not all, but many) don't have time to work during the semester. For many students (again, not all, but many), $400 is hard to justify.

Title: Re: True analog scopes
Post by: Mechatrommer on December 17, 2022, 06:37:27 pm
do they have enough time repairing? and getting unobtainium parts? or advices on repair from locals? retired person surely have...
Title: Re: True analog scopes
Post by: tautech on December 17, 2022, 06:55:38 pm
do they have enough time repairing? and getting unobtainium parts? or advices on repair from locals? retired person surely have...
Yup, these are the 2 real worlds and few here understand both.
Title: Re: True analog scopes
Post by: tggzzz on December 17, 2022, 07:11:37 pm
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

In both cases, it depends on what you can get.
Are you living in the same world as the rest of us ?
In 2 weeks I can something from anywhere in the world......1 week from China.

It's not about what you can get but instead the best instrument for today's and future use....they are not expensive.
The hobbyist might pick some CRO boat anchor use in their twilight years however to advise the EE's of tomorrow to get one is just downright irresponsible.

No, it is not irresponsible. I will leave others to comment on whether a Siglent scope salesman is being "responsible" when they say that, or whether there is some other motivation.
You really are pitiful tggzzz, play the ball and not the man please.
If I sold any other brand, even the market leaders would you still challenge my views ?

Resorting to ad-hominem attacks instead of addressing the points made is widely regarded as a sign of someone undermining their own case.

Which brand you sell is irrelevant, of course, and your question represents an unsuccessful attempt to deflect the discussion.

Have I touched a sore point? It sure looks like it :)

Quote
The days for commercial use of CRO's are gone pure and simple and a POV that you may not like but my nearly 10 years in business plainly displays otherwise and the conclusion I'd already arrived at before Siglent offered me NZ distributor.
I am very fortunate to see all levels of the NZ marketplace which unless you stand in my shoes you never will with some customers taking months to scrape enough together to purchase their first decent scope after also traveling down the road I went as a hobbyist with CRO's only to discover the obvious that unreliable old boat anchors are not worth the effort if you have limited time with your projects.....whom on earth needs to have to their fix tools before being able to use them ?

But no, you see a post from me and associate to a brand rather that respect my knowledge from the hard knocks road travelled to get here ..... pitiful.

None of those points address the points I made - and which you you chose to snip (https://www.eevblog.com/forum/testgear/true-analog-scopes/msg4586311/#msg4586311) in an attempt to avoid them. Here are the points again, so you can have a second chance to address them...

Frequently during a professional career people will have to make do with what's already available because
I've seen all of those, and had to find workarounds.

Might as well get engineers to think creatively from the outset. That's not true for technicians, of course - and vive la différence!
Title: Re: True analog scopes
Post by: H713 on December 17, 2022, 07:19:15 pm
Certainly the issue of purchasing systems and contracts is a painful reality.

This might come as a shocker to some, but labs that receive state/federal funding (no matter how innadequate that funding is) are somewhat limited in who they can buy from.

In many cases, it's a $2500+ Tektronix or use what already exists. "Free Market Capitalism", right?
Title: Re: True analog scopes
Post by: Mechatrommer on December 17, 2022, 07:37:19 pm
Frequently during a professional career people will have to make do with what's already available because
  • you need it now, not in a month's time
  • money has to be used for other necessary equipment
  • it won't pass the purchase request process
  • it is back at base, not here in the field
  • boss says you don't need it
  • there is nothing that is capable of doing the job
I've seen all of those, and had to find workarounds.

Might as well get engineers to think creatively from the outset. That's not true for technicians, of course - and vive la différence!
if your company cant afford $400 DSO, i suggest find another company because they surely cant make raise to your salary accordingly... i've also encountered such situation during my short time working as practising (profession) eng... but there is difference/limit between working to the limit and asking the impossible... and every workaround has its catches... be it money, space or time... you wont get anything far with $1 tools, let alone going into GHz region, unless you want to work full time as dumpster diver, but again, the catch is... time... one of it... concrete example will prove me wrong... ymmv.
Title: Re: True analog scopes
Post by: BillyO on December 17, 2022, 08:01:24 pm
do they have enough time repairing? and getting unobtainium parts? or advices on repair from locals? retired person surely have...
Yup, these are the 2 real worlds and few here understand both.
It's actually a serious hobby for quite a few people to get older test equipment and fix it up.

As for business, I know a guy in Toronto that has a thriving business fixing up old Hi-Fi equipment and classic guitar amps.  He and his two technicians all have Tek 465 scopes on their benches.  Not a DSO to be seen.

Good enough is usually good enough. :-+
Title: Re: True analog scopes
Post by: tggzzz on December 17, 2022, 08:14:04 pm
Frequently during a professional career people will have to make do with what's already available because
  • you need it now, not in a month's time
  • money has to be used for other necessary equipment
  • it won't pass the purchase request process
  • it is back at base, not here in the field
  • boss says you don't need it
  • there is nothing that is capable of doing the job
I've seen all of those, and had to find workarounds.

Might as well get engineers to think creatively from the outset. That's not true for technicians, of course - and vive la différence!
if your company cant afford $400 DSO, i suggest find another company because they surely cant make raise to your salary accordingly... i've also encountered such situation during my short time working as practising (profession) eng... but there is difference/limit between working to the limit and asking the impossible... and every workaround has its catches... be it money, space or time... you wont get anything far with $1 tools, let alone going into GHz region, unless you want to work full time as dumpster diver, but again, the catch is... time... one of it... concrete example will prove me wrong... ymmv.

I suspect there is a language divide here, because you have missed the point(s).
Title: Re: True analog scopes
Post by: H713 on December 17, 2022, 08:14:42 pm
do they have enough time repairing? and getting unobtainium parts? or advices on repair from locals? retired person surely have...
Yup, these are the 2 real worlds and few here understand both.
It's actually a serious hobby for quite a few people to get older test equipment and fix it up.

As for business, I know a guy in Toronto that has a thriving business fixing up old Hi-Fi equipment and classic guitar amps.  He and his two technicians all have Tek 465 scopes on their benches.  Not a DSO to be seen.

Good enough is usually good enough. :-+

Analog audio is one of the very few spaces where an analog scope still makes sense, and to this day, any time I'm tracing a signal through an amplifier, I reach for my 2235. The way these scopes are laid out, and the way they operate, makes them more efficient for that kind of work. A Tektronix 547 is a VERY good scope for audio work - that says a thing or two about what we are dealing with.

For someone who is ONLY doing audio work, a strong argument could be made to buy a $60 Non-Tektronix analog scope (yes, you can get good, working analog scopes for that price) and put the rest of their budget to an audio analyzer (going to be >$500 for a decent one).

Even I have come to recognize that this is a very unusual situation, and this thinking doesn't translate well at all to other areas of electronics. This is because no DSO can really measure the performance of respectable audio equipment (you need a lot more dynamic range than even the best DSOs can offer), and as long as you can see a 20 MHz parasitic oscillation, the scope is fine. Audio doesn't even come close to pushing oscilloscopes - put the money into an audio analyzer, and you'll be much better off.
Title: Re: True analog scopes
Post by: tautech on December 17, 2022, 09:40:28 pm
do they have enough time repairing? and getting unobtainium parts? or advices on repair from locals? retired person surely have...
Yup, these are the 2 real worlds and few here understand both.
It's actually a serious hobby for quite a few people to get older test equipment and fix it up.

As for business, I know a guy in Toronto that has a thriving business fixing up old Hi-Fi equipment and classic guitar amps.  He and his two technicians all have Tek 465 scopes on their benches.  Not a DSO to be seen.

Good enough is usually good enough. :-+
Yet when I had time for electronics as a hobby and repaired CRO's as part of it they wouldn't do all I needed and after repairing a few Tek DSO's it was obvious which direction to more in and leave all that obsolete technology behind.
Needing to battle on with limited scope capability wasn't in my future and still isn't !
Title: Re: True analog scopes
Post by: Wallace Gasiewicz on December 18, 2022, 12:06:06 am
I still think that analog scopes offer easier use at low frequencies. However I am using an Agilent 5820 500 MHz Digital scope and possibly the newer probably cheaper scopes could have better low freq uses. Maybe they are better than my Agilent in this respect.
I limped into the 21st century with my Agilent purchase, it took a while getting use to it but now I use it almost exclusively. At RF Freq, it far out performs my old Tek and HP scopes.
I have also seen some impressive FFT traces for some of the newer scopes that I am unable to get my Agilent to produce on the screen. I use a Spectrum Analyzer for this.
Also I am unable to get a usable display of a Transistor Curve Tracer, which is a snap on my analog scopes.
Maybe the new scopes are better than most people like me think because people like me are using older digital scopes that can be out performed by lesser brand newer scopes?
Possibly someone can enlighten me about this.

I still think you can get a real good analog scope at a Hamfest for less than $100, I passed a new looking, working 400 MHz Tek scope (with probes and manuals) up for around that price just recently. (because I passed up that deal, I am expecting to be banned from the TEA Thread)
For audio work you can pick up a 10-30 MHz scope for a few bucks.
I am quite cognizant about the potential for needed repairs even if the unit works well when purchased however.
The fancier the old scope is, the more there is that can go bad and the greater the chance that there are unusual parts that cannot be found. The low MHz scopes are quite easy to fix usually.
Title: Re: True analog scopes
Post by: vk6zgo on December 18, 2022, 12:07:25 am
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

In both cases, it depends on what you can get.
Are you living in the same world as the rest of us ?
In 2 weeks I can something from anywhere in the world......1 week from China.

It's not about what you can get but instead the best instrument for today's and future use....they are not expensive.
The hobbyist might pick some CRO boat anchor use in their twilight years however to advise the EE's of tomorrow to get one is just downright irresponsible.

No, it is not irresponsible. I will leave others to comment on whether a Siglent scope salesman is being "responsible" when they say that, or whether there is some other motivation.

One of the best definitions of an engineer is "someone that can do for £1 what any fool can do for £10".

Frequently during a professional career people will have to make do with what's already available because
  • you need it now, not in a month's time
  • money has to be used for other necessary equipment
  • it won't pass the purchase request process
  • it is back at base, not here in the field
  • boss says you don't need it
  • there is nothing that is capable of doing the job
I've seen all of those, and had to find workarounds.

Might as well get engineers to think creatively from the outset. That's not true for technicians, of course - and vive la différence!

Funny, my experience has been the opposite.

Engineers tend to have "tunnel vision"----they decide some particular thing is the problem, & doggedly pursue that, even to the point of redesigning perfectly functional equipment.

Techs have the advantage of working on multiple pieces of equipment from varying manufacturers over time & can often "zero in" on a problem by comparing how manufacturers of various devices do things.

Of course, this is you have real technicians, not the "monkey see, monkey do" trained poor substitutes sadly so common today.
Title: Re: True analog scopes
Post by: vk6zgo on December 18, 2022, 12:19:37 am
Frequently during a professional career people will have to make do with what's already available because
  • you need it now, not in a month's time
  • money has to be used for other necessary equipment
  • it won't pass the purchase request process
  • it is back at base, not here in the field
  • boss says you don't need it
  • there is nothing that is capable of doing the job


I've seen all of those, and had to find workarounds.

Might as well get engineers to think creatively from the outset. That's not true for technicians, of course - and vive la différence!
if your company cant afford $400 DSO, i suggest find another company because they surely cant make raise to your salary accordingly... i've also encountered such situation during my short time working as practising (profession) eng... but there is difference/limit between working to the limit and asking the impossible... and every workaround has its catches... be it money, space or time... you wont get anything far with $1 tools, let alone going into GHz region, unless you want to work full time as dumpster diver, but again, the catch is... time... one of it... concrete example will prove me wrong... ymmv.

It's not logical, but it happens!

One employer I had, who was more rational than many others, would let me change a $1200 27" professional standard Trinitron picture tube, or even a $12000 output tube for a NEC TV Tx on my own authority, but required me to get a $100 "petty cash" purchase authorised.
Title: Re: True analog scopes
Post by: tautech on December 18, 2022, 12:33:11 am
I still think that analog scopes offer easier use at low frequencies.
Please educate us how.  :-//
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 12:46:47 am
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

In both cases, it depends on what you can get.
Are you living in the same world as the rest of us ?
In 2 weeks I can something from anywhere in the world......1 week from China.

It's not about what you can get but instead the best instrument for today's and future use....they are not expensive.
The hobbyist might pick some CRO boat anchor use in their twilight years however to advise the EE's of tomorrow to get one is just downright irresponsible.

No, it is not irresponsible. I will leave others to comment on whether a Siglent scope salesman is being "responsible" when they say that, or whether there is some other motivation.

One of the best definitions of an engineer is "someone that can do for £1 what any fool can do for £10".

Frequently during a professional career people will have to make do with what's already available because
  • you need it now, not in a month's time
  • money has to be used for other necessary equipment
  • it won't pass the purchase request process
  • it is back at base, not here in the field
  • boss says you don't need it
  • there is nothing that is capable of doing the job
I've seen all of those, and had to find workarounds.

Might as well get engineers to think creatively from the outset. That's not true for technicians, of course - and vive la différence!

Funny, my experience has been the opposite.

Engineers tend to have "tunnel vision"----they decide some particular thing is the problem, & doggedly pursue that, even to the point of redesigning perfectly functional equipment.

Techs have the advantage of working on multiple pieces of equipment from varying manufacturers over time & can often "zero in" on a problem by comparing how manufacturers of various devices do things.

I explicitly decided to be a "jack of all trades and master of none" in preference to "world expert in a niche". I've designed low noise analogue electronics, digital, semi-custom, micros, protocols, hard realtime software, soft realtime software, data analysis software. I have avoided databases (except to replace them with something less overweight), and haven't done much RF.

One problem is the same for techs, engineers, accountants, lawyers, clerks etc. Do you have "10 years experience" or "1 years experience repeated 10 times".

Quote
Of course, this is you have real technicians, not the "monkey see, monkey do" trained poor substitutes sadly so common today.

Ditto engineers :(
Title: Re: True analog scopes
Post by: vk6zgo on December 18, 2022, 01:02:09 am
With that vast experience what do you recommend for
1. The hobbyist with little or no scope experience ?
2. The young professional, say the EE student with limited resources ?

In both cases, it depends on what you can get.
Are you living in the same world as the rest of us ?
In 2 weeks I can something from anywhere in the world......1 week from China.

It's not about what you can get but instead the best instrument for today's and future use....they are not expensive.
The hobbyist might pick some CRO boat anchor use in their twilight years however to advise the EE's of tomorrow to get one is just downright irresponsible.

No, it is not irresponsible. I will leave others to comment on whether a Siglent scope salesman is being "responsible" when they say that, or whether there is some other motivation.

One of the best definitions of an engineer is "someone that can do for £1 what any fool can do for £10".

Frequently during a professional career people will have to make do with what's already available because
  • you need it now, not in a month's time
  • money has to be used for other necessary equipment
  • it won't pass the purchase request process
  • it is back at base, not here in the field
  • boss says you don't need it
  • there is nothing that is capable of doing the job
I've seen all of those, and had to find workarounds.

Might as well get engineers to think creatively from the outset. That's not true for technicians, of course - and vive la différence!

Funny, my experience has been the opposite.

Engineers tend to have "tunnel vision"----they decide some particular thing is the problem, & doggedly pursue that, even to the point of redesigning perfectly functional equipment.

Techs have the advantage of working on multiple pieces of equipment from varying manufacturers over time & can often "zero in" on a problem by comparing how manufacturers of various devices do things.

I've designed low noise analogue electronics, digital, semi-custom, micros, protocols, hard realtime software, soft realtime software, data analysis software. I have avoided databases (except to replace them with something less overweight), and haven't done much RF.

One problem is the same for techs, engineers, accountants, lawyers, clerks etc. Do you have "10 years experience" or "1 years experience repeated 10 times".
Maybe I have been fortunate in working during a period in which Electronics Techs have had to learn new technology "on the run", from Tubes to microprocessors & beyond.
The interesting thing is that you can't let yourself forget the "old stuff" because it still exists out there, along with the "latest & greatest", & will come back & "bite you on the bum" if you aren't careful.
We have all worked with the "1 years experience repeated 10 times" people----somehow, they manage to float through life without their "feet of clay" being found out.
I do think they are less common amongst EEs & techs, than in the other groups you mention.
Quote

Quote
Of course, this is you have real technicians, not the "monkey see, monkey do" trained poor substitutes sadly so common today.

Ditto engineers :(
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 10:07:48 am
Maybe I have been fortunate in working during a period in which Electronics Techs have had to learn new technology "on the run", from Tubes to microprocessors & beyond.

Yes and no.

Yes: I'm not sure about the future, but nowadays I would probably choose the life sciences for a career.

No: when I returned to real-time embedded electronics, it was still 8-bit micros programmed in C. No change in 35-40 years :( Well, smaller, faster, cheaper, but that's only a change in degree, not in kind. The main things that have changed are nanopower and ADC/DAC speed/resolution.

No: there was precisely one tech course I ever attended (on AI in the mid-80s). The rest of the time there were no courses since they could only be in the future :)

Was I lucky or fortunate? Yes, but to some extent I made my luck and grasped chances. I explicitly took one of Frank Herbert's concepts to heart:“And always, he fought the temptation to choose a clear, safe course, warning 'That path leads ever down into stagnation.”

Quote
The interesting thing is that you can't let yourself forget the "old stuff" because it still exists out there, along with the "latest & greatest", & will come back & "bite you on the bum" if you aren't careful.

The fundamentals haven't changed, but there is an awful lot of here-today-gone-tomorrow faddish stuff that is best avoided.

Too many people don't distinguish between the two: some hop onto and evangelise every fad (especially in computer languages and frameworks), some refuse to conceive that stuff taught at university is critically important to today's choices.
Title: Re: True analog scopes
Post by: Wallace Gasiewicz on December 18, 2022, 11:58:42 am
Tautec:

When I switch from say, 30 MHx down to 1 KHz, I sometimes do not get a trace until I push the autoscope function.
On an analog scope all I had to do was to change the time base dial.
Not a big deal now that I know what to do.
Title: Re: True analog scopes
Post by: 2N3055 on December 18, 2022, 12:15:19 pm
Tautec:

When I switch from say, 30 MHx down to 1 KHz, I sometimes do not get a trace until I push the autoscope function.
On an analog scope all I had to do was to change the time base dial.
Not a big deal now that I know what to do.

I have no idea why is that. I assure you that modern low cost scopes from Siglent, Rigol and Micsig (or even noname brands) function perfectly and no such problems exist.

This whole topic steered so away from original question.
Title: Re: True analog scopes
Post by: Mechatrommer on December 18, 2022, 12:31:02 pm
When I switch from say, 30 MHx down to 1 KHz, I sometimes do not get a trace until I push the autoscope function.
On an analog scope all I had to do was to change the time base dial.
Not a big deal now that I know what to do.
i suspect you are on "Normal" triggering mode (which is i suspect unavailable in CRO), you can change to "Auto" triggering mode and you still can see a flat horizontal line if signal is too slow. you can rest assured that we still have that time base dial on DSO to do the same...
Title: Re: True analog scopes
Post by: Fungus on December 18, 2022, 12:33:40 pm
When I switch from say, 30 MHx down to 1 KHz, I sometimes do not get a trace until I push the autoscope function.
On an analog scope all I had to do was to change the time base dial.
Not a big deal now that I know what to do.

I have no idea why is that.

Probably the trigger mode. It might be sat there waiting for a trigger.
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 12:45:30 pm
Tautec:

When I switch from say, 30 MHx down to 1 KHz, I sometimes do not get a trace until I push the autoscope function.
On an analog scope all I had to do was to change the time base dial.
Not a big deal now that I know what to do.
...
I have no idea why is that. I assure you that modern low cost scopes from Siglent, Rigol and Micsig (or even noname brands) function perfectly and no such problems exist.
...

Given examples on this forum and elsewhere, "function perfectly" is a bold claim.

Some firmware upgrades trivially fix bugs like "The position of trigger level is wrong after changing the channel’s invert function.", "The reference waveform is wrong after storing the “CH1” wave of
reference and then changing the source of the reference to “D0” then press the channel setting of reference.", "The position of the trigger is wrong in high resolution mode.", "The value of variance measure item is wrong.", "The system crashes when the trigger level is set to 4 times the vertical scale"

Others bugfixes are/were less completely successful, for example where they involved noisy internal (PLL?) clock sources.

Note: I don't own one of the affected types and so have only peripheral knowledge of the topic based on a 30s google search and imperfectly remembered very long threads on this forum. The statements above are not definitive but do serve to raise questions about false expectations.
Title: Re: True analog scopes
Post by: markone on December 18, 2022, 01:21:57 pm
-snip
No: when I returned to real-time embedded electronics, it was still 8-bit micros programmed in C. No change in 35-40 years :( Well, smaller, faster, cheaper, but that's only a change in degree, not in kind. The main things that have changed are nanopower and ADC/DAC speed/resolution.

Which period are you referring to ?

Anyhow, interesting discussion that brings back to mind the transition era from vinyl to CD music listening in late 80s toward 90s (luckily now finished), funny to note that at the end digital compressed music and class D amplification won hands down after billions of discussions about spectral fidelity, 0.001% THD,  jitter and so on.

The only people that I know that still own an analog scope are old hams (age > 60) that never get through the navigation of two levels menu system.
Title: Re: True analog scopes
Post by: vk6zgo on December 18, 2022, 01:29:30 pm
When I switch from say, 30 MHx down to 1 KHz, I sometimes do not get a trace until I push the autoscope function.
On an analog scope all I had to do was to change the time base dial.
Not a big deal now that I know what to do.
i suspect you are on "Normal" triggering mode (which is i suspect unavailable in CRO), you can change to "Auto" triggering mode and you still can see a flat horizontal line if signal is too slow. you can rest assured that we still have that time base dial on DSO to do the same...

CROs have both "Normal" & "Auto" trigger mode.

When I am looking at various points in a DUT, I normally let the 'scope "free run" in Auto.
Using DC coupling, with no vertical input voltage, I will then see a flat line at my selected zero position, .

This allows me to look at DC supply lines, as well as signal levels.
With 1v/div setting, if the line jumps up by around 5 divisions, I'm looking at a +5v supply, & so on.

If I then look at a point carrying signal, I will usually see that signal (unless it is very small), & can then adjust time/div, volts/div & trigger level to give me a stable display.

The early DSOs I played with didn't seem to have an equivalent to "free running", as without an input signal, they would not show a trace----it seems modern ones do.

I thought "roll" might do the trick, but touching the probe on a DC level displayed a transition from zero to that level, complete with contact bounce, (due to my shaky contact with the probe) overshoots, etc., which made it useless.

In most cases, it wasn't worth persevering with it, as there was a quite adequate CRO available.
Title: Re: True analog scopes
Post by: Fungus on December 18, 2022, 01:51:08 pm
CROs have both "Normal" & "Auto" trigger mode.

When I am looking at various points in a DUT, I normally let the 'scope "free run" in Auto.

DSOs have the same, and a few more, eg. Single shot mode where you trigger once and it grabs the signal so you can look at it at in your own time, maybe even zoom in for a closer look... very useful, but CROs don't do it.
Title: Re: True analog scopes
Post by: vk6zgo on December 18, 2022, 02:21:47 pm
CROs have both "Normal" & "Auto" trigger mode.

When I am looking at various points in a DUT, I normally let the 'scope "free run" in Auto.

DSOs have the same, and a few more, eg. Single shot mode where you trigger once and it grabs the signal so you can look at it at in your own time, maybe even zoom in for a closer look... very useful, but CROs don't do it.

Obviously, "single shot" mode is very useful in applications where a non-recurrent signal needs to be examined, but for recurring signals, a decent CRO has dual/delayed timebases where you can "zoom" in on any point on that displayed waveform.
You have to do it then & there, however.

I was actually answering Mechatrommer who questioned whether "normal" triggering mode was available on CROs.

I agreed that maybe Wallace Gasiewicz may have had his DSO on "normal" & it sort of "morphed" into a discussion of a useful method of using the "auto" trigger function for troubleshooting a circuit.

Title: Re: True analog scopes
Post by: BillyO on December 18, 2022, 02:25:45 pm
DSOs have the same, and a few more, eg. Single shot mode where you trigger once and it grabs the signal so you can look at it at in your own time, maybe even zoom in for a closer look... very useful, but CROs don't do it.
Yes they do.  My Tek 465 does.  I also know the 475 and the 485 will too.
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 02:29:39 pm
-snip
No: when I returned to real-time embedded electronics, it was still 8-bit micros programmed in C. No change in 35-40 years :( Well, smaller, faster, cheaper, but that's only a change in degree, not in kind. The main things that have changed are nanopower and ADC/DAC speed/resolution.

Which period are you referring to ?

First period: early 80s to mid 90s.
Second period: 2015 to date.
Example technology: z80 and arduino atmega328 respectively. Yes, there were alternatives during both those periods, but those are sufficient to illustrate my point.

Quote
Anyhow, interesting discussion that brings back to mind the transition era from vinyl to CD music listening in late 80s toward 90s (luckily now finished), funny to note that at the end digital compressed music and class D amplification won hands down after billions of discussions about spectral fidelity, 0.001% THD,  jitter and so on.

CDs very quickly established themselves as being superior to vinyl in all but one respect: sleeve art.

~1984 I remember listening on a high end (not audiophool!) audio system with a friend to http://arsnovaclassic.blogspot.com/2012/09/michala-petri-blockflotenkonzerte.html (http://arsnovaclassic.blogspot.com/2012/09/michala-petri-blockflotenkonzerte.html) on both CD and vinyl. We could tell a slight difference, but not which was which, nor which was better.

Compression needn't be an issue, but too often people compress too much. When my ears were remotely useful I didn't compress MP3 to less than 192kb/s. Compressed video on TVs is all to obvious, particularly where there is a colour gradient across the screen, e.g. underwater.

Quote
The only people that I know that still own an analog scope are old hams (age > 60) that never get through the navigation of two levels menu system.

Hams are a very poor sample set, for several relevant reasons! :)

I am aware of very competent people that own both analogue and digitising scopes. They are aware of each instrument's characteristics and use the appropriate one.

My principal (and principle) objection is to those that state analogue scopes should not be used and that only digitising scopes should be bought. That's wrong for several relevant reasons.
Title: Re: True analog scopes
Post by: vk6zgo on December 18, 2022, 02:33:05 pm
DSOs have the same, and a few more, eg. Single shot mode where you trigger once and it grabs the signal so you can look at it at in your own time, maybe even zoom in for a closer look... very useful, but CROs don't do it.
Yes they do.  My Tek 465 does.  I also know the 475 and the 485 will too.
The 7613 also has it.
I've played around with it, but never really got a lot of sense out of it.
When/if I fix it, I will have to try again.
Title: Re: True analog scopes
Post by: Mechatrommer on December 18, 2022, 02:55:31 pm
CROs have both "Normal" & "Auto" trigger mode.
When I am looking at various points in a DUT, I normally let the 'scope "free run" in Auto.
and probably Wallace Gasiewicz's CRO doesnt have that feature, since from the way he stated, he never see "Normal" triggering effect in his CRO.
Title: Re: True analog scopes
Post by: nfmax on December 18, 2022, 04:01:14 pm
~1984 I remember listening on a high end (not audiophool!) audio system with a friend to http://arsnovaclassic.blogspot.com/2012/09/michala-petri-blockflotenkonzerte.html (http://arsnovaclassic.blogspot.com/2012/09/michala-petri-blockflotenkonzerte.html) on both CD and vinyl. We could tell a slight difference, but not which was which, nor which was better.

Ooh yes, one of my first ever CD purchases! Still sounds great on the ESL63’s…

Meanwhile, back on topic, as a 66 year old greybeard, I still have a couple of CRT analogue oscilloscopes in the cupboard, but they never really get used. The Keysight MSOX3104T does it all, including ‘analogue’ things like audio and XY, only better
Title: Re: True analog scopes
Post by: 2N3055 on December 18, 2022, 04:49:55 pm
Note: I don't own one of the affected types and so have only peripheral knowledge of the topic based on a 30s google search and imperfectly remembered very long threads on this forum. The statements above are not definitive but do serve to raise questions about false expectations.

By your comments it is obvious you have only peripheral knowledge of modern DSO and are passing judgment based on Google searches and opinion of digital scopes more than 25 years old....

You also made quite "modest" claim that you "simply know it all" about this topic of oscilloscopes ("And I know the accurate and correct facts."). Which is quite the statement for a person that apparently misses last 25 years of development in this field.. You might know the accurate facts, but only about analog part of it. You are missing several books worth of knowledge on new stuff. 

To make it funny enough, whenever someone asks me about probing with a scope, I send them to your web site. Your pages about that are awesome resource and very interesting read anybody that uses the scope should know... You did GREAT job there.. Thank you for that, in the name of everybody.

But luddism about DSO, is just that. 
CRTs are dead.
If you like them, good for you.
Anybody that have very little money (not enough for a cheap DSO) and can get a CRT scope for few buck should go with that. Any scope is better than none. But those are exigent circumstances.
DSO are the way to go, if you can.
Title: Re: True analog scopes
Post by: Mechatrommer on December 18, 2022, 05:12:50 pm
~1984 I remember listening on a high end (not audiophool!) audio system with a friend to http://arsnovaclassic.blogspot.com/2012/09/michala-petri-blockflotenkonzerte.html (http://arsnovaclassic.blogspot.com/2012/09/michala-petri-blockflotenkonzerte.html) on both CD and vinyl. We could tell a slight difference, but not which was which, nor which was better.
a very poor sample set, for several relevant reasons! :)

Quote
The only people that I know that still own an analog scope are old hams (age > 60) that never get through the navigation of two levels menu system.
...removed...
I am aware of very competent people that own both analogue and digitising scopes. They are aware of each instrument's characteristics and use the appropriate one.
another very poor sample set, for several relevant reasons! :)

btw... this topic is in my ignore list... sounds familiar...
https://www.eevblog.com/forum/testgear/have-we-all-been-seduced-by-digital-arent-analogue-scope-nicer/ (https://www.eevblog.com/forum/testgear/have-we-all-been-seduced-by-digital-arent-analogue-scope-nicer/)
Title: Re: True analog scopes
Post by: james_s on December 18, 2022, 06:38:10 pm
DSOs have the same, and a few more, eg. Single shot mode where you trigger once and it grabs the signal so you can look at it at in your own time, maybe even zoom in for a closer look... very useful, but CROs don't do it.
Yes they do.  My Tek 465 does.  I also know the 475 and the 485 will too.
The 7613 also has it.
I've played around with it, but never really got a lot of sense out of it.
When/if I fix it, I will have to try again.

Single sweep on an analog scope is only really useful when using a scope camera or with a storage scope, both of which roughly mimic the behavior of a DSO, which as the name describes is another type of storage oscilloscope.
Title: Re: True analog scopes
Post by: TimFox on December 18, 2022, 06:58:36 pm
One obsolete technology for which I have no nostalgia is analog storage oscilloscopes.
I speak from experience with them.
Title: Re: True analog scopes
Post by: tautech on December 18, 2022, 07:01:05 pm
A very relevant and undeniable point relating to this topic is not one A brand manufacturer still produces a CRO, why is that ?


Title: Re: True analog scopes
Post by: james_s on December 18, 2022, 07:22:40 pm
One obsolete technology for which I have no nostalgia is analog storage oscilloscopes.
I speak from experience with them.

I've always thought they were fascinating. If not for the fact that the tubes are prone to failure I'd have looked for one to have in my collection of gear.
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 07:25:35 pm
Note: I don't own one of the affected types and so have only peripheral knowledge of the topic based on a 30s google search and imperfectly remembered very long threads on this forum. The statements above are not definitive but do serve to raise questions about false expectations.

By your comments it is obvious you have only peripheral knowledge of modern DSO and are passing judgment based on Google searches and opinion of digital scopes more than 25 years old....

You also made quite "modest" claim that you "simply know it all" about this topic of oscilloscopes ("And I know the accurate and correct facts."). Which is quite the statement for a person that apparently misses last 25 years of development in this field.. You might know the accurate facts, but only about analog part of it. You are missing several books worth of knowledge on new stuff. 

To make it funny enough, whenever someone asks me about probing with a scope, I send them to your web site. Your pages about that are awesome resource and very interesting read anybody that uses the scope should know... You did GREAT job there.. Thank you for that, in the name of everybody.

But luddism about DSO, is just that. 
CRTs are dead.
If you like them, good for you.
Anybody that have very little money (not enough for a cheap DSO) and can get a CRT scope for few buck should go with that. Any scope is better than none. But those are exigent circumstances.
DSO are the way to go, if you can.

Provide references for your (incorrect) assertions.

Don't create strawman arguments. The context you deliberately snipped demonstrates your entire post is a strawman argument - or that there is a significant issue with English not being your first language. Or I could mention less charitable interpretations...
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 07:28:31 pm
~1984 I remember listening on a high end (not audiophool!) audio system with a friend to http://arsnovaclassic.blogspot.com/2012/09/michala-petri-blockflotenkonzerte.html (http://arsnovaclassic.blogspot.com/2012/09/michala-petri-blockflotenkonzerte.html) on both CD and vinyl. We could tell a slight difference, but not which was which, nor which was better.
a very poor sample set, for several relevant reasons! :)

Quote
The only people that I know that still own an analog scope are old hams (age > 60) that never get through the navigation of two levels menu system.
...removed...
I am aware of very competent people that own both analogue and digitising scopes. They are aware of each instrument's characteristics and use the appropriate one.
another very poor sample set, for several relevant reasons! :)

And what might the two sets of reasons be?
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 07:39:30 pm
One obsolete technology for which I have no nostalgia is analog storage oscilloscopes.
I speak from experience with them.

Agreed. Painful. Capturing one off events always was the USP of digitizing scopes.

Having said that I have come across one that works better han I recall, a Telequipment DM63. But digitizing scopes are still preferable.
Title: Re: True analog scopes
Post by: MarkL on December 18, 2022, 07:40:09 pm
DSOs have the same, and a few more, eg. Single shot mode where you trigger once and it grabs the signal so you can look at it at in your own time, maybe even zoom in for a closer look... very useful, but CROs don't do it.
Yes they do.  My Tek 465 does.  I also know the 475 and the 485 will too.
The 7613 also has it.
I've played around with it, but never really got a lot of sense out of it.
When/if I fix it, I will have to try again.

Single sweep on an analog scope is only really useful when using a scope camera or with a storage scope, both of which roughly mimic the behavior of a DSO, which as the name describes is another type of storage oscilloscope.
In the CRO days, it was often only important to know if a particular event occurred (e.g., "the bad thing happened"), and not particularly what the waveform looked like.  In single sweep, the scope would always indicate if it was waiting or if the trigger happened.  It didn't matter if the event was too fast or non-repetitive to visually capture.

In the simplest scenario, one could be waiting for a particular voltage level, but some of the old analog scopes had fairly sophisticated trigger systems to be able look for a specific event and on multiple channels, and some even had logic word-recognizer inputs to look for a pattern such as on a data bus.
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 07:43:47 pm
A very relevant and undeniable point relating to this topic is not one A brand manufacturer still produces a CRO, why is that ?

Are you confusing the output display technology (cro/lcd) with the input front end technology (analogue/digitising/sampling)?

If so that's a silly mistake.
Title: Re: True analog scopes
Post by: james_s on December 18, 2022, 07:50:39 pm
A very relevant and undeniable point relating to this topic is not one A brand manufacturer still produces a CRO, why is that ?

Are you confusing the output display technology (cro/lcd) with the input front end technology (analogue/digitising/sampling)?

If so that's a silly mistake.

Does it matter? As far as I know, no A brand is producing any sort of CRT based scope, whether analog or digital.

And as I've said before, I am skeptical that any manufacture is still making any type of CRT based scope, unless they are assembling them as needed from components that are stocked. I'm not aware of any factory still producing new CRTs of any type.
Title: Re: True analog scopes
Post by: markone on December 18, 2022, 07:58:49 pm
-snip
No: when I returned to real-time embedded electronics, it was still 8-bit micros programmed in C. No change in 35-40 years :( Well, smaller, faster, cheaper, but that's only a change in degree, not in kind. The main things that have changed are nanopower and ADC/DAC speed/resolution.

Which period are you referring to ?

First period: early 80s to mid 90s.
Second period: 2015 to date.
Example technology: z80 and arduino atmega328 respectively. Yes, there were alternatives during both those periods, but those are sufficient to illustrate my point.

Probably we refer to different things, in my mind real time embedded electronics is something complete different where 32bits ARM (Cortex-M, Cortex-R and so on) dominate the market from 2004 with performance that 8 bits could only dream, Arduino is a toy for children.

I worked a lot with Z80 and 8051 in pure assembly code during the 80s and then in plain C with HC11 during the 90s together some expensive Analog Device expensive DSPs, after that everything changed in a way that probably is not clear to everyone, so i do not understand your statement.

It's enough to say that in the mid 90s to implement a brushless motor vector control with a simple HMI and field bus interface was necessary a DSP, an FPGA plus an 8bit MCU, nowadays its enough a 3-4 USD Cortex-M to do a much better job at sensible lower BOM cost.

To finalize, current tech state of real time embedded real time has nothing to do with 8bit era.
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 08:28:51 pm
-snip
No: when I returned to real-time embedded electronics, it was still 8-bit micros programmed in C. No change in 35-40 years :( Well, smaller, faster, cheaper, but that's only a change in degree, not in kind. The main things that have changed are nanopower and ADC/DAC speed/resolution.

Which period are you referring to ?

First period: early 80s to mid 90s.
Second period: 2015 to date.
Example technology: z80 and arduino atmega328 respectively. Yes, there were alternatives during both those periods, but those are sufficient to illustrate my point.

Probably we refer to different things, in my mind real time embedded electronics is something complete different where 32bits ARM (Cortex-M, Cortex-R and so on) dominate the market from 2004 with performance that 8 bits could only dream, Arduino is a toy for children.

I worked a lot with Z80 and 8051 in pure assembly code during the 80s and then in plain C with HC11 during the 90s together some expensive Analog Device expensive DSPs, after that everything changed in a way that probably is not clear to everyone, so i do not understand your statement.

It's enough to say that in the mid 90s to implement a brushless motor vector control with a simple HMI and field bus interface was necessary a DSP, an FPGA plus an 8bit MCU, nowadays its enough a 3-4 USD Cortex-M to do a much better job at sensible lower BOM cost.

To finalize, current tech state of real time embedded real time has nothing to do with 8bit era.

Progression from 8 to 32 bit is part of *smaller faster cheaper", as is condensing a few PCBs into one chip. There is too little fundamental difference, particularly given the other hardware advances.

Fundamental advances might include formal specification and proof an implementation matches the specification, performance guarantees by design without measurement, multicore and distributed languages.

We need fundamental changes and advances, not incremental fiddles :)
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 08:32:49 pm
~1984 I remember listening on a high end (not audiophool!) audio system with a friend to http://arsnovaclassic.blogspot.com/2012/09/michala-petri-blockflotenkonzerte.html (http://arsnovaclassic.blogspot.com/2012/09/michala-petri-blockflotenkonzerte.html) on both CD and vinyl. We could tell a slight difference, but not which was which, nor which was better.

Ooh yes, one of my first ever CD purchases! Still sounds great on the ESL63’s…

It did sound good, didn't it!

I use the past tense only since my wetware is now a limitation :(
Title: Re: True analog scopes
Post by: tautech on December 18, 2022, 08:38:24 pm
A very relevant and undeniable point relating to this topic is not one A brand manufacturer still produces a CRO, why is that ?

Are you confusing the output display technology (cro/lcd) with the input front end technology (analogue/digitising/sampling)?
::)
All oscilloscopes use analogue inputs.
The modern varieties all use LCD of one sort or another and some variety of sampling.

Your point is ?  :-//
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 08:39:53 pm
A very relevant and undeniable point relating to this topic is not one A brand manufacturer still produces a CRO, why is that ?

Are you confusing the output display technology (cro/lcd) with the input front end technology (analogue/digitising/sampling)?

If so that's a silly mistake.

Does it matter? As far as I know, no A brand is producing any sort of CRT based scope, whether analog or digital.

And as I've said before, I am skeptical that any manufacture is still making any type of CRT based scope, unless they are assembling them as needed from components that are stocked. I'm not aware of any factory still producing new CRTs of any type.

Stupid arguments matter, and should be exposed for what they are.

I expect there are still CRT scopes and other instruments being made. They are an ever diminishing and not very interesting niche.
Title: Re: True analog scopes
Post by: tautech on December 18, 2022, 09:03:18 pm
Also I am unable to get a usable display of a Transistor Curve Tracer, which is a snap on my analog scopes.
You'll find all the guidance you need here:
https://www.eevblog.com/forum/projects/dso-awg-based-curve-tracer/ (https://www.eevblog.com/forum/projects/dso-awg-based-curve-tracer/)

And for the PM you sent:
https://www.eevblog.com/forum/testgear/two-tone-test-with-scope-and-sa/ (https://www.eevblog.com/forum/testgear/two-tone-test-with-scope-and-sa/)
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 09:34:05 pm
A very relevant and undeniable point relating to this topic is not one A brand manufacturer still produces a CRO, why is that ?

Are you confusing the output display technology (cro/lcd) with the input front end technology (analogue/digitising/sampling)?
::)
All oscilloscopes use analogue inputs.
The modern varieties all use LCD of one sort or another and some variety of sampling.

Your point is ?  :-//

Some sampling scopes [1] have the sampler directly connected to the input via resistors, inductors and capacitors. The only active amplifying components in the signal path are after the sampler.

That can give vital advantages, since there is zero overload recovery time - because when the sampling gate isn't open the input is effectively disconnected. For scopes that don't have those characteristics, you may need to get the same characteristics by building your own precision high speed sampling front end; see Jim Williams' justly famous AN47 for details.

Whether or not that sampled input is digitised and displayed on a CRT or LCD is obviously a separate design decision.

[1] two examples are the Tektronix 1S1 and 1S2 plugins; I know of one other and I expect there are more. EDIT: add s1, s2 s3, 7s11, 7s12
Title: Re: True analog scopes
Post by: nctnico on December 18, 2022, 10:07:55 pm
CROs have both "Normal" & "Auto" trigger mode.

When I am looking at various points in a DUT, I normally let the 'scope "free run" in Auto.

DSOs have the same, and a few more, eg. Single shot mode where you trigger once and it grabs the signal so you can look at it at in your own time, maybe even zoom in for a closer look... very useful, but CROs don't do it.
Not true. Storage CROs do exist. These can capture a (slow) waveform and keep it on the display. There just isn't any zooming in/out AFAIK. I have used these 30 years ago.
Title: Re: True analog scopes
Post by: nctnico on December 18, 2022, 10:22:23 pm
Frequently during a professional career people will have to make do with what's already available because
  • you need it now, not in a month's time
  • money has to be used for other necessary equipment
  • it won't pass the purchase request process
  • it is back at base, not here in the field
  • boss says you don't need it
  • there is nothing that is capable of doing the job
I've seen all of those, and had to find workarounds.

Might as well get engineers to think creatively from the outset. That's not true for technicians, of course - and vive la différence!
if your company cant afford $400 DSO, i suggest find another company because they surely cant make raise to your salary accordingly... i've also encountered such situation during my short time working as practising (profession) eng... but there is difference/limit between working to the limit and asking the impossible... and every workaround has its catches... be it money, space or time... you wont get anything far with $1 tools, let alone going into GHz region, unless you want to work full time as dumpster diver, but again, the catch is... time... one of it... concrete example will prove me wrong... ymmv.

I suspect there is a language divide here, because you have missed the point(s).
Mechatrommer got the point just fine and is absolutely right. If your employer can't afford good tools that make you do your job efficiently, then it is time to leave. On several occasions I even brought my own equipment along just to get the job done quickly. I want to make progress with the project at hand and not get stuck in endless tinkering & detours. Like your comment earlier about Rigol & Siglent: too many problems may linger so I won't be so quick to use test equipment from those brands in a professional environment (especially with less experienced engineers around). I've learned my lessons; low purchase price and TCO are not the same number. I'm getting paid to create a new product, not to build and/or debug test equipment.
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 11:04:46 pm
CROs have both "Normal" & "Auto" trigger mode.

When I am looking at various points in a DUT, I normally let the 'scope "free run" in Auto.

DSOs have the same, and a few more, eg. Single shot mode where you trigger once and it grabs the signal so you can look at it at in your own time, maybe even zoom in for a closer look... very useful, but CROs don't do it.
Not true. Storage CROs do exist. These can capture a (slow) waveform and keep it on the display. There just isn't any zooming in/out AFAIK. I have used these 30 years ago.

Some were used to capture fast difficult-to-repeat events, especially when measuring nuclear detonations ;)
Title: Re: True analog scopes
Post by: tggzzz on December 18, 2022, 11:08:41 pm
Frequently during a professional career people will have to make do with what's already available because
  • you need it now, not in a month's time
  • money has to be used for other necessary equipment
  • it won't pass the purchase request process
  • it is back at base, not here in the field
  • boss says you don't need it
  • there is nothing that is capable of doing the job
I've seen all of those, and had to find workarounds.

Might as well get engineers to think creatively from the outset. That's not true for technicians, of course - and vive la différence!
if your company cant afford $400 DSO, i suggest find another company because they surely cant make raise to your salary accordingly... i've also encountered such situation during my short time working as practising (profession) eng... but there is difference/limit between working to the limit and asking the impossible... and every workaround has its catches... be it money, space or time... you wont get anything far with $1 tools, let alone going into GHz region, unless you want to work full time as dumpster diver, but again, the catch is... time... one of it... concrete example will prove me wrong... ymmv.

I suspect there is a language divide here, because you have missed the point(s).
Mechatrommer got the point just fine and is absolutely right. If your employer can't afford good tools that make you do your job efficiently, then it is time to leave. On several occasions I even brought my own equipment along just to get the job done quickly. I want to make progress with the project at hand and not get stuck in endless tinkering & detours. Like your comment earlier about Rigol & Siglent: too many problems may linger so I won't be so quick to use test equipment from those brands in a professional environment (especially with less experienced engineers around). I've learned my lessons; low purchase price and TCO are not the same number. I'm getting paid to create a new product, not to build and/or debug test equipment.

I completely agree with you about it being a "time to leave" flag, but mechatrommer did miss the points I was making.
Title: Re: True analog scopes
Post by: vk6zgo on December 18, 2022, 11:33:46 pm
CROs have both "Normal" & "Auto" trigger mode.
When I am looking at various points in a DUT, I normally let the 'scope "free run" in Auto.
and probably Wallace Gasiewicz's CRO doesnt have that feature, since from the way he stated, he never see "Normal" triggering effect in his CRO.

Very unlikely----I have never seen any CRO which has triggering at all, which doesn't offer both "normal" & "auto".

Very early, & a few later very cheap, 'scopes, had a "timebase" that was normally "free running" & used a "sync" control to "sort of" sync the timebase to the incoming signal.
He could, just possibly have one of those.
Title: Re: True analog scopes
Post by: BillyO on December 19, 2022, 03:06:55 am
Here's a little use case for a CRO.

Just a few minutes ago I had a tiny epiphany about something I'm working on and I just wanted to check a signal.  No precise measurement, just wanted to verify it was there and looked like it should.  I went down to the lab, turned on the Tek 465, got a probe and attached it to the scope then to the DUT, twiddled the vertical and the horizontal, saw what I wanted to see, turned off my scope  and put the probe away.  All in about 1/2 the time it would take the SDS2104XP just to boot.
Title: Re: True analog scopes
Post by: H713 on December 19, 2022, 05:31:56 am
Everyone has a slightly different workflow and slightly different preferences when it comes to tools.

Some engineers, when setting up their lab, have both a DSO and an analog scope on their bench. Some will have multiple of each. Others will have just a DSO.

Some engineers will use a DSO for everything, while others will use an analog scope for some tasks and a digital scope for others. It's all an issue of personal preferences, workflow, bench space, etc.

This is no different from other industries. Some people still like to have a console in their recording studio, others do everything in-the-box. Some woodworkers use planes and chisels extensively, others choose to do everything with power tools. Neither way is "better", just different.

I think we can agree that only having an analog scope is a real limitation these days, but there are still valid reasons to have both - even if those reasons are as dumb as "adding some variety".


Why aren't they still made? Easy. DSOs with LCDs are objectively better for most applications, but more importantly, are far, far cheaper to produce and easier to make into a sexy form factor that is easy to sell. Doesn't mean there aren't valid reasons to use an analog scope, but it does mean that the market for new analog scopes is too small to justify the cost to produce them. CRTs are difficult and expensive to manufacture. I believe that there are some companies still making CRTs for maintaining legacy systems (military, aviation, etc) with long lifecycles, but we're talking very small numbers.
Title: Re: True analog scopes
Post by: Njk on December 19, 2022, 08:26:38 am
To finalize, current tech state of real time embedded real time has nothing to do with 8bit era.
Guys, take it easy. I recalled, when my daughter just graduated from the university (she decided to pursue an engineering career despite my objections), I asked her to pass my exam. Short time before I installed a new electricity meter that has IR interface, and I was interested in getting data from that meter in a high-tech style way. The protocol is not IrDA and not plain IEC 61107 (or how it is called now), it's a vendor-specific combination of the IrDA optical transceiver part with a pulse-based protocol like that used in remote controls.

So I asked her to design a PSK/FSK modem that convert that protocol to UART. To simplify the task, I bought a USB IrDA adapter, removed everything except the IR part and the USB bridge, and installed a cheapest Microchip PIC part between them (very basic 8-bit MCU with internal RC oscillator). She had just to write the "firmware".

For me, it was a simple task as I've done many things like that in late 80s. To show that it's doable, I'd implemented it over a couple of weekends. Worked just fine. BTW, analog scope was successfully used in the process. It's quite a real-time embedded application, isn't it?

Sadly, the exam was spectacularly failed. And the stuff becomes more and more complex over the years. I wonder who eventually will be able to do it with clear understanding of what he/she is doing.
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 09:58:59 am
And the stuff becomes more and more complex over the years. I wonder who eventually will be able to do it with clear understanding of what he/she is doing.

That's an interesting topic.

Certainly I agree with you in that the sheer complexity of modern digital components, languages and libraries and frameworks means learning them is a significant cliff to climb. Too many people don't understand the limitations of their tools and/or don't look any deeper than the sales brochure or top-level description.

How can that be minimised? The best technique is a good education that is focussed on the underlying fundamentals of the topics that will remain valid as technology changes. It is only an exception person that can pick up such concepts solely "on the job"; I've come across one.

In contrast a bad education wastes too much time on the current fads which usually have a half-life of <5 years. Too many people have only a surface understanding of the tools and technology they are using. They can still be useful in many circumstances, but often they don't recognise how much they don't know.

On the other hand, I'm sure people were saying the same things 50 years ago about the technologies in use then. Certainly I remember doing practice maths exam papers from the early 50s, and thinking the questions were bloody hard!
Title: Re: True analog scopes
Post by: nctnico on December 19, 2022, 11:42:52 am
In contrast a bad education wastes too much time on the current fads which usually have a half-life of <5 years. Too many people have only a surface understanding of the tools and technology they are using. They can still be useful in many circumstances, but often they don't recognise how much they don't know.

On the other hand, I'm sure people were saying the same things 50 years ago about the technologies in use then. Certainly I remember doing practice maths exam papers from the early 50s, and thinking the questions were bloody hard!
This is getting off-topic...
Old people do tend to get stuck in the past where 'everything was better'. But I have to agree that the quality of education has dropped significantly. A lot of people can get a bachelor's degree nowadays but only because the bar has been set to 50% to what it was -says- 30 years ago. My youngest son is studying software engineering at a bachelor's degree level. Much to my surprise they don't get any math lessons. When I bring it up he claims he'll just look it up on internet. Then I counter with: how do you know what to look for? I get no answer... I'm not going to claim I remember everything I was told during math lessons (I have two books covering all topics and those are 5cm thick each printed on really thin paper).

I also worked on software written by self-thaught programmers. In one case I asked the guy on how he got to a certain formula (partly implemented using ifs for different input ranges). His answer: I just fudged the numbers until the result looks OK. So I asked: and what if the input data is not what you expect, how to raise an error or make sure to show the result is obviously wrong? The guy answered with a shoulder shrug. FFS  :palm: Needless to say I replaced his crap with a single -continuous- formula that worked.
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 12:16:53 pm
In contrast a bad education wastes too much time on the current fads which usually have a half-life of <5 years. Too many people have only a surface understanding of the tools and technology they are using. They can still be useful in many circumstances, but often they don't recognise how much they don't know.

On the other hand, I'm sure people were saying the same things 50 years ago about the technologies in use then. Certainly I remember doing practice maths exam papers from the early 50s, and thinking the questions were bloody hard!
This is getting off-topic...
Old people do tend to get stuck in the past where 'everything was better'. But I have to agree that the quality of education has dropped significantly. A lot of people can get a bachelor's degree nowadays but only because the bar has been set to 50% to what it was -says- 30 years ago.

Any decent engineer will always be looking for the edge cases, thinking how to remove them, and jumping on any way possible to improve things. I'm frustrated where things haven't improved during my career!

In the UK in the 70s the "top" 8-10% went to university. The others became productive other ways.

Now the "top" 50% go to university. Since people haven't changed significantly in 50 years, if the percentage of 1st class degrees is the same then the boundary must be lower. (And in the UK there is currently angst that too high a proportion of people get 1st class degrees).

One of my heroes was Professor Eric Laithwaite at Imperial College. He used to set exams where one question was easy and sufficient get you a pass mark, several were more challenging and could get you a good degree, and one could not be answered adequately in the time available. He expected his undergraduate engineers to be able to determine which questions to avoid. If they couldn't, they wouldn't make good engineers anyway.

Quote
My youngest son is studying software engineering at a bachelor's degree level. Much to my surprise they don't get any math lessons. When I bring it up he claims he'll just look it up on internet. Then I counter with: how do you know what to look for? I get no answer... I'm not going to claim I remember everything I was told during math lessons (I have two books covering all topics and those are 5cm thick each printed on really thin paper).

Our 2nd year maths course was taught by someone from the maths faculty. When we showed our course notes to a maths student he said it was pretty much his entire year. I've no doubt that they went into it in more depth. The end of year exam rubric was "full marks may be obtained for answers to about six questions" :)


Quote
I also worked on software written by self-thaught programmers. In one case I asked the guy on how he got to a certain formula (partly implemented using ifs for different input ranges). His answer: I just fudged the numbers until the result looks OK. So I asked: and what if the input data is not what you expect, how to raise an error or make sure to show the result is obviously wrong? The guy answered with a shoulder shrug. FFS  :palm: Needless to say I replaced his crap with a single -continuous- formula that worked.

Ah yes. "It passes the unit tests therefore it works" belief. What frightened me was that "they" didn't see the flaw in that argument.
Title: Re: True analog scopes
Post by: Njk on December 19, 2022, 01:32:20 pm
How can that be minimised? The best technique is a good education that is focussed on the underlying fundamentals of the topics that will remain valid as technology changes. It is only an exception person that can pick up such concepts solely "on the job"; I've come across one.
I think it's typical quality vs. quantity problem. Yes, it was always like this. The billions of population does not mean that the percentage of individuals with autonomous surviving skills is now higher than at the pre-history time. Worse, more smart machinery effectively results in more dumb people.

Education is very important but the opportunity to use learned knowledge is decreasing as most people then have to do actually a blue-collar work where little of that knowledge is required.

For instance, previously I was designing my own SMPSs from discrete components, and a computer peripheral controllers with tens of LSI logic chips. Now it's no more needed, now it's actually an integration work that requires much less skills (left an FPGA alone). Later, when USB 2.0 just emerged and I was building a USB device, I wrote all the code from scratch. Now it's difficult to explain the reason because everyone knows that a drivers and libraries for all the classes are available. But it was not always like that and again, now much less level of understanding is required to put all the pre-built stuff together. It's something that is less and less of science and more and more of accounting.

Add to that the amount of "accounting" documents to read. Now it's typical to see a manuals of several thousand pages, not of hundred pages as before. As the speed of digesting an information remains constant, more time is required just to read that bs. You can't effectively master the HW without having to read the docs with due attention. Meanwhile, less and less time is available, because of increasing pressure from the market. I strongly suspect few developers did read that at all, because it's not necessary for a quick and dirty implementation.

Not a good environment for individual's personal skills development. Various "turnkey solutions" that every monkey can use are killing that very efficiently.
Few are lucky, but typically - want an interesting work, enjoy a low income.
Title: Re: True analog scopes
Post by: H713 on December 19, 2022, 01:39:53 pm
Not sure how true this story is (came from a prof who was something of a nut), but it does relate to education.

There was an old Hitachi analog scope in the lab - something really crusty like 20 MHz. Nobody used it, but it was chained to a cart that was more valuable than the scope itself. One student spent some time with an Arduino and two DACs, and when thanksgiving break came, was the last person to leave the lab.

When everyone came back after thanksgiving, there was a dick and balls burned into the CRT.

Suffice it to say, the cart it was sitting on was liberated.
Title: Re: True analog scopes
Post by: Njk on December 19, 2022, 03:11:16 pm
BTW I'd obtained my first scope when I was a high school student. Found it on the local junk yard. It was so big and heavy I was barely able to lift it. With the help of my friend, we moved the treasure to my home. It was of very true analog type, with big CRT, no transistors inside, only the tubes. To my surprise, it was in working condition. I spent more than a year learning how a tube amplifier circuits work and what are the effects from changing the values of res and caps. Excellent learning tool.
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 03:12:50 pm
How can that be minimised? The best technique is a good education that is focussed on the underlying fundamentals of the topics that will remain valid as technology changes. It is only an exception person that can pick up such concepts solely "on the job"; I've come across one.
I think it's typical quality vs. quantity problem. Yes, it was always like this. The billions of population does not mean that the percentage of individuals with autonomous surviving skills is now higher than at the pre-history time. Worse, more smart machinery effectively results in more dumb people.

Who knows, but the best back then were just as relatively inventive as the best now. Classic idiocy is "I don't know how to build pyramids, therefore they didn't, therefore it must have been aliens", and many varieties of that theme

Quote
...
Now it's difficult to explain the reason because everyone knows that a drivers and libraries for all the classes are available. But it was not always like that and again, now much less level of understanding is required to put all the pre-built stuff together.

Problems arise when the libraries are subtly faulty, possibly because the implementer wasn't up to the job or because they didn't document their assumptions about how it should not be used.

Quote
Add to that the amount of "accounting" documents to read. Now it's typical to see a manuals of several thousand pages, not of hundred pages as before. As the speed of digesting an information remains constant, more time is required just to read that bs. You can't effectively master the HW without having to read the docs with due attention. Meanwhile, less and less time is available, because of increasing pressure from the market. I strongly suspect few developers did read that at all, because it's not necessary for a quick and dirty implementation.

I recently had a very pleasant surprise in that regard.

I started to us a novel multi-core processor (up to 4000MIPSX) which is like an FPGA in that it allows hard real-time guarantees to be made without measuring and hoping. The RTOS is to all intents and purposes implemented in hardware.

The language and processor descriptions were notably short and very easy to digest. The subtleties were explained clearly with pseudo-code examples. There were no "here there be dragons" exceptions and errata. All that documentation was <200 pages, and fun to read.

I had zero surprises: everything just worked as expected, first time. The first kick-the-tyres speed tests were up and running within a day of receiving the hardware and firing up the tools. Stunning.

Then I added other things like a front panel and peeked/poked comms over a USB link, and everything continued to work as expected and at the same speed.

Absolutely no unexpected behaviour; everything just "worked as it said on the tin". What more could I want!
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 03:15:36 pm
BTW I'd obtained my first scope when I was a high school student. Found it on the local junk yard. It was so big and heavy I was barely able to lift it. With the help of my friend, we moved the treasure to my home. It was of very true analog type, with big CRT, no transistors inside, only the tubes. To my surprise, it was in working condition. I spent more than a year learning how a tube amplifier circuits work and what are the effects from changing the values of res and caps. Excellent learning tool.

Any working scope is better than no scope. A good engineer will work out how to use whatever tools are available.

Those that say something to the effect that "only the latest tool should be considered" are doing budding engineers a disservice.
Title: Re: True analog scopes
Post by: MegaVolt on December 19, 2022, 03:39:48 pm
I started to us a novel multi-core processor (up to 4000MIPSX) which is like an FPGA in that it allows hard real-time guarantees to be made without measuring and hoping. The RTOS is to all intents and purposes implemented in hardware.
It is very interesting! Can you name him?
Title: Re: True analog scopes
Post by: Njk on December 19, 2022, 03:53:20 pm

Problems arise when the libraries are subtly faulty, possibly because the implementer wasn't up to the job or because they didn't document their assumptions about how it should not be used.
And even more problems when it's actually not an option to don't use the library. Because of one reason or another.

Quote
I started to us a novel multi-core processor (up to 4000MIPSX) which is like an FPGA in that it allows hard real-time guarantees to be made without measuring and hoping. The RTOS is to all intents and purposes implemented in hardware.
Intel 432 project resurrection?


Quote
Absolutely no unexpected behaviour; everything just "worked as it said on the tin". What more could I want!
That looks very suspiciously. Where's it came from? A reasonable question at present times. Perhaps it's designed to phone home on every occasion...
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 04:22:46 pm
I started to us a novel multi-core processor (up to 4000MIPSX) which is like an FPGA in that it allows hard real-time guarantees to be made without measuring and hoping. The RTOS is to all intents and purposes implemented in hardware.
It is very interesting! Can you name him?

Search this forum for my posts on the XMOS xCORE processors running xC.
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 04:29:59 pm

Problems arise when the libraries are subtly faulty, possibly because the implementer wasn't up to the job or because they didn't document their assumptions about how it should not be used.
And even more problems when it's actually not an option to don't use the library. Because of one reason or another.

Urg! Sometimes the best approach is to say "no, not me, get someone else in another company to do it" :) Knowing when to walk away is a key skill - as per Eric Laithwaite's exam questions.

Quote
Quote
I started to us a novel multi-core processor (up to 4000MIPSX) which is like an FPGA in that it allows hard real-time guarantees to be made without measuring and hoping. The RTOS is to all intents and purposes implemented in hardware.
Intel 432 project resurrection?

<deity> no!

Transputer (with a sprinkling of Sun's Niagara T chips) and more modern hardware, Occam/CSP, more pragmatism, and carefully limited objectives. It is hard realtime embedded, not general purpose.

CSP/Occam concepts/constructs are making their way into modern languages, e.g. Rust and Go.
Title: Re: True analog scopes
Post by: Njk on December 19, 2022, 05:09:16 pm
Transputer (with a sprinkling of Sun's Niagara T chips) and more modern hardware, Occam/CSP, more pragmatism, and carefully limited objectives. It is hard realtime embedded, not general purpose.

CSP/Occam concepts/constructs are making their way into modern languages, e.g. Rust and Go.
Interesting. I've a book Transputer Applications, edited by Gordon Harp from Royal Signals and Radar Establishment. It was published in 1989. That time, there was some hype about that. Transputers, Occam2, TDS, etc. I was thinking it's long time over
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 06:06:42 pm
Transputer (with a sprinkling of Sun's Niagara T chips) and more modern hardware, Occam/CSP, more pragmatism, and carefully limited objectives. It is hard realtime embedded, not general purpose.

CSP/Occam concepts/constructs are making their way into modern languages, e.g. Rust and Go.
Interesting. I've a book Transputer Applications, edited by Gordon Harp from Royal Signals and Radar Establishment. It was published in 1989. That time, there was some hype about that. Transputers, Occam2, TDS, etc. I was thinking it's long time over

The concepts have kept reappearing, if you know what you are looking for. Some have appeared in Texas Instruments DSP chips, some in libraries for mainstream languages, etc.

Now that single cores have hit a performance barrier, it is no longer to wait 18 months for performance issues to "disappear". Clearly the future is based around multicore processors, multiple threads, distributed memory, and distributed computing. Unfortunately the languages and concepts that implicitly presume single core computation haven't kept up. Yes, they battle valiantly, adding sticking plaster here and there, and will be around as long a COBOL. But new fundamental concepts are necessary.

The XMOS hardware/software ecosystem has tackled those limitatations and problems head-on without compromise amd without being unnecessarily hobbled by backward compatibility. They aren't sufficient for the future: we need more radical advances. But they do indicate the benefits that can be gained.
Title: Re: True analog scopes
Post by: tautech on December 19, 2022, 07:51:56 pm
Any working scope is better than no scope.
It is however when you need to invest in a working scope one need consider if what's available is a worthy investment. Old stuff is just that, old and nearing the end of that bell curve of reliability where the novice especially isn't well served by some unreliable junk that needs a duplicate to help fix it.
Often that novice, a new Uni student is more focussed on projects and studies rather than need fix some old boat anchor. Here in NZ there is not the resources of old scopes in working condition and why would a budding engineering student even want to use one when at Uni they are to use better, much better.


Quote
Those that say something to the effect that "only the latest tool should be considered" are doing budding engineers a disservice.
Those that haven't experienced modern equipment are excused for their ignorance as no longer is a scope just a scope but a LA, FRA, SA, Protocol analyser, Logger, FG and a remote capture instrument and all in a single small box at a single new instrument cost. One investment = most of an analysis lab.

How can even the experienced engineer not be seduced by all this capability or is it they are still living in another century ? Maybe all this technology in a single box blinds them.  :-//
Title: Re: True analog scopes
Post by: james_s on December 19, 2022, 08:23:44 pm
Those that haven't experienced modern equipment are excused for their ignorance as no longer is a scope just a scope but a LA, FRA, SA, Protocol analyser, Logger, FG and a remote capture instrument and all in a single small box at a single new instrument cost. One investment = most of an analysis lab.

How can even the experienced engineer not be seduced by all this capability or is it they are still living in another century ? Maybe all this technology in a single box blinds them.  :-//

I prefer single purpose standalone instruments in almost every case. I have yet to be impressed with the experience of "Swiss army knife" style test equipment, too often it tries to do everything and ends up doing nothing particularly well.
Title: Re: True analog scopes
Post by: tautech on December 19, 2022, 08:37:52 pm
Those that haven't experienced modern equipment are excused for their ignorance as no longer is a scope just a scope but a LA, FRA, SA, Protocol analyser, Logger, FG and a remote capture instrument and all in a single small box at a single new instrument cost. One investment = most of an analysis lab.

How can even the experienced engineer not be seduced by all this capability or is it they are still living in another century ? Maybe all this technology in a single box blinds them.  :-//

I prefer single purpose standalone instruments in almost every case. I have yet to be impressed with the experience of "Swiss army knife" style test equipment, too often it tries to do everything and ends up doing nothing particularly well.
Agreed, especially when just 10 years back this multi capability was in its infancy and in those days I too thought a scope was just a scope and even instruments of that time were quite basic compared with what you can get for the same price today.
Particularly good performance implies an instrument was designed for specific tasks however the modern instrument with multiple capability is a compromise in design but still does tasks adequately well.
Pick your poison and let that define your budget.
Title: Re: True analog scopes
Post by: mawyatt on December 19, 2022, 08:44:46 pm
Find it interesting that just the mention of the word "scope" in any context, brings out all the repeated opinions, arguments and such  :wtf:

For someone that's planning on expanding their knowledge and creating income based upon such, then a more modern "scope" should be considered, since it's likely not to find older analog scopes in use at established labs, companies and universities.

Of course if it's just for home hobby use and "fooling around" then just about anything should prove useful, however will still stand by what we've said earlier that the wiser choice, even if it stretches one's budget, is a modern DSO.

A couple decades ago, one of the major discussions during presentations for securing large company investments (many $100K) for the university WAMI Labs was the students would be learning on some of the more modern equipment rather than the usual hand-me-downs that university labs had. Since these very students would soon become company engineering employees and need to learn how to use modern lab equipment, these WAMI engineers were initially more valuable since they required less "lab learning" and thus less initial company time/$ investment.

Simply they were a better bargain than ones without this WAMI lab experience, and more likely to get hired.

BTW much of the new lab equipment was donated by HP, Tektronix, R&S, Keithley, Anritsu and others, as they also bought into the program figuring when these "former students" were empowered with purchasing decisions, they would lean towards the equipment OEMs that supported their prior university lab experiences. Needless to say the program was highly successful and quickly copied throughout academia  :-+

Best,
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 08:47:01 pm
Those that haven't experienced modern equipment are excused for their ignorance as no longer is a scope just a scope but a LA, FRA, SA, Protocol analyser, Logger, FG and a remote capture instrument and all in a single small box at a single new instrument cost. One investment = most of an analysis lab.

How can even the experienced engineer not be seduced by all this capability or is it they are still living in another century ? Maybe all this technology in a single box blinds them.  :-//

I prefer single purpose standalone instruments in almost every case. I have yet to be impressed with the experience of "Swiss army knife" style test equipment, too often it tries to do everything and ends up doing nothing particularly well.

Just so.

But it is less of an issue if you are only doing simple "low end" measurements, and/or being a field technician. I've usually been pushing the envelope in a lab, so it hasn't been relevant to me.

When one bit breaks, you have to at least consider junking the lot or going back to having multiple instruments.

You may only be able to configure it to be a single instrument at one time, which can be a problem when you need two instruments simultaneously. Plus there being weird restrictions/interactions about which subset of capabilities can used simultaneously.I

And for beginners multiple instruments increases the size of the learning curve.
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 08:54:51 pm
Find it interesting that just the mention of the word "scope" in any context, brings out all the repeated opinions, arguments and such  :wtf:

For someone that's planning on expanding their knowledge and creating income based upon such, then a more modern "scope" should be considered, since it's likely not to find older analog scopes in use at established labs, companies and universities.

Of course if it's just for home hobby use and "fooling around" then just about anything should prove useful, however will still stand by what we've said earlier that the wiser choice, even if it stretches one's budget, is a modern DSO.

A couple decades ago, one of the major discussions during presentations for securing large company investments (many $100K) for the university WAMI Labs was the students would be learning on some of the more modern equipment rather than the usual hand-me-downs that university labs had. Since these very students would soon become company engineering employees and need to learn how to use modern lab equipment, these WAMI engineers were initially more valuable since they required less "lab learning" and thus less initial company time/$ investment.

Simply they were a better bargain than ones without this WAMI lab experience, and more likely to get hired.

BTW much of the new lab equipment was donated by HP, Tektronix, R&S, Keithley, Anritsu and others, as they also bought into the program figuring when these "former students" were empowered with purchasing decisions, they would lean towards the equipment OEMs that supported their prior university lab experiences. Needless to say the program was highly successful and quickly copied throughout academia  :-+

Best,

I agree with that, have never said or implied therwise, and would emphasise the need to balance the cost of buying learning using equipment against the benefits.

In one example I'm familiar with, a division in a highly competent company spent the equivalent of 50 engineers annual salary on a piece of dev kit, simply to get to market 3 months earlier. Good choice in that case :)
Title: Re: True analog scopes
Post by: tautech on December 19, 2022, 09:02:49 pm
And for beginners multiple instruments increases the size of the learning curve.
Certainly and another argument for having multiple functionality in a single box.

This too requires a learning curve but the wise novice expects this and will purchase equipment with multiple capabilities for them to grow into as their skills and understanding develops.

We regularly have customers at all levels of experience selecting a single piece of equipment with LA, FRA, SA, Protocol analyser, Logger, FG and remote capture instrument capabilities and NOT expecting to fully understand the instrument until their skill develops.

Do you imply they are making foolhardy decisions ?
Title: Re: True analog scopes
Post by: bdunham7 on December 19, 2022, 09:08:04 pm
I prefer single purpose standalone instruments in almost every case. I have yet to be impressed with the experience of "Swiss army knife" style test equipment, too often it tries to do everything and ends up doing nothing particularly well.

So a separate ohmmeter, ammeter, DC voltmeter and AC voltmeter then?   :box:

I think you have to determine what the core function of the device is to see what is appropriate to package with it and what isn't.  A DMM is a DC voltmeter at it's core, so it makes sense to add on current shunts, a current source and an AC converter because those  other instruments as standalones would still need the DC voltmeter function. 

Where the CRO/DSO debate is concerned, I think the two are fundamentally different instruments at their core.  The CRO is a fast chart recorder or vector display depending on the setup while a DSO is a really fast low resolution sampling voltmeter.  It makes no obvious sense to 'add' something like spectrum analysis to a CRO because you'd really only be using the CRT as a display.  But if you have a high-rate sampling device like a DSO, then you can do all sorts of interesting things with the data without adding any hardware and that makes perfect sense to me.
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 09:09:50 pm
And for beginners multiple instruments increases the size of the learning curve.
Certainly and another argument for having multiple functionality in a single box.

This too requires a learning curve but the wise novice expects this and will purchase equipment with multiple capabilities for them to grow into as their skills and understanding develops.

Not really. The same is true however many enclosures are on the bench.

Quote
We regularly have customers at all levels of experience selecting a single piece of equipment with LA, FRA, SA, Protocol analyser, Logger, FG and remote capture instrument capabilities and NOT expecting to fully understand the instrument until their skill develops.

Do you imply they are making foolhardy decisions ?

I wouldn't be so foolhardy as to assume my experiences match your commercial experiences, nor those of your clients.

Nonetheless, the technical points I (and others) make are valid.

There's no need to get so touchy about valid differences of opinion!
Title: Re: True analog scopes
Post by: nctnico on December 19, 2022, 09:24:14 pm
Those that haven't experienced modern equipment are excused for their ignorance as no longer is a scope just a scope but a LA, FRA, SA, Protocol analyser, Logger, FG and a remote capture instrument and all in a single small box at a single new instrument cost. One investment = most of an analysis lab.
No. Not by a long shot. Most of the extra features are handy but cover a limited use case. When I need to do network analysis, I use my network analyser (from 10Hz) because it has all the features that FRA on an oscilloscope lacks. For starters the ability to do an offset calibration. Function generator ditto; you'll end up needing a real function generator quickly and often the extra cost for enabling a function generator on a DSO just isn't worth the money at all.
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 09:27:49 pm
I prefer single purpose standalone instruments in almost every case. I have yet to be impressed with the experience of "Swiss army knife" style test equipment, too often it tries to do everything and ends up doing nothing particularly well.

So a separate ohmmeter, ammeter, DC voltmeter and AC voltmeter then?   :box:

It can be fun to push arguments beyond reasonable boundaries :)

Quote
I think you have to determine what the core function of the device is to see what is appropriate to package with it and what isn't.  A DMM is a DC voltmeter at it's core, so it makes sense to add on current shunts, a current source and an AC converter because those  other instruments as standalones would still need the DC voltmeter function. 

Where the CRO/DSO debate is concerned, I think the two are fundamentally different instruments at their core.  The CRO is a fast chart recorder or vector display depending on the setup while a DSO is a really fast low resolution sampling voltmeter.  It makes no obvious sense to 'add' something like spectrum analysis to a CRO because you'd really only be using the CRT as a display.  But if you have a high-rate sampling device like a DSO, then you can do all sorts of interesting things with the data without adding any hardware and that makes perfect sense to me.


The proposition was to bundle AWGs, digital pattern generators, logic analysers, protocol analysers into one box, which is a little more than that.

 Certainly the bundled logic and protocol analysers I have used are far less capable than dedicated instruments, and are only capable of trivial measurements. But such trivial measurements are ideal for salesmen doing demos, since it would be too difficult to explain the more complex uses cases that engineers have to deal with.

But on the subject of using a scope as a spectrum analyser... With an 8 bit ADC optimised for sampling rate, there will be many spurious artefacts in a non-trivial FFT spectrum that will, um, muddy the picture. I prefer to avoid spurious artefacts whenever possible, since distinguishing them from the signals can be tedious and error prone.
Title: Re: True analog scopes
Post by: james_s on December 19, 2022, 09:28:25 pm
So a separate ohmmeter, ammeter, DC voltmeter and AC voltmeter then?   :box:

I think you have to determine what the core function of the device is to see what is appropriate to package with it and what isn't.  A DMM is a DC voltmeter at it's core, so it makes sense to add on current shunts, a current source and an AC converter because those  other instruments as standalones would still need the DC voltmeter function. 

Where the CRO/DSO debate is concerned, I think the two are fundamentally different instruments at their core.  The CRO is a fast chart recorder or vector display depending on the setup while a DSO is a really fast low resolution sampling voltmeter.  It makes no obvious sense to 'add' something like spectrum analysis to a CRO because you'd really only be using the CRT as a display.  But if you have a high-rate sampling device like a DSO, then you can do all sorts of interesting things with the data without adding any hardware and that makes perfect sense to me.

Obviously not everything should be broken down, a multimeter is a handy multipurpose tool. For some cases it would make sense to have dedicated more specialized instruments for some of the functions.

I'm firmly in the DSO camp and it's nice to have features like spectrum analysis although in practice I rarely use it. I have no interest in function generators and logic analyzers and such in a scope though.
Title: Re: True analog scopes
Post by: tggzzz on December 19, 2022, 09:29:55 pm
Those that haven't experienced modern equipment are excused for their ignorance as no longer is a scope just a scope but a LA, FRA, SA, Protocol analyser, Logger, FG and a remote capture instrument and all in a single small box at a single new instrument cost. One investment = most of an analysis lab.
No. Not by a long shot. The extra features are handy but cover a limited use case. When I need to do network analysis, I use my network analyser (from 10Hz) because it has all the features that FRA on an oscilloscope lacks. For starters the ability to do an offset calibration. Function generator ditto; you'll end up needing a real function generator quickly and often the extra cost for enabling a function generator on a DSO just isn't worth the money at all.

Precisely.

But the all-in-one-box sales demo is undoubtedly seductive to the unwary.
Title: Re: True analog scopes
Post by: H713 on December 20, 2022, 07:42:34 am
One of the problems that modern scopes have, in my mind, is that they try to do everything. That's what can them such a chore to use for normal scope operations, for the same reason that an old cell tower service analyzer is a real chore to use as a spectrum analyzer. It's like Windows - MS throws everything in the kitchen sink, along with lots of buzzwords into their release, and the result is that it is awful at everything.

The idea of adding a logic analyzer to a scope is sound - stuff these days is usually mixed signal anyway. In my experience, however, the screen real estate on most scopes is quite limited, and it ends up being miserable to use.

The FFT on a scope remains a pathetic substitute for a spectrum analyzer. Would you buy a 500 MHz spectrum analyzer with 8 bit dynamic range? Didn't think so. It's a nice feature for interpreting goofy waveforms, and maybe some crude EMI debugging in a pinch, but that's the total extent of its usefulness.

The additional hardware required by a signal generator, however, is considerable. It's a whole new device being added, and there's no good reason for it to be in the same box. It's too frustrating to use two-in-one or five-in-one devices of this nature - ditto for DVMs. If you cram a signal generator into a normal scope envelope, you inevitably make a serious sacrifice. Even if the electrical performance is acceptable, the UI won't be.
Title: Re: True analog scopes
Post by: H713 on December 20, 2022, 08:02:13 am
It is however when you need to invest in a working scope one need consider if what's available is a worthy investment. Old stuff is just that, old and nearing the end of that bell curve of reliability where the novice especially isn't well served by some unreliable junk that needs a duplicate to help fix it.
Often that novice, a new Uni student is more focussed on projects and studies rather than need fix some old boat anchor. Here in NZ there is not the resources of old scopes in working condition and why would a budding engineering student even want to use one when at Uni they are to use better, much better.


What are you doing to these things to make them so unreliable? I'm trying to remember the last time I've witnessed an analog scope fail. Usually the ones that need fixing are the ones that have been worked on to the nth degree by someone that decided to replace every capacitor in sight.

By far the least reliable scopes I've seen are some of the old Rigols (and Rigols with an Agilent sticker on them) that seem to have chronic encoder problems.
Title: Re: True analog scopes
Post by: tautech on December 20, 2022, 09:22:37 am
It is however when you need to invest in a working scope one need consider if what's available is a worthy investment. Old stuff is just that, old and nearing the end of that bell curve of reliability where the novice especially isn't well served by some unreliable junk that needs a duplicate to help fix it.
Often that novice, a new Uni student is more focussed on projects and studies rather than need fix some old boat anchor. Here in NZ there is not the resources of old scopes in working condition and why would a budding engineering student even want to use one when at Uni they are to use better, much better.


What are you doing to these things to make them so unreliable? I'm trying to remember the last time I've witnessed an analog scope fail.
Just using them.
At one time my hobby was repairing and selling scopes, any scope that could be found cheap that preferably had manuals available online or they came with them but schematics was a must !

It first started with an English Telequipment D83 given by my mentor that only required a NTC thermistor for the LV primary side EHT inverter but went onto be somewhat unreliable even though that model were made after Tek had acquired Telequipment and it had such a nice CRT the same as Tek used in their 7603.
Last scope to sell.

After that was a HP1740 that had numerous issues including the common terrible cracked solder joints on the PCB connector plug.  ::)
In the meanwhile I was starting to look at DSO's and saved myself from buying a UNIT DSO but instead a Tek TDS2102B.  :phew:
Had been looking at GW Instek but they were overpriced locally.

The Tek became my main scope allowing for accuracy comparisons after repairs of CRO's of which there were a few more:
Aussie BWD
Tek 500 < Gorillas been inside. Love job for the mentor.
English Bradley < EHT transformer secondary winding open, white silicon potted in ferrite pot core on the first layer.  :phew: Lost just 2 turns so adjusted to spec just fine.

Then a couple of DSO's were scored, an infamous TDS210 with the typical busted input BNC's and the need to check it wasn't a recalled SN#. New BNC's and custom mods for it to never happen again.  :horse:
Later a monochrome 60 MHz TDS1002B IIRC with a dead backlight in which the RC for the backlight push/pull oscillator had lost all its C and was just a few pF's !  :-DD
A 60c TH 330nF cap fixed it for a darn good profit as I'd been given it by an EE friend that couldn't be bothered to fix it and instead brought a new Tek.  ::)
The BWD was also sourced from a tech, a TV tech that obviously didn't know where to start as it came with full manuals and like many old Teks suffered from Tants used too close to their voltage rating.  ::)
Another easy fix.  :)

Lessons learnt were there is some circuitry in CRO's that's under stress particularly within the EHT that can't be ignored and mostly is the cause of a not quite right CRO and due to the elevated voltages and not an area the general EE is comfortable working on. Like it or not, this you just can't escape EHT with CRO design and to some degree with early DSO's too that used CCFL LCD backlight.

With these some years of hands on experience I went looking for competitively priced DSO's in brands that at that time were not represented in NZ and by luck teamed up with Siglent very nearly 10 years ago shortly after which the TDS2012B gave up the ghost in protest.  :-DD
It sits unfixed in a box as penance for letting me down where its failing was convection cooling using a top vented chassis allowing crud to settle on IC pins and our humid climate did the rest......another lesson learnt, you can stick your convection cooled equipment where the sun don't shine !

And some accuse me of insufficient experience.  ::)
Title: Re: True analog scopes
Post by: vk6zgo on December 20, 2022, 11:19:01 am

It first started with an English Telequipment D83 given by my mentor that only required a NTC thermistor for the LV primary side EHT inverter but went onto be somewhat unreliable even though that model were made after Tek had acquired Telequipment and it had such a nice CRT the same as Tek used in their 7603.
Last scope to sell.


A while after Tektronix bought Telequipment, I notice that those Tektronix modules assembled at the old Guernsey factory had a noticeably larger percentage of niggling faults than the ones from Beaverton.
It seems that instead of Telequipment getting better, Tektronix got worse!

This was only for about a year, after which, they seemed OK.

That said, Tek could make crap, as witness the 650 series Picture Monitors.
They were truly dire, although they had some strong competition in that category, with the field containing such merdé as some of the Philips things, or the truly gigantic all vacuum tube PAL colour monitor from Blaupunkt that Telecom Aust bought in the early 1970s.
Title: Re: True analog scopes
Post by: tggzzz on December 20, 2022, 11:32:27 am
And some accuse me of insufficient experience.   ::)

Mirror ::)
Title: Re: True analog scopes
Post by: tggzzz on December 20, 2022, 11:37:29 am
Meanwhile, back on topic, as a 66 year old greybeard, I still have a couple of CRT analogue oscilloscopes in the cupboard, but they never really get used. The Keysight MSOX3104T does it all, including ‘analogue’ things like audio and XY, only better

I looked up the purchase price of that, as can anyone else.

But how much is the household contents insurance for it and does that include "accidental damage"? ::)

If I had one, it would be on my bench too :)
Title: Re: True analog scopes
Post by: BillyO on December 20, 2022, 12:45:14 pm
Meanwhile, back on topic, as a 66 year old greybeard, I still have a couple of CRT analogue oscilloscopes in the cupboard, but they never really get used. The Keysight MSOX3104T does it all, including ‘analogue’ things like audio and XY, only better

I looked up the purchase price of that, as can anyone else.

But how much is the household contents insurance for it and does that include "accidental damage"? ::)

If I had one, it would be on my bench too :)
Yeah, for $23K it better be able to make coffee and clean the floors too.  Can anyone say "ostentatious"?  I have some trouble with that after a couple of glasses of wine.
Title: Re: True analog scopes
Post by: switchabl on December 20, 2022, 01:24:17 pm
Well, at 1 GHz I guess the closest analog equivalent may have been the Tek 7104 (with 7A29, 7B15 and 7B10)? According to TekWiki that had a list price of $44,510 when it was discontinued in 1990 ($97,900 in 2022 USD).
Title: Re: True analog scopes
Post by: BillyO on December 20, 2022, 01:40:48 pm
Well, at 1 GHz I guess the closest analog equivalent may have been the Tek 7104 (with 7A29, 7B15 and 7B10)? According to TekWiki that had a list price of $44,510 when it was discontinued in 1990 ($97,900 in 2022 USD).
How many hobbyists do you imagine had one of these in their basement in 1990?
Title: Re: True analog scopes
Post by: Fungus on December 20, 2022, 02:41:14 pm
I prefer single purpose standalone instruments in almost every case. I have yet to be impressed with the experience of "Swiss army knife" style test equipment, too often it tries to do everything and ends up doing nothing particularly well.

So how much does all that cost? How much bench space do you need?
Title: Re: True analog scopes
Post by: switchabl on December 20, 2022, 02:43:00 pm
Well, at 1 GHz I guess the closest analog equivalent may have been the Tek 7104 (with 7A29, 7B15 and 7B10)? According to TekWiki that had a list price of $44,510 when it was discontinued in 1990 ($97,900 in 2022 USD).
How many hobbyists do you imagine had one of these in their basement in 1990?

Very few, naturally. Just thought that would add some interesting context. (New) GHz scopes are all expensive and used to be a lot more so (even though to my knowledge none of them ever made coffee).

If you don't need that kind of bandwidth, you can get MegaZoom IV scopes, with all their advantages (and disadvantages!), for a lot less.
Title: Re: True analog scopes
Post by: BillyO on December 20, 2022, 03:14:51 pm
If you don't need that kind of bandwidth, you can get MegaZoom IV scopes, with all their advantages (and disadvantages!), for a lot less.
Yeah, even the low cost 1GHz scopes are still ~$7K+.  I'm happy with my $1K scope that give me better than 600MHz.  That extra 400MHz is not worth the extra $6K to me.  Add to that that the $7K 1GHz scopes only come with 500MHz probes.  You need to spend another $4K to get the full speed out of them.  As it is I'm trying to source a couple of 750MHz probes so I can get the best out of the scope I have.  My current probes only go to 500MHz. :palm:
Title: Re: True analog scopes
Post by: tggzzz on December 20, 2022, 04:54:25 pm
Well, at 1 GHz I guess the closest analog equivalent may have been the Tek 7104 (with 7A29, 7B15 and 7B10)? According to TekWiki that had a list price of $44,510 when it was discontinued in 1990 ($97,900 in 2022 USD).

When Tek 465s were current every-lab-has-one scopes (mid-late 70s), they cost around an engineer's annual salary. By that token the Keysight MSOX3104T are relatively cheap.
Title: Re: True analog scopes
Post by: joeqsmith on December 20, 2022, 05:36:20 pm
If you don't need that kind of bandwidth, you can get MegaZoom IV scopes, with all their advantages (and disadvantages!), for a lot less.
Yeah, even the low cost 1GHz scopes are still ~$7K+.  I'm happy with my $1K scope that give me better than 600MHz.  That extra 400MHz is not worth the extra $6K to me.  Add to that that the $7K 1GHz scopes only come with 500MHz probes.  You need to spend another $4K to get the full speed out of them.  As it is I'm trying to source a couple of 750MHz probes so I can get the best out of the scope I have.  My current probes only go to 500MHz. :palm:

Resistive probes are fairly inexpensive and at 1GHz, I would imagine many people will make their own. 

https://www.eevblog.com/forum/testgear/fifty-ohm-probes/ (https://www.eevblog.com/forum/testgear/fifty-ohm-probes/)

For me the choice isn't true analog vs digital, it's used digital vs used digital.  The only way I can afford to play is to lag 10+ years behind.   
Title: Re: True analog scopes
Post by: tautech on December 20, 2022, 06:37:48 pm
Yeah, even the low cost 1GHz scopes are still ~$7K+. 
Correct, officially.  ;)
In reality you can get the same HW in a 500 MHz version for $ 5890 and hack it.
I had one for several years until a customer wanted it earlier this year.

But with still a few days of 2022 left you can get the 500 MHz model on promotion with a free BW upgrade to 1 GHz.
Title: Re: True analog scopes
Post by: adam4521 on December 20, 2022, 09:17:51 pm
I think, to summarise this energetic thread, that ‘true analog scope’ aka CRO has for some time transitioned to heritage technology. If you are a hobbyist, it depends a bit on what form or direction your hobby takes, but for someone learning modern electronics, a DSO is surely the right proposition if you can get one. There are still compromises at the very bottom end, but if you reach for the Rigol/Siglent/Instek/Micsig arena, the machine will be very functional, modern, with warranty protection.

I thought I would make a comment though about the historic significance of the CROs. Everyone who has used one will have cranked the timebase to maximum time, and watched the bright dot process smoothly across at constant speed, left to right, before flicking back and tracking across again.

But now at fast (but not exceptional) timebase of 20ns/div — get your calculator out to check me — the same beam is tracking horizontally at 500000 m/s, a horizontal line speed of more than 300 miles/second! And the thing that remains astounding for me is that it can repeatedly trigger and track the same groove on the screen, with calibrated speed and mm accuracy. Outside of a physics lab, I’m not sure if anything on earth moves that fast!

This humble vacuum tube ‘etch-a-sketch’ enabled us to see and study things in the natural world that were impossible otherwise. It must surely be one of the most significant inventions of the 20th century, shaping our contemporary world, including the world of computers and, of course, making DSOs possible.

So even if CRO is not for electronics any more, the concept, what was achieved with these machines, still worthy of respect. Might help explain why some of us still hang on to them.

Title: Re: True analog scopes
Post by: joeqsmith on December 20, 2022, 10:21:04 pm
5" screen, 10 div, 20ns per div or 200ns to travel 5".  That's 25,000,000 in/sec or 395 miles/sec. 

I suspect my first analog scope was maybe 1MHz at best.  As we got faster scopes,  I found myself turning off the lights to see the trace.  We had phosphor storage and our poloroid cameras which I guess helped.  How many of us were triggering the scope with our custom delayed trigger to sequence though the sweep, collecting all those photos, allowing minutes to expose, then digitizing that..... 

Then again, the first DSO we had was a Tek 7000 maybe mainframe.  From my memory, the downtime was more than the uptime. 

Considering used vs new,  a 500 MHz is $5890.   22 years ago, I bought my LeCroy  7200.   I think I paid $600 back then.  I had to hack in a different hard drive.   To be fair, I have had to repair it a few times over the years.   It still runs today and I fire it up from time to time when making videos.   The analog BW is 4GHz.  For non-repetitive waveforms, it has a 500MHz BW and can sample one channel interlaced at 2Gsps.  It has a fair amount of built in math functions along with TDR measurements. 

Then again I'm talking about a product produced in the late 1980s, and I'm sure the scope you mention would out perform it in many ways. 
Title: Re: True analog scopes
Post by: bdunham7 on December 20, 2022, 10:55:52 pm
But now at fast (but not exceptional) timebase of 20ns/div — get your calculator out to check me — the same beam is tracking horizontally at 500000 m/s, a horizontal line speed of more than 300 miles/second! And the thing that remains astounding for me is that it can repeatedly trigger and track the same groove on the screen, with calibrated speed and mm accuracy. Outside of a physics lab, I’m not sure if anything on earth moves that fast!

Well, it really isn't 'moving', so there's no limit, not even the speed of light.  A Tek 2465B can move the dot (mostly vertically) over 8cm in 700ps.   That's about 71,500 miles per second or ~0.4c.
Title: Re: True analog scopes
Post by: tautech on December 20, 2022, 11:22:03 pm
But now at fast (but not exceptional) timebase of 20ns/div — get your calculator out to check me — the same beam is tracking horizontally at 500000 m/s, a horizontal line speed of more than 300 miles/second! And the thing that remains astounding for me is that it can repeatedly trigger and track the same groove on the screen, with calibrated speed and mm accuracy. Outside of a physics lab, I’m not sure if anything on earth moves that fast!

Well, it really isn't 'moving', so there's no limit, not even the speed of light.  A Tek 2465B can move the dot (mostly vertically) over 8cm in 700ps.   That's about 71,500 miles per second or ~0.4c.
Which without some form of persistence is arguably of no use to anyone.
It only needs be as fast as we can see which for a repetitive waveform gets multiple writes to the display faster than we can observe.
In a DSO we still have Normal and Single to see and capture these fast events.
Title: Re: True analog scopes
Post by: David Hess on December 21, 2022, 06:32:19 am
The Tektronix 7104 can sweep faster than the speed of light, while at the same time being visible with a single sweep.

https://web.archive.org/web/20110926020847/http://www.oregonlive.com/silicon-forest/index.ssf/2011/09/a_tektronix_oscilloscope_that.html (https://web.archive.org/web/20110926020847/http://www.oregonlive.com/silicon-forest/index.ssf/2011/09/a_tektronix_oscilloscope_that.html)
Title: Re: True analog scopes
Post by: Fungus on December 21, 2022, 06:44:11 am
But now at fast (but not exceptional) timebase of 20ns/div — get your calculator out to check me — the same beam is tracking horizontally at 500000 m/s, a horizontal line speed of more than 300 miles/second! And the thing that remains astounding for me is that it can repeatedly trigger and track the same groove on the screen, with calibrated speed and mm accuracy. Outside of a physics lab, I’m not sure if anything on earth moves that fast!

It's like typing a laser pointer to a spinning motor and watching how fast the dot "moves across" a screen a few miles away. It'll be very fast* but it's not a miracle of engineering.

(*) Maybe even faster than the speed of light...!
Title: Re: True analog scopes
Post by: H713 on December 21, 2022, 07:45:21 am
The Tektronix 7104 can sweep faster than the speed of light, while at the same time being visible with a single sweep.

https://web.archive.org/web/20110926020847/http://www.oregonlive.com/silicon-forest/index.ssf/2011/09/a_tektronix_oscilloscope_that.html (https://web.archive.org/web/20110926020847/http://www.oregonlive.com/silicon-forest/index.ssf/2011/09/a_tektronix_oscilloscope_that.html)

But now at fast (but not exceptional) timebase of 20ns/div — get your calculator out to check me — the same beam is tracking horizontally at 500000 m/s, a horizontal line speed of more than 300 miles/second! And the thing that remains astounding for me is that it can repeatedly trigger and track the same groove on the screen, with calibrated speed and mm accuracy. Outside of a physics lab, I’m not sure if anything on earth moves that fast!

It's like typing a laser pointer to a spinning motor and watching how fast the dot "moves across" a screen a few miles away. It'll be very fast* but it's not a miracle of engineering.

(*) Maybe even faster than the speed of light...!


The fact that the beam can scan faster than the speed of light isn't an engineering miracle, but making it happen in at tube that is less than 30 inches long, and having it be readable with the naked eye is. The 7104 CRT (and the 7104 in general) is a true engineering masterpiece.
Title: Re: True analog scopes
Post by: tggzzz on December 21, 2022, 10:13:21 am
The Tektronix 7104 can sweep faster than the speed of light, while at the same time being visible with a single sweep.

Oh, don't spoil tautech's assertion...

Which without some form of persistence is arguably of no use to anyone.

And definitely don't ask him how people with skill and imagination did and can use such equipment to make quite astounding advances.
Title: Re: True analog scopes
Post by: BillyO on December 21, 2022, 01:58:28 pm
Well, it really isn't 'moving', so there's no limit, not even the speed of light.  A Tek 2465B can move the dot (mostly vertically) over 8cm in 700ps.   That's about 71,500 miles per second or ~0.4c.
The electric field is changing, but it it doing so very much further back in the beam where the rate involved is very much lower than the speed of light.
Title: Re: True analog scopes
Post by: Njk on December 21, 2022, 06:37:14 pm
I think, to summarise this energetic thread, that ‘true analog scope’ aka CRO has for some time transitioned to heritage technology.

For those interested in heritage tech. Excellent free books about the USSR scopes (the nomenclature seems comparable to Tek and HP combined). Describes every related design house, lists all (as the authors claims) Soviet designs, and the post-Soviet scopes, up to 2019 I presume.

Now that company is behind the PicoScope brand so the information is from the horse's mouth.

The books are in Russian but there are a lots of images and it's not a paper scan so I think an automation can be used for translation.

https://eltesta.com/publications (https://eltesta.com/publications)
Title: Re: True analog scopes
Post by: tautech on December 21, 2022, 07:31:00 pm
The Tektronix 7104 can sweep faster than the speed of light, while at the same time being visible with a single sweep.

Oh, don't spoil tautech's assertion...

Which without some form of persistence is arguably of no use to anyone.

And definitely don't ask him how people with skill and imagination did and can use such equipment to make quite astounding advances.
With the all limited skill and imagination I could muster some years back I never found an easy way to get a waveform capture that was simple to take and quick to email, one of the primary reasons I assigned CRO's into the past. Even a manually initiated capture was far more advantageous to anything a CRO could provide let alone engaging a Single shot !

Experienced users might discount the need for captures as frivolous but they aren't to the novice as is proven by the numerous captures on this forum of those seeking help to understand what they see.
Here on the blog and some 20+ yrs later collecting screen captures with phones and uploading them is commonplace while substandard to having settings plainly visible on the display.

Those that haven't yet embraced DSO's are also unaware how user focus changes once some muscle memory develops your eyes rarely leave the display as settings are displayed there rather than need to have eyeballs walk around a CRO to arrive at how it was set up.
Title: Re: True analog scopes
Post by: tggzzz on December 21, 2022, 07:38:06 pm
I think, to summarise this energetic thread, that ‘true analog scope’ aka CRO has for some time transitioned to heritage technology.

Many CROs are actually digital/digitising.

(Cathode Rays are part of the output technology, whereas analogue/digitizing is the input technology).

Some Cathode Ray Oscilloscopes are both analogue and digitising, usually called "combiscopes" or similar.

Quote
So even if CRO is not for electronics any more, the concept, what was achieved with these machines, still worthy of respect. Might help explain why some of us still hang on to them.

All technologies have advantages and diaadvantages.

Newer technologies hopefully have advantages over older technologies. That doesn't mean older technologies are useless. Neither does it mean newer technologies don't have disadvantages.

Engineers should be capable of choosing the most appropriate (in a very wide sense) technology no matter what buckshot salesmen and managers utter, and should be able to make the best of whatever is available.
Title: Re: True analog scopes
Post by: tggzzz on December 21, 2022, 07:50:36 pm
The Tektronix 7104 can sweep faster than the speed of light, while at the same time being visible with a single sweep.

Oh, don't spoil tautech's assertion...

Which without some form of persistence is arguably of no use to anyone.

And definitely don't ask him how people with skill and imagination did and can use such equipment to make quite astounding advances.
With the all limited skill and imagination I could muster some years back I never found an easy way to get a waveform capture that was simple to take and quick to email, one of the primary reasons I assigned CRO's into the past.

Wow. What a revealing assertion!

When not in my own lab using my own equipment, a camera is the fastest, simplest, and easiest way to capture a waveform. Imperfect example taken quickly under non-stop circumstances but one where the information has been admired by those interested in more than prettiness:
(https://www.eevblog.com/forum/testgear/show-us-your-square-wave/?action=dlattach;attach=550679/)

Even in my own lab, it is fast and easy!

Or are you unable to use a digital camera and attach a photo to email?! Is that beyond your imagination?!

Title: Re: True analog scopes
Post by: tggzzz on December 21, 2022, 08:04:14 pm
The Tektronix 7104 can sweep faster than the speed of light, while at the same time being visible with a single sweep.

Oh, don't spoil tautech's assertion...

Which without some form of persistence is arguably of no use to anyone.

And definitely don't ask him how people with skill and imagination did and can use such equipment to make quite astounding advances.
Those that haven't yet embraced DSO's are also unaware how user focus changes once some muscle memory develops your eyes rarely leave the display as settings are displayed there rather than need to have eyeballs walk around a CRO to arrive at how it was set up.

Those that have used digitizing scopes in anger for non-trivial measurements know:

It is easier, of course, if you are only selling using one manufacturers scopes. Most of us are using scopes from several manufacturers, each with their own GUI and quirks.

Personally I've only used HP, Tektronix, Digilent, Rigol digitizing scopes. I haven't used the ones you sell, Siglent; maybe they are perfect.
Title: Re: True analog scopes
Post by: H713 on December 22, 2022, 05:19:15 am
Tautech does bring up a solid point, and what is IMO the MAIN reason to use a DSO over an analog scope, and that's the ability to capture single-shot events.

If you're dealing with anything that is pulsed, an analog scope is a PITA. Pulsed systems are all over the place now - power supply startup behavior, communication that happens in response to a user input (button push, etc).

You could use an analog storage scope. You could use a triggered scope camera. I sure wouldn't want to though...

And if you need to change the time base after taking the shot? Out of luck.




Also, let's differentiate between scopes with CRTs and analog scopes. The HP 54600 and Tek TDS380 both have CRTs, but have a lot more in common with a modern Siglent than they do with a Tek 465 or any other analog scope.
Title: Re: True analog scopes
Post by: tautech on December 22, 2022, 07:12:08 am
Tautech does bring up a solid point, and what is IMO the MAIN reason to use a DSO over an analog scope, and that's the ability to capture single-shot events.
Correction, to capture any event !

Greybeards just can't get their heads around this as they already know it all  ::) and never need to put a waveform capture in front of a mentor or here on the forum to seek advice/explanation of what they see.
All the skill and imagination of someone less experienced will never solve something they don't understand until that skill and imagination is gained from experience.
Which raise an old and valid question, which came first the chicken or the egg ?

Quote
If you're dealing with anything that is pulsed, an analog scope is a PITA. Pulsed systems are all over the place now - power supply startup behavior, communication that happens in response to a user input (button push, etc).

You could use an analog storage scope. You could use a triggered scope camera. I sure wouldn't want to though...

And if you need to change the time base after taking the shot? Out of luck.
100%
What today isn't pulsed in one manner or another ?

Quote
Also, let's differentiate between scopes with CRTs and analog scopes. The HP 54600 and Tek TDS380 both have CRTs, but have a lot more in common with a modern Siglent than they do with a Tek 465 or any other analog scope.
No, it's simpler than that as the main basic types of general purpose scope are just 2 types, DSO's or CRO's.
Some older CRO looking scopes are DSO's with a CRT display.

So just 2 main types, boat anchor CRO's with an analogue signal path through to the CRT display or the more capable DSO of which modern ones use LCD displays.
Title: Re: True analog scopes
Post by: tautech on December 22, 2022, 07:43:25 am
The Tektronix 7104 can sweep faster than the speed of light, while at the same time being visible with a single sweep.

Oh, don't spoil tautech's assertion...

Which without some form of persistence is arguably of no use to anyone.

And definitely don't ask him how people with skill and imagination did and can use such equipment to make quite astounding advances.
Those that haven't yet embraced DSO's are also unaware how user focus changes once some muscle memory develops your eyes rarely leave the display as settings are displayed there rather than need to have eyeballs walk around a CRO to arrive at how it was set up.

Those that have used digitizing scopes in anger for non-trivial measurements know:
  • many important settings are not shown on the display
  • the pain of chasing through multilevel menu to find/access a relevant setting
  • settings that are shown are often cryptic and difficult to understand, except by those familiar with the specific scope's display
Skill and imagination resolves all these issues.
Title: Re: True analog scopes
Post by: alm on December 22, 2022, 08:56:45 am
Correction, to capture any event !

For repetitive events, you just take a picture of the screen. Which as tggzzz showed is also often the fastest on a DSO if you don't have connectivity set up beforehand. This technology existed then and it's even easier now.

What today isn't pulsed in one manner or another ?

Oscillators? Power supply ripple? Signals used in analog audio? Most kind of test signals coming from a function gen or pattern gen?

Also, many 'single-shot' events can be made repetitive (excluding destructive tests like nuclear fission tests). Drive the button input using a pulse train. Trigger the reset of a system using a function generator.

I have actually done that with a DSO just because it makes testing changes, like adding a cap, much quicker than manually resetting the test.
Title: Re: True analog scopes
Post by: tautech on December 22, 2022, 10:01:41 am
Correction, to capture any event !

For repetitive events, you just take a picture of the screen. Which as tggzzz showed is also often the fastest on a DSO if you don't have connectivity set up beforehand. This technology existed then and it's even easier now.
That's the thing with only using old equipment, you guys are missing out on so much capability now that memory is so cheap.
Not so much in the sub$1k bracket but many midrange save to internal memory if you don't have a USB stick installed. Then in menus so many seem to despise, within the File manager you can grab those captures remotely or transfer them to a later installed USB stick.
Title: Re: True analog scopes
Post by: tggzzz on December 22, 2022, 10:04:37 am
Tautech does bring up a solid point, and what is IMO the MAIN reason to use a DSO over an analog scope, and that's the ability to capture single-shot events.

If you're dealing with anything that is pulsed, an analog scope is a PITA. Pulsed systems are all over the place now - power supply startup behavior, communication that happens in response to a user input (button push, etc).

You could use an analog storage scope. You could use a triggered scope camera. I sure wouldn't want to though...

And if you need to change the time base after taking the shot? Out of luck.

Fully agreed. One-off events have always been the USP for storage scopes.

Analogue storage scopes always were a PITA, only used because there was nothing better. Early digitising storage scopes capitalised on that pain, even though they were suboptimum for other purposes.

Having said that, with analogue waveforms it is usually possible to make them repetitive. Less so with digital dignals, but you would normally use a logic analyser for those.

Quote
Also, let's differentiate between scopes with CRTs and analog scopes. The HP 54600 and Tek TDS380 both have CRTs, but have a lot more in common with a modern Siglent than they do with a Tek 465 or any other analog scope.

Agreed - again.

I find it sad that people who claim to know a lot about the subject deliberately continue to make that faux pas even after it is pointed out to them.
Title: Re: True analog scopes
Post by: tggzzz on December 22, 2022, 10:15:30 am
Also, let's differentiate between scopes with CRTs and analog scopes. The HP 54600 and Tek TDS380 both have CRTs, but have a lot more in common with a modern Siglent than they do with a Tek 465 or any other analog scope.
No, it's simpler than that as the main basic types of general purpose scope are just 2 types, DSO's or CRO's.
Some older CRO looking scopes are DSO's with a CRT display.

So just 2 main types, boat anchor CRO's with an analogue signal path through to the CRT display or the more capable DSO of which modern ones use LCD displays.

Still confusing the front-end technology with the display technology?! Remarkable and sad.

H713 is right, and IMNSHO insisting otherwise doesn't increase your credibility.
Title: Re: True analog scopes
Post by: tggzzz on December 22, 2022, 10:21:41 am
Correction, to capture any event !

For repetitive events, you just take a picture of the screen. Which as tggzzz showed is also often the fastest on a DSO if you don't have connectivity set up beforehand. This technology existed then and it's even easier now.

What today isn't pulsed in one manner or another ?

Oscillators? Power supply ripple? Signals used in analog audio? Most kind of test signals coming from a function gen or pattern gen?

Also, many 'single-shot' events can be made repetitive (excluding destructive tests like nuclear fission tests). Drive the button input using a pulse train. Trigger the reset of a system using a function generator.

I have actually done that with a DSO just because it makes testing changes, like adding a cap, much quicker than manually resetting the test.

Spot on. Just so. Not difficult, really.

I don't think you'll get tautech to acknowledge that though. He has too much invested in believing otherwise.

(Having said that, I have had to fault-find a power-up problem that required a 6 hour off period for the problem to re-occur. To nobody's surprise a storage scope was highly beneficial in locating the source of that problem :) Right tool for the right job, and all that. )
Title: Re: True analog scopes
Post by: baldurn on December 22, 2022, 05:03:48 pm
Tautech does bring up a solid point, and what is IMO the MAIN reason to use a DSO over an analog scope, and that's the ability to capture single-shot events.

I feel this statement is so very wrong. The MAIN reason to use a DSO is every reason just about. You need to find reasons the other way around: is there still any reason at all to use or own an old analog scope?

One of the reasons stated in this thread is about beginners and poor people. The thing is that beginners absolutely do not want to get stuck with an old boat anchor. In the HAM community some older people do their very best to tell every newcomer that they need that old boat anchor. Luckily they usually fail and the new guy gets something much better. When pressed, this seems to be mostly about the old guys not wanting to learn about DSO or they have experience with some very old DSO that is nothing like a modern DSO.

I take part in a small maker space community with an electronic lab. We do some teaching, usually teaching other members. We do have some old analog scopes on the floor (donated to us) but nobody knows if these things even turn on. Why would we care? We have some Rigols and I recently got an Siglent SDS1104X-E + SDG1032X for the maker space, so we could do bode plots. I am not going to teach the new guy how to operate the boat anchor and then by the way, if you want to do bode plots, or thousand other things, you also need to learn the DSO. That makes no sense at all.

About poor people, in our area I would just recommend them to use our lab for free. Of course we live in a rich country. But for the guy that survives on 1 USD/day in Africa? - he sadly probably is not going to be very concerned about scopes at all. There is a very small pool of people that have enough to have a chance for learning and needing a scope, yet can not afford even a used DSO nor get access to free options. Especially students have options to use the facility of their learning institute with no costs.
Title: Re: True analog scopes
Post by: tggzzz on December 22, 2022, 06:03:54 pm
Tautech does bring up a solid point, and what is IMO the MAIN reason to use a DSO over an analog scope, and that's the ability to capture single-shot events.

I feel this statement is so very wrong. The MAIN reason to use a DSO is every reason just about. You need to find reasons the other way around: is there still any reason at all to use or own an old analog scope?

That is a standard mistake in logical thinking. Just because X implies Y, it does not mean not-X implies not-Y.

In addition, your implication that people are advising not to use digitising scopes is incorrect.

Use a tool that satisfies the requirements. Analogue and digitising scopes are equally good at many important tasks.
Title: Re: True analog scopes
Post by: baldurn on December 22, 2022, 06:20:59 pm

That is a standard mistake in logical thinking. Just because X implies Y, it does not mean not-X implies not-Y.

I am not quite sure what you are trying to say with that. But if we must, the MAIN reason to use a DSO includes:

Single shot capture
Zooming on a captured waveform
Programable triggers of many kinds
Serial decoding
MSO
Statistics displayed on screen
FFT
Network connectivity
Programability by scripting / remote control
Much better display
Auto setup
Multiple acquisition modes
Math modes
Mask tests
Power analyses / other kinds of analyses
Bode plot

The list just continues. There is so much the analog scope can not do. Especially the analog scopes available cheaply.

On the other hand, the MAIN reason to use an analog boat anchor is:

NONE - for most of us.

Other reasons might be:

Analog scopes is the only thing I know and I do not need or wish to learn any of the new stuff
Analog scopes is what I got and I do not wish to spend any money
(Old) Analog scopes is a hoppy

And THAT explains why nobody is producing analog scopes anymore.
Title: Re: True analog scopes
Post by: james_s on December 22, 2022, 06:29:03 pm
Skill and imagination resolves all these issues.

The same is true for analog scopes. I'm firmly in the DSO camp now but we got by for many years with analog scopes, only a select few were lucky enough to have access to a storage scope in the analog era. I remember writing specific code that would cause a microcontroller to do the same thing repeatedly so I could see what was going on on the scope. There are all sorts of tricks people used to get the job done. A DSO is superior now in almost every case, but for decades they did not exist and a lot of the early ones had serious shortfalls. People found ways to get the CRO to show them what they needed to see. It's understandable that people stick to what they know, learning new concepts and skills gets harder for everyone the older we get. If some new whiz bang technology replaces DSOs 40 years from now I think there's a good chance you'll be clinging to your then ancient DSO because it's what you know.
Title: Re: True analog scopes
Post by: james_s on December 22, 2022, 06:33:32 pm
That's the thing with only using old equipment, you guys are missing out on so much capability now that memory is so cheap.
Not so much in the sub$1k bracket but many midrange save to internal memory if you don't have a USB stick installed. Then in menus so many seem to despise, within the File manager you can grab those captures remotely or transfer them to a later installed USB stick.

That's not new. My 25 year old DSO has an internal hard drive that can save and transfer waveforms, screenshots and other data. It was a very expensive high end instrument when new though.
Title: Re: True analog scopes
Post by: BillyO on December 22, 2022, 07:02:57 pm
Tautech does bring up a solid point, and what is IMO the MAIN reason to use a DSO over an analog scope, and that's the ability to capture single-shot events.
Well, I'm not sure this is quite true.  I and others that have posted on this thread have noted that many better CROs can do single sweep triggering.  I used to use that feature all the time and long before DSOs were ever dreamed of.  Sure the DSO alleviates the need for a camera, but the feature is not something that came about with the advent of the DSO.

Y'all need to quit using this as the main reason to have a DSO.  It's not.
Title: Re: True analog scopes
Post by: tggzzz on December 22, 2022, 07:35:56 pm

That is a standard mistake in logical thinking. Just because X implies Y, it does not mean not-X implies not-Y.

I am not quite sure what you are trying to say with that. But if we must, the MAIN reason to use a DSO includes:

Your list with my response...
Single shot capture The USP for storage scopes; agreed
Zooming on a captured waveform Analogue scopes have delayed trigger. (Some digitising scopes cannot zoom - useless!)
Programable triggers of many kinds I've found those to be good when playing around, but insufficient for normal jobs
Serial decoding Digital domain tools are much better: protocol analysers and printf(). Some digitising scopes only decode what's on the screen, which is useless
MSO Scope plus logic/protocol analyser is usually sufficient. Where not, there's a fair chance a digitising scope won't be either
Statistics displayed on screen Some analogue scopes display some stats on screen. While digitising scopes appear to have more complex stats, their accuracy in the context of the specific waveform has to be verified. Too many scope's firmware has been found to have subtle bugs
FFT 8bit ADCs are limited toys w.r.t. FFTs. 14bit is much better, and even then it would be better to use a sound card for audio or dedicated spectrum analyser for RF. Some digitising scopes only do an FFT of what's on the screen, which is useless
Network connectivity In most cases a convenient feature rather than a sigificant benefit
Programability by scripting / remote control I don't know how you can usefully script looking at an analogue waveform to find something unexpected. For digital signals use a digital domain tool:  a decent logic analyser or protocol analyser will have far superior triggering and filtering
Much better display Analogue displays are usually sufficient for analogue waveforms. For digital domain analysis, a digitising scope's screen quickly becomes a limiting factor; better to use the better triggering/filtering in a logic/protocol analyser, or offline post-processing in a computer
Auto setup Ah, the "I don't know how to work it / I don't know what I'm expecting to see" button beloved of those that like the "Tesla full self-driving (beta)" way of using an instrument :)
Multiple acquisition modes, Math modes I've never found those necessary, but provided an 8bit ADC isn't a limitation then it could be an advantage
Mask tests useful for production tests, less so for exploratory design
Power analyses / other kinds of analyses I use a DMM or the relevant special tool for those
Bode plot Severely limited by 8bit DACs, not just a simple digitising scope, can be achieved other ways

Quote
The list just continues. There is so much the analog scope can not do. Especially the analog scopes available cheaply.

The cheap digitising scopes are severely limited; they look enticing, but are disappointing when you look in detail.

Your other points are strawman arguments addressed previously.

Quote
And THAT explains why nobody is producing analog scopes anymore.

No. The main reason is economic: it is now far cheaper to make a new digitising scope than a new analogue scope.

Good old analogue scopes are far cheaper than decent new digitising scopes.
Title: Re: True analog scopes
Post by: james_s on December 22, 2022, 07:55:13 pm
Y'all need to quit using this as the main reason to have a DSO.  It's not.

It's the main reason I use a DSO. Yes it's possible to do single sweep with a CRO and a camera, but that's a big pain. Doing a single shot capture on a DSO is trivial, it's the biggest advantage that the average user will see the most benefit in. They other perks they offer are nice too, but single sweep is the big one.
Title: Re: True analog scopes
Post by: tggzzz on December 22, 2022, 09:13:53 pm
Y'all need to quit using this as the main reason to have a DSO.  It's not.

It's the main reason I use a DSO. Yes it's possible to do single sweep with a CRO and a camera, but that's a big pain. Doing a single shot capture on a DSO is trivial, it's the biggest advantage that the average user will see the most benefit in. They other perks they offer are nice too, but single sweep is the big one.

... Single sweep with the displayed waveform retained by more than the phosphors' persistence :)

Even so, it is somewhat surprising how useful that can be, if that's all you've got :)
Title: Re: True analog scopes
Post by: TimFox on December 22, 2022, 09:16:59 pm
An especially useful feature of DSOs is the ability to display the waveform in a single sweep before the triggering event.
Title: Re: True analog scopes
Post by: tggzzz on December 22, 2022, 09:21:02 pm
An especially useful feature of DSOs is the ability to display the waveform in a single sweep before the triggering event.

Agreed, that's something which the unlamented analogue storage scopes couldn't do.

It is less compelling with repetitive waveforms, of course.
Title: Re: True analog scopes
Post by: mag_therm on December 22, 2022, 09:42:44 pm
ARRR..., But we had the original Hioki Hi-Corders, 4 channel, they could capture sub microsecond.
I forget how much pre-trigger but quite a lot, seconds even.
The chart paper would be spread across the engineering office floor so everybody could offer their learned opinion.
Title: Re: True analog scopes
Post by: baldurn on December 22, 2022, 10:16:39 pm

Your list with my response...
Single shot capture The USP for storage scopes; agreed
Zooming on a captured waveform Analogue scopes have delayed trigger. (Some digitising scopes cannot zoom - useless!)

This is just so much easier on the DSO. Delayed trigger also does not exactly do the same thing. Segmented capture? Searching for events matching a pattern? Dual view of zoomed out and zoomed in view?

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Programable triggers of many kinds I've found those to be good when playing around, but insufficient for normal jobs

There is just stuff you can not do without. Runt triggering for example is not easy or impossible on many analog scopes. Means you are simply not going to get the job done. Or that you have do something contrived and complex instead of something easy on the DSO.

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Serial decoding Digital domain tools are much better: protocol analysers and printf(). Some digitising scopes only decode what's on the screen, which is useless
MSO Scope plus logic/protocol analyser is usually sufficient. Where not, there's a fair chance a digitising scope won't be either

You can always get more (digital!) instruments but the point is that the modern DSO is very versatile. It will usually do the job. It might not be the best for every job, nothing is. It is a function the analog scope simply does not do (again).

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Statistics displayed on screen Some analogue scopes display some stats on screen. While digitising scopes appear to have more complex stats, their accuracy in the context of the specific waveform has to be verified. Too many scope's firmware has been found to have subtle bugs

There is no comparison. The old cheap analog scopes do not display any stats at all (only more advanced expensive ones do). Talking about bugs in firmware is just handwaving. The stats a very useful. Not because you can't do without but because it is so easy and its just there. No need to calculate something yourself when the machine does it.

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FFT 8bit ADCs are limited toys w.r.t. FFTs. 14bit is much better, and even then it would be better to use a sound card for audio or dedicated spectrum analyser for RF. Some digitising scopes only do an FFT of what's on the screen, which is useless

I just compared FFT on my new Siglent SDS2104X HD with my spectrum analyzer. It was damn impressive. But even with the cheaper entry level scope SDS1104X-E you get 1 Mpts FFT which will help the average HAM operator to verify his transmitter just fine. I also find it very useful for teaching.

Could you use a sound card? Possibly but when you are done spending the day setting that up, the guy with a DSO just pressed a few buttons on his DSO to the job done. Not to mention that the sound card is yet another digital solution, it is limited to audio frequencies and usually requires additional hardware anyway.

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Network connectivity In most cases a convenient feature rather than a sigificant benefit
Programability by scripting / remote control I don't know how you can usefully script looking at an analogue waveform to find something unexpected.

Not useless just because you have no need for networking. There has to be a reason that all modern instruments come with it. What might it be?

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For digital signals use a digital domain tool:  a decent logic analyser or protocol analyser will have far superior triggering and filtering[/b]

Again the DSO is a versatile tool. It might not be the best but it can do a lot of stuff for free. Even the entry level scopes have this stuff. And sometimes it is just important to have the analog and digital signals on the same screen - nothing does that better than the DSO. The analog scopes does not do it at all.

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Much better display Analogue displays are usually sufficient for analogue waveforms. For digital domain analysis, a digitising scope's screen quickly becomes a limiting factor; better to use the better triggering/filtering in a logic/protocol analyser, or offline post-processing in a computer

"sufficient" does not equal "good". Lets just admit that the small CRTs are horrible and that the new breed of entry level scopes with 10 inch touch screens are just so nice that you would think it came straight from Startrek... are there uses where an even bigger screen is better? Of course, that is why all new DSO are network connected so you can bring that right to your huge 30 inch desktop.

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Auto setup Ah, the "I don't know how to work it / I don't know what I'm expecting to see" button beloved of those that like the "Tesla full self-driving (beta)" way of using an instrument :)

That is right. Beginners love that button. Sure sometimes they love it too much. Someone here claimed the analog scope is so easy because every lever is visible and right there. Well tell you what - the beginner just presses that one hated button and usually he gets what he wants. Not sure why it should be hated when its helps people.

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Multiple acquisition modes, Math modes I've never found those necessary, but provided an 8bit ADC isn't a limitation then it could be an advantage
Mask tests useful for production tests, less so for exploratory design
Power analyses / other kinds of analyses I use a DMM or the relevant special tool for those
Bode plot Severely limited by 8bit DACs, not just a simple digitising scope, can be achieved other ways

That is pure rubbish. Bode plot is _very_ useful. It seems to be doing the job excellently for most purposes and 8 bit does not matter at all. Again the versatile tool DSO does it, but is not the only instrument or maybe the best instrument, but why should that take anything away if it solves the job?  Never seen an analog scope that could do bode plot.

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The list just continues. There is so much the analog scope can not do. Especially the analog scopes available cheaply.

The cheap digitising scopes are severely limited; they look enticing, but are disappointing when you look in detail.

Your other points are strawman arguments addressed previously.

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And THAT explains why nobody is producing analog scopes anymore.

No. The main reason is economic: it is now far cheaper to make a new digitising scope than a new analogue scope.

Good old analogue scopes are far cheaper than decent new digitising scopes.

The new entry level DSOs from Siglent and Rigol et al are fantastic devices. You are not going to find an analog scope + something that replaces all of what the DSO also does for anything less. That would be true even if the analog scope was free which is why everyone ends up with a DSO in the end.
Title: Re: True analog scopes
Post by: David Hess on December 22, 2022, 10:52:11 pm
I just compared FFT on my new Siglent SDS2104X HD with my spectrum analyzer. It was damn impressive. But even with the cheaper entry level scope SDS1104X-E you get 1 Mpts FFT which will help the average HAM operator to verify his transmitter just fine. I also find it very useful for teaching.

The reason I am never impressed with DSO FFTs is that they always lack the basic functionality of a true spectrum analyzer, like a noise marker and correction for RBW.  These things would be trivial to add, but for whatever reason DSO designers decline to do so.  My favorite mistake is when they allow averaging with FFTs, and then proceed to average the input to the FFT instead of the output.  And then we get to throwing away the phase results.

A 20 year old DSO with FFT is better than most DSO FFTs today.  Back then they didn't know to leave stuff out.

Title: Re: True analog scopes
Post by: alm on December 22, 2022, 10:56:57 pm
Never seen an analog scope that could do bode plot.
Any sweep function generator with any half-way decent scope with a second channel or external trigger input can do it: EEVblog #396 - Bode Plotting on Your Osciloscope (https://www.youtube.com/watch?v=uMH2hGvqhlE)

For more bandwidth you could use an RF sweeper and an RF diode detector probe.

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The new entry level DSOs from Siglent and Rigol et al are fantastic devices. You are not going to find an analog scope + something that replaces all of what the DSO also does for anything less. That would be true even if the analog scope was free which is why everyone ends up with a DSO in the end.
The Analog Discovery probably comes the closest, and can be bought a lot cheaper than decent entry-level DSOs during sales or on the used market. It contains a DSO, but not a very good one. It is quite nice for bode plotting and FFT due to its 14 bit resolution.

I think few people will argue that a modern DSO isn't much better than most analog scopes for at least 99% of use cases. But an analog scope is still infinitely better than not having a scope, and can still do a lot of useful work. Unless you have a financial interest in selling DSOs, then obviously it's a lost sale either way. In some economies, analog scopes might be available cheaply, while entry level DSOs may not be affordable.

A 20 year old DSO with FFT is better than most DSO FFTs today.  Back then they didn't know to leave stuff out.
Lecroy used to be decent with this (showing phase, math on math, etc). Have they removed it from their more recent models?
Title: Re: True analog scopes
Post by: BillyO on December 22, 2022, 11:01:49 pm
.. they always lack the basic functionality of a true spectrum analyzer, like a noise marker and correction for RBW.  These things would be trivial to add, but for whatever reason DSO designers decline to do so.
Well if they did, how would they convince you to buy their spectrum analyzer?
Title: Re: True analog scopes
Post by: BillyO on December 22, 2022, 11:21:30 pm
Never seen an analog scope that could do bode plot.
How do you think they were done in 1976?

I'd use my scope and an S-100 computer system running CP/M and wrote my own BASIC program to crunch the numbers and print the graphs.

DSOs are great, but we got by just fine without them.  We designed and built aircraft, spaceships, cars, particle accelerators, stereos, TVs, F1 cars, Lamborghini's, satellites, radio transceivers, X-ray machines, CT-scanners,  computers, etc.. 

We also wrote real software in C and assembler that ran word processors, spreadsheets, and engineering applications on 8-bit computer with 65,536 bytes of memory.

Today we have DSOs and people writing buggy, bloated slow as f**k code that requires a million times the processor power and memory to do essentially the same thing.  We're now just learning again how to put men on the moon.

Progress.

Don't get me wrong, I love me DSOs - all 4 of them, but rather than wait a minute for them to boot and then spend another 2 minutes getting lost in badly written menu systems, when I have to have a look at something right now, I usually head for my old Tek 465.
Title: Re: True analog scopes
Post by: baldurn on December 22, 2022, 11:23:10 pm
Any sweep function generator with any half-way decent scope with a second channel or external trigger input can do it:

I can tell you that trick is nothing like the real thing.
Title: Re: True analog scopes
Post by: tggzzz on December 23, 2022, 12:49:48 am
Overall your points have some validity, but most don't stand up to detailed examination. Using strawman arguments doesn't help your contentions.


Your list with my response...
Single shot capture The USP for storage scopes; agreed
Zooming on a captured waveform Analogue scopes have delayed trigger. (Some digitising scopes cannot zoom - useless!)

This is just so much easier on the DSO. Delayed trigger also does not exactly do the same thing. Segmented capture? Searching for events matching a pattern? Dual view of zoomed out and zoomed in view?

Of course it isn't the same thing. Nonetheless the many of the advantages can be obtained by using analogue scopes with digital domain tools. In most cases the digitising scopes triggering filtering and searching digital domain information is worse that the alternative.

Use the right tools for the job; a jack-of-all-trades tool is often poorer than the combination of appropriate tools.

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Programable triggers of many kinds I've found those to be good when playing around, but insufficient for normal jobs

There is just stuff you can not do without. Runt triggering for example is not easy or impossible on many analog scopes. Means you are simply not going to get the job done. Or that you have do something contrived and complex instead of something easy on the DSO.

Runt pulses are part of ensuring signal integrity, and a scope is the right tool for that. Once signal integrity is assured, flip to debugging in the digital domain with logic/protocol analysers.

It is possible, with skill, to use an LA to trigger on runt pulses.
It is often possible to create the conditions under which runt pulses are repetitive, and therefore not requiring storage scopes.

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Serial decoding Digital domain tools are much better: protocol analysers and printf(). Some digitising scopes only decode what's on the screen, which is useless
MSO Scope plus logic/protocol analyser is usually sufficient. Where not, there's a fair chance a digitising scope won't be either

You can always get more (digital!) instruments but the point is that the modern DSO is very versatile. It will usually do the job. It might not be the best for every job, nothing is. It is a function the analog scope simply does not do (again).

I disagree that a DSOs "versatility" means it can usually do the job. It may be able to do your jobs, especially if they are relatively undemanding. My professional experience is littered with cases where tools ran into a brick wall and other tools had to be used instead. Often I had to create a my own custom tool for the job at hand. Using combinations of tools is standard operating procedure. But then I suppose if all you have is a digitising scope, then everything "looks like a nail".

"Swiss army knife" tools (i.e. tools with a principal purpose and other things added) tend to be substandard in all but their principal purpose.

I prefer to use the best tools for any given job.

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Statistics displayed on screen Some analogue scopes display some stats on screen. While digitising scopes appear to have more complex stats, their accuracy in the context of the specific waveform has to be verified. Too many scope's firmware has been found to have subtle bugs

There is no comparison. The old cheap analog scopes do not display any stats at all (only more advanced expensive ones do). Talking about bugs in firmware is just handwaving. The stats a very useful. Not because you can't do without but because it is so easy and its just there. No need to calculate something yourself when the machine does it.

Strawman argument; nobody claimed grotty analogue scopes displayed stats.

The "old advanced expensive" ones are often cheaper than most modern digitising scopes. To take one example, a fully working 345MHz Tek 2465 or 485 costs £300-£450. What does a new >350MHz digitising scope cost?

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FFT 8bit ADCs are limited toys w.r.t. FFTs. 14bit is much better, and even then it would be better to use a sound card for audio or dedicated spectrum analyser for RF. Some digitising scopes only do an FFT of what's on the screen, which is useless

I just compared FFT on my new Siglent SDS2104X HD with my spectrum analyzer. It was damn impressive. But even with the cheaper entry level scope SDS1104X-E you get 1 Mpts FFT which will help the average HAM operator to verify his transmitter just fine. I also find it very useful for teaching.

Including noise floor, intermod products, phase noise, harmonics and other spurii? I doubt it.

See David Hess' points about RBW etc.

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Could you use a sound card? Possibly but when you are done spending the day setting that up, the guy with a DSO just pressed a few buttons on his DSO to the job done. Not to mention that the sound card is yet another digital solution, it is limited to audio frequencies and usually requires additional hardware anyway.

None of that invalidates my statement, and I don't understand what point you are trying to make.

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Network connectivity In most cases a convenient feature rather than a sigificant benefit
Programability by scripting / remote control I don't know how you can usefully script looking at an analogue waveform to find something unexpected.

Not useless just because you have no need for networking. There has to be a reason that all modern instruments come with it. What might it be?

Ah, youngsters. I wonder how long it will be before you understand how marketing works (hint: checkbox specifications)

How, exactly, do you use scripting as described with analogue waveforms? I don't think scripting is as useful as you imagine (production tests excepted).

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For digital signals use a digital domain tool:  a decent logic analyser or protocol analyser will have far superior triggering and filtering[/b]

Again the DSO is a versatile tool. It might not be the best but it can do a lot of stuff for free. Even the entry level scopes have this stuff. And sometimes it is just important to have the analog and digital signals on the same screen - nothing does that better than the DSO. The analog scopes does not do it at all.

Unconvincing argument.

Often there simply isn't space to have all the signals on the screen simultaneously. Combinations of tools ameliorate that by using "complex" filtering and triggering to not display irrelevant data.

Analogy (in the nowledge that all analogies are dangerous!): I use a car to travel on roads and ships to travel on water. An amphibious car would "do it all", but it would not be the best choice.

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Much better display Analogue displays are usually sufficient for analogue waveforms. For digital domain analysis, a digitising scope's screen quickly becomes a limiting factor; better to use the better triggering/filtering in a logic/protocol analyser, or offline post-processing in a computer

"sufficient" does not equal "good". Lets just admit that the small CRTs are horrible and that the new breed of entry level scopes with 10 inch touch screens are just so nice that you would think it came straight from Startrek... are there uses where an even bigger screen is better? Of course, that is why all new DSO are network connected so you can bring that right to your huge 30 inch desktop.

... and let's just admit that a scope's screen isn't up to the job of displaying lots of complex digital signals, whereas a logic or protocol analyser's superior triggering and filtering will remove the unimportant stuff and allow you to concentrate on the useful stuff.

You use the "DSOs may not be good but they are sufficient" argument elsewhere. "Physician, heal thyself".

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Auto setup Ah, the "I don't know how to work it / I don't know what I'm expecting to see" button beloved of those that like the "Tesla full self-driving (beta)" way of using an instrument :)

That is right. Beginners love that button. Sure sometimes they love it too much. Someone here claimed the analog scope is so easy because every lever is visible and right there. Well tell you what - the beginner just presses that one hated button and usually he gets what he wants. Not sure why it should be hated when its helps people.

Too often it gives them what they ask for, but they haven't asked the right question.
Too often it gives them what they ask for, but they don't understand the limitations of the answer.
Too often it gives them what they want, not what they need.
Too often it discourages sanity checking and/or verifying the validity of a result.

There is no substitute for thought and understanding.
In the case of "full self driving (beta)" there is no subsitute for being awake and actively monitoring the vehicle's actions.

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Multiple acquisition modes, Math modes I've never found those necessary, but provided an 8bit ADC isn't a limitation then it could be an advantage
Mask tests useful for production tests, less so for exploratory design
Power analyses / other kinds of analyses I use a DMM or the relevant special tool for those
Bode plot Severely limited by 8bit DACs, not just a simple digitising scope, can be achieved other ways

That is pure rubbish. Bode plot is _very_ useful. It seems to be doing the job excellently for most purposes and 8 bit does not matter at all.

That first sentence is yet another strawman argument; unimpressive.

The 8bits can be a killer, e.g. when assessing filter stop-band performance behaviour.

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Again the versatile tool DSO does it, but is not the only instrument or maybe the best instrument, but why should that take anything away if it solves the job?  Never seen an analog scope that could do bode plot.

See examples in other people's posts, and stop using strawman arguments.

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The list just continues. There is so much the analog scope can not do. Especially the analog scopes available cheaply.

The cheap digitising scopes are severely limited; they look enticing, but are disappointing when you look in detail.

Your other points are strawman arguments addressed previously.

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And THAT explains why nobody is producing analog scopes anymore.

No. The main reason is economic: it is now far cheaper to make a new digitising scope than a new analogue scope.

Good old analogue scopes are far cheaper than decent new digitising scopes.

The new entry level DSOs from Siglent and Rigol et al are fantastic devices. You are not going to find an analog scope + something that replaces all of what the DSO also does for anything less. That would be true even if the analog scope was free which is why everyone ends up with a DSO in the end.

Strawman arguments and non-sequiteurs. Unimpressive.
Title: Re: True analog scopes
Post by: tggzzz on December 23, 2022, 12:58:10 am
The new entry level DSOs from Siglent and Rigol et al are fantastic devices. You are not going to find an analog scope + something that replaces all of what the DSO also does for anything less. That would be true even if the analog scope was free which is why everyone ends up with a DSO in the end.
The Analog Discovery probably comes the closest, and can be bought a lot cheaper than decent entry-level DSOs during sales or on the used market. It contains a DSO, but not a very good one. It is quite nice for bode plotting and FFT due to its 14 bit resolution.

I currently have two Digilent Analogue Discoveries, like them and wheel them out when I need their capabilities. (Must sell one of them :) )

The 14-bit ADC/DAC was a key benefit making me think they are worthwhile. 8bits was, um, uninticing.

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I think few people will argue that a modern DSO isn't much better than most analog scopes for at least 99% of use cases. But an analog scope is still infinitely better than not having a scope, and can still do a lot of useful work. Unless you have a financial interest in selling DSOs, then obviously it's a lost sale either way. In some economies, analog scopes might be available cheaply, while entry level DSOs may not be affordable.

That's pretty much my position, but I would significantly reduce that 99% figure because I use combinations of tools. I have more than a hammer in my toolbox :)
Title: Re: True analog scopes
Post by: tggzzz on December 23, 2022, 01:03:50 am
Never seen an analog scope that could do bode plot.
How do you think they were done in 1976?

I'd use my scope and an S-100 computer system running CP/M and wrote my own BASIC program to crunch the numbers and print the graphs.

DSOs are great, but we got by just fine without them.  We designed and built aircraft, spaceships, cars, particle accelerators, stereos, TVs, F1 cars, Lamborghini's, satellites, radio transceivers, X-ray machines, CT-scanners,  computers, etc.. 

We also wrote real software in C and assembler that ran word processors, spreadsheets, and engineering applications on 8-bit computer with 65,536 bytes of memory.

Today we have DSOs and people writing buggy, bloated slow as f**k code that requires a million times the processor power and memory to do essentially the same thing.  We're now just learning again how to put men on the moon.

Progress.

Don't get me wrong, I love me DSOs - all 4 of them, but rather than wait a minute for them to boot and then spend another 2 minutes getting lost in badly written menu systems, when I have to have a look at something right now, I usually head for my old Tek 465.

Just so.

Except I prefer 2465 and 485 to a 465 :)

Too many youngsters fall into the trap of "I don't know how to build pyramids, therefore they didn't know how to build pyramids (hence aliens must have done it)".
Title: Re: True analog scopes
Post by: tggzzz on December 23, 2022, 01:06:24 am
Any sweep function generator with any half-way decent scope with a second channel or external trigger input can do it:

I can tell you that trick is nothing like the real thing.

Ditto using a digitising scope alone, vs a scope plus logic/protocol analysers and printf() statements.

Physician, heal thyself.
Title: Re: True analog scopes
Post by: BillyO on December 23, 2022, 01:17:38 am
Except I prefer 2465 and 485 to a 465 :)
As would I if I had either.

Too many youngsters fall into the trap of "I don't know how to build pyramids, therefore they didn't know how to build pyramids (hence aliens must have done it)".
Yep, and there is a growing (or is that groaning?) number of them that think the earth is flat.  :palm:

Heaven forbid they solve an engineering approach for themselves instead of pouting that their scope won't do it for them.

Anything to be anti-boomer.
Title: Re: True analog scopes
Post by: tautech on December 23, 2022, 02:24:22 am
Love to stop and chat but too darn busy with a Xmas rush selling these infernal modern DSO's....higher priced ones too !
Title: Re: True analog scopes
Post by: vk6zgo on December 23, 2022, 02:26:54 am
An especially useful feature of DSOs is the ability to display the waveform in a single sweep before the triggering event.

Agreed, that's something which the unlamented analogue storage scopes couldn't do.

It is less compelling with repetitive waveforms, of course.

Analog 'scopes with delay lines can display the waveform in a recurrent waveform before the trigger event, although it is seldom essential.
Title: Re: True analog scopes
Post by: vk6zgo on December 23, 2022, 03:20:38 am
Any sweep function generator with any half-way decent scope with a second channel or external trigger input can do it:

I can tell you that trick is nothing like the real thing.
When I learnt about "Bode plots", it was done by plotting transfer functions on graph paper.
This would give unrealistically sharp corner frequencies.
They were normally done for amplitude and phase response.

When we measured amplitude-v-frequency response of real devices, we used a RF or audio sweeper & an oscilloscope, or an "all in one" sweeper like a Polyskop SWOB.

We called it what it was----a "amplitude/frequency response test".

Back the day, VNAs were "rare as hen's teeth" so we didn't normally have the occasion to do "phase/frequency" testing.

Do the common modern DSOs perform both of these types of test?
Title: Re: True analog scopes
Post by: TimFox on December 23, 2022, 03:45:33 am
An especially useful feature of DSOs is the ability to display the waveform in a single sweep before the triggering event.

Agreed, that's something which the unlamented analogue storage scopes couldn't do.

It is less compelling with repetitive waveforms, of course.

Analog 'scopes with delay lines can display the waveform in a recurrent waveform before the trigger event, although it is seldom essential.

Analog scopes with delay lines allowed the time at the trigger event to be displayed, but very, very little before it.
Title: Re: True analog scopes
Post by: BillyO on December 23, 2022, 04:01:04 am
Love to stop and chat but too darn busy with a Xmas rush selling these infernal modern DSO's....higher priced ones too !
That's all there is to sell .. that's what gets sold.

But, as said before, I love my DSOs.  They will always be my go-to for serious work.  No argument.  But I'm not tossing my CRO anytime soon.

I'm willing to admit that my reflexes are better habituated to a (Tektronix) CRO, but that's what I learned on and spent most of my career as an ET with.  That said, the advantages of a modern DSO are seductive for sure.  And if I have something more serious to do, that's where I go.  However, if the moment calls for a reflexive quick peek at an event or waveform I can best leverage a 40YO Tek to get the job done.  Both technologies have a place in my life.

I can also do the timing and adjust the points, synchronize the carbs and prep the plugs on my '74 RD350.  Many here would be at a total loss and never be able to enjoy the feel of riding an untamed, raw twin cylinder 2-stoke bike of epic reputation.  I pity those that cannot appreciate where they, or their world, came from.

Let me lay out a question.  My Tek 465 has outlived it's era by ~30Y+ but still provides purpose and usefulness.  Can I expect my "improved" SDS2104XP to do the same?  My 12YO UNI-T UT2102CEL has outlived it's usefulness and it's 1/4 the age of the 465. :-//
Title: Re: True analog scopes
Post by: tautech on December 23, 2022, 06:03:29 am
We called it what it was----a "amplitude/frequency response test".

Back the day, VNAs were "rare as hen's teeth" so we didn't normally have the occasion to do "phase/frequency" testing.

Do the common modern DSOs perform both of these types of test?
FRA is what it's more commonly called today and yes some modern and cheap DSO's do it surprisingly well although for some models an external stimulus is required whereas others have it inbuilt.

Have a look at rf-loop's investigations of the limits of what the little 4ch X-E's can do:
 https://www.eevblog.com/forum/testgear/siglent-sds1x04x-e-bodeplot-ii-(sfra)-features-and-testing-(coming)/ (https://www.eevblog.com/forum/testgear/siglent-sds1x04x-e-bodeplot-ii-(sfra)-features-and-testing-(coming)/)
Title: Re: True analog scopes
Post by: tautech on December 23, 2022, 06:26:38 am
I can also do the timing and adjust the points, synchronize the carbs and prep the plugs on my '74 RD350.  Many here would be at a total loss and never be able to enjoy the feel of riding an untamed, raw twin cylinder 2-stoke bike of epic reputation.  I pity those that cannot appreciate where they, or their world, came from.
Nice bike and when they were all the rage known as real death traps for the unwary due to their raw power.
IIRC they evolved from the RD250 one or maybe both had LC versions too with even more power.
They 250 took the crown from the Suzuki GT250 X7, an air cooled twin and the first mass produced bike to do the ton. (100mph)
https://en.wikipedia.org/wiki/Suzuki_GT250
I had one of the last of these in black with mags and it certainly would do the ton however you always kept your eyes open for an LC Yammy and if one appeared you just nodded and let him go.

Amazed yours has points as mine being near the end of a long production run had upgraded to CDI.


Talking about general purpose scopes for engine tuning a buddy with a 13B twin rotor doorslammer drag car had issues at half track where they we losing power and traced it with a DSO as low output into one coil that at full power and boost was insufficient to keep the fires going.

Even today a DSO gets pulled out to tune max revs on any of my chainsaws that all rev out at some 11k rpm which equates to a very leisurely 183 Hz.
Title: Re: True analog scopes
Post by: tggzzz on December 23, 2022, 09:44:29 am
An especially useful feature of DSOs is the ability to display the waveform in a single sweep before the triggering event.

Agreed, that's something which the unlamented analogue storage scopes couldn't do.

It is less compelling with repetitive waveforms, of course.

Analog 'scopes with delay lines can display the waveform in a recurrent waveform before the trigger event, although it is seldom essential.

Yes, but not by much and only a fixed amount :)

I'll disagree about it being rarely essential. I frequently have to look at the signal integrity and phase relationships of relatively slow digital waveforms. Being able to see the leading edge of a waveform without having to have a very long delay is beneficial. Example: looking at the leading edge of a 10kHz signal with 10ns risetime.
Title: Re: True analog scopes
Post by: Njk on December 23, 2022, 11:33:00 am
We're all living in an environment. Despite the obviousness, the environmental factor is not mentioned it the thread so far. I've two old portable scopes, and I'm also not going to get rid of them any time soon. The scope can operate in wide temperature range, up to -30 degree C. That's nothing exceptional for a service class equipment. It's designed for use in a place like a cold garage or a hangar. That capability is required for a task like to investigate what's wrong with welding machine, which is too big to move indoor. It's a waste of time to figure out the price for a DSO with that capability.

And by the way my shiny new Rigol DSO failed after the first month of use at the lab bench. Sure, it's just Rigol, the other brands of similar breed can never fail, but anyway
Title: Re: True analog scopes
Post by: BillyO on December 23, 2022, 04:53:37 pm
Nice bike and when they were all the rage known as real death traps for the unwary due to their raw power.
IIRC they evolved from the RD250 one or maybe both had LC versions too with even more power.
The 250 and the 350 both evolved from older version.  The RD was first introduced in 1973.  The RD350 followed the R5 and the RD250 followed the DS7.  The big addition to the RD line was reed valves in teh induction.  The 1973 RD350 also got a disk brake over the 1992 R5.  The RD250 did not get the disk until 1974.

The Suzuki GT250 was a decent bike and was Suzuki's 1971 follow-up to it's legendary X6 Hustler.  The X6 had a 6-speed transmission which was really cool at the time.  The GT250 inherited this an got the front disk 3 years before the Yamaha RD250.  By 1974 Gt250 was a good match for the RD250 and could easily hang with it although the RD was a bit nicer in the twisites.  However, the Suzuki GT380 was a bit of an underpowered pig compared to the RD350 and was not even decent competition, performance wise, for it's smaller sibling (GT250).

World wide there were LC versions of both the 250 and 350 but in NA 1974 was the last year for the RD250.

Yeah, my '74 RD has points.  Even my 1976 RD400 had points.
Title: Re: True analog scopes
Post by: Wallace Gasiewicz on December 23, 2022, 08:46:12 pm
My Brother had a Yamaha 350
I had a Harley Sprint 350, actually an Italian MC also 350. 4 stroker.  Aermacchi.
He could barely beat me  from a stop.
But he outweighed me by 40 #

The way to tune an Aermacchi was to adjust the valves and points to "racing specs" and to tune the thing so it would barely run at idle, it would sound terrible at idle but accelerate very well.
Title: Re: True analog scopes
Post by: BillyO on December 23, 2022, 09:20:42 pm
I had a Harley Sprint 350,

My condolences.
Title: Re: True analog scopes
Post by: BillyO on December 23, 2022, 09:21:42 pm
It seems Dave J. likes to have a CRO around too.

https://www.youtube.com/watch?v=8GR_6QH3uZk (https://www.youtube.com/watch?v=8GR_6QH3uZk)
Title: Re: True analog scopes
Post by: tautech on December 23, 2022, 11:08:13 pm
It seems Dave J. likes to have a CRO around too.
:=\
And you dig out an 11 year old video.  ::)

You for one know times have changed and the 3 scopes Dave went on to rabbit about having 500uV/div ranges, well most of Siglent's DSO's have that too.
Title: Re: True analog scopes
Post by: james_s on December 23, 2022, 11:32:33 pm
It seems Dave J. likes to have a CRO around too.

I would think most engineers have one kicking around somewhere. Most don't actually use it often but why get rid of it? Using a CRO is a bit like driving a classic car, it's just fun, and it's still as useful as it ever was.
Title: Re: True analog scopes
Post by: BillyO on December 23, 2022, 11:38:19 pm
It seems Dave J. likes to have a CRO around too.
:=\
And you dig out an 11 year old video.  ::)

You for one know times have changed and the 3 scopes Dave went on to rabbit about having 500uV/div ranges, well most of Siglent's DSO's have that too.
Yes, but the 500uV is why he chose that scope, not why he got himself an analog scope.  He gave several reasons to own an analog scope and they have not changed.

I'd never give up my DSOs and if I was forced to have only one of my scopes it would be my SDS2504XP, but my Tek 465 would not be the fist to go.  I can see only upside to having both.

But I will say I honestly think that if you only had $175 to buy a standalone scope with, you'd get a much better scope going analog.  Just ask all our unfortunate friends here that own FNIRSI and Hantek DSO2x1x scope shaped bricks.
Title: Re: True analog scopes
Post by: tautech on December 23, 2022, 11:51:54 pm
Still, today Dave recommends a DSO. This question has been put to him many times over the years and for the last few a DSO is his recommendation and sure I can hear you all say not everyone has that budget to invest.

Yet if funds were really tight many would consider the investment in old and possibly unreliable technology unwise and force themselves to wait and save for something that will serve them better.
Everyone has their own way of moving forward based on how important an electronics hobby or profession is to them.
Scopes are like eyes into a new world and with the modern feature sets, total investment is dramatically reduced.
Never have we had such good choices at such good pricing.
Title: Re: True analog scopes
Post by: xrunner on December 23, 2022, 11:56:49 pm
Still, today Dave recommends a DSO. This question has been put to him many times over the years and for the last few a DSO is his recommendation and sure I can hear you all say not everyone has that budget to invest.

Yet if funds were really tight many would consider the investment in old and possibly unreliable technology unwise and force themselves to wait and save for something that will serve them better.
Everyone has their own way of moving forward based on how important an electronics hobby or profession is to them.
Scopes are like eyes into a new world and with the modern feature sets, total investment is dramatically reduced.
Never have we had such good choices at such good pricing.

Well Tautech I think I'll up my selection and go for the SDS2202X-E that's my present to myself this year.  8)
Title: Re: True analog scopes
Post by: BillyO on December 24, 2022, 12:17:24 am
Yet if funds were really tight many would consider the investment in old and possibly unreliable technology unwise and force themselves to wait and save for something that will serve them better.
Certainly if the buyer did not have the ability to judge the condition of the scope nor the ability to fix it up, they should not get a used scope of any kind.

Yeah, things are getting wildly better all the time.  My old Uni-T UTD2102CEL was a kick ass scope at the time (the top of Uni-T's 2000 series scopes) but now you can get it's capabilities in a scope that costs under $300.  If you look at the SDS2000XP scopes you'd have to pay the price of a small car to get that capability 12 years ago.  12 years from now we'll probably have 1GHz scopes for $399 with features we can only imagine.
Title: Re: True analog scopes
Post by: tautech on December 24, 2022, 03:35:26 am
Still, today Dave recommends a DSO. This question has been put to him many times over the years and for the last few a DSO is his recommendation and sure I can hear you all say not everyone has that budget to invest.

Yet if funds were really tight many would consider the investment in old and possibly unreliable technology unwise and force themselves to wait and save for something that will serve them better.
Everyone has their own way of moving forward based on how important an electronics hobby or profession is to them.
Scopes are like eyes into a new world and with the modern feature sets, total investment is dramatically reduced.
Never have we had such good choices at such good pricing.

Well Tautech I think I'll up my selection and go for the SDS2202X-E that's my present to myself this year.  8)
IMHO the better feature set is in the 4ch X-E however they are just a 200 MHz design whereas SDS2000X-E are a 350 MHz design so if you only need the BW then 2kX-E is the better choice.
Little things it offers the 1kX-E doesn't are 50 Ohm inputs but it has been left behind with the ongoing rollout of features into the 4ch X-E's.
I've pushed the 350 MHz model past 600 MHz and it still triggered and displayed the frequency.

SDS2202X-E is pretty cheap HP at just $620 considering you can open it up to 350 MHz and it will keep you busy discovering all it can do. Hope it likes you.  ;)
Title: Re: True analog scopes
Post by: tggzzz on December 24, 2022, 10:17:10 am
I've pushed the 350 MHz model past 600 MHz and it still triggered and displayed the frequency.

SDS2202X-E is pretty cheap HP at just $620 considering you can open it up to 350 MHz and it will keep you busy discovering all it can do. Hope it likes you.  ;)

I've pushed my 350MHz Tek 485 past 1.1GHz, and the triggering was rock stable and the waveform was perfectly displayed albeit reduced in amplitude :)

I only paid £50, but a more usual price would be £200. You couldn't make a business out of selling them, thoigh.
Title: Re: True analog scopes
Post by: tautech on December 24, 2022, 10:31:43 am
I've pushed the 350 MHz model past 600 MHz and it still triggered and displayed the frequency.

SDS2202X-E is pretty cheap HP at just $620 considering you can open it up to 350 MHz and it will keep you busy discovering all it can do. Hope it likes you.  ;)

I've pushed my 350MHz Tek 485 past 1.1GHz, and the triggering was rock stable and the waveform was perfectly displayed albeit reduced in amplitude :)
Screenshots required as proof please.

Thanks, needed this push to find the old posts.....with screenshots:
https://www.eevblog.com/forum/testgear/dso-bandwidth-test-sds1104x-e-dsox1102g-to1104-gds1054b/msg2391324/#msg2391324 (https://www.eevblog.com/forum/testgear/dso-bandwidth-test-sds1104x-e-dsox1102g-to1104-gds1054b/msg2391324/#msg2391324)
Title: Re: True analog scopes
Post by: tggzzz on December 24, 2022, 12:46:01 pm
I've pushed the 350 MHz model past 600 MHz and it still triggered and displayed the frequency.

SDS2202X-E is pretty cheap HP at just $620 considering you can open it up to 350 MHz and it will keep you busy discovering all it can do. Hope it likes you.  ;)

I've pushed my 350MHz Tek 485 past 1.1GHz, and the triggering was rock stable and the waveform was perfectly displayed albeit reduced in amplitude :)
Screenshots required as proof please.

I'm away for Christmas, so none are available ATM.

The triggering would have worked at higher frequencies thanks to the tunnel diodes in that part of the circuit. The only reason I couldn't push it further was because the amplitude was reduced to 0.2 div, the min specified for triggering.
Title: Re: True analog scopes
Post by: MrAl on December 24, 2022, 01:34:27 pm
Do true analog scopes still get produced? is there a market for them or specialized applications for which a digital scops is not suitable? I suppose too that a true analog scope couldn't really use a digital display unless the resolution of the screen was huge and that in turn implies there'd need to be some kind of A/D conversion involved, so it wouldn't be true analog scope...

Analog scopes are better for somethings because they can show the difference between regular noise and noise caused by the circuit sometimes when the noise is very small.  The noise can indicate a problem with the circuit and when it is small it could be the scope so you cant tell if it is the scope or the circuit if using a digital scope sometimes.  An analog scope has a very smooth output unless there is noise so the noise will show up differently, sometimes has just one tiny bump.  If the digital scope naturally has several tiny bumps you cant tell if it is the circuit or the scope.

This can be a problem troubleshooting some power converters such as sine synthesized converters that output a nearly clean sine wave.  When i did some troubleshooting long time ago the rule was no digital scopes even though we could have gotten some more information from using one such as FFT.

These days digital scopes are better than back then, but there will always be that scope noise vs circuit noise issue which may or may not be an issue depending on what kind of circuit you are dealing with.

I prefer a digital scope these days because they are so much smaller and once you get to know them you can do a lot with them.  There may be times when you run into a problem though.

For a very extreme example, try illustrating the Lorentz Force Law:
F = qE + qv × B
using a digital scope. It's impossible because there is no electron beam (ha ha) to be influenced by an electrostatic or magnetic field.
With an analog scope it's simple, fast, and easy.  It's also very direct because there are no intermediate sensors required.
Title: Re: True analog scopes
Post by: David Hess on December 24, 2022, 03:24:56 pm
.. they always lack the basic functionality of a true spectrum analyzer, like a noise marker and correction for RBW.  These things would be trivial to add, but for whatever reason DSO designers decline to do so.

Well if they did, how would they convince you to buy their spectrum analyzer?

Perhaps, but the capabilities and use cases are not the same.  A DSO with these features is more comparable to a low frequency network analyzer.

Any sweep function generator with any half-way decent scope with a second channel or external trigger input can do it:

I can tell you that trick is nothing like the real thing.

The usefulness depends a lot on the sweep generator and oscilloscope.  My sweep generator can produce logarithmic sweeps making the display easier to read, and if for instance a Tektronix 2247A or 2236 analog oscilloscope is used, the oscilloscope can place a marker on the screen showing the frequency and separately amplitude at that point.  I have had less success using DSOs like this because they do not make an integrated gated frequency measurement, so their frequency accuracy is more limited.

I think the Tektronix 2465 series with the timer/counter option can work like this also.

You for one know times have changed and the 3 scopes Dave went on to rabbit about having 500uV/div ranges, well most of Siglent's DSO's have that too.

The only reason that the 2225 has a 500 microvolt/division range is that its lower bandwidth design is lower noise which allows it, and it is lower noise than the Siglent DSOs without severe bandwidth limiting or averaging.  That is after taking into account how peak-to-peak noise is displayed on an analog oscilloscope.  Dave did not quantitatively measure the noise of the 2225 when he made that video.

I would still prefer the Signlent DSO to the 2225 baring exceptional circumstances.  I use old oscilloscopes because they are the most cost effective for me, but that is not the case for most people.
Title: Re: True analog scopes
Post by: dave j on December 24, 2022, 04:34:57 pm
It seems Dave J. likes to have a CRO around too.

Oi. I have enough messages from people asking me to review their products in videos because they've confused me with this site's owner ( |O) without you adding to the problem by referring to him using my forum name (see sig). :)
Title: Re: True analog scopes
Post by: mawyatt on December 24, 2022, 05:10:41 pm
The basic problem with the Scope-Sweep Generator method for Bode Plots, and we've used them in the past, is the lack of Vertical dB scales (linear Vertical screen resolution limited to 30~40dB range, and no dynamic V axis scaling), and the lack of any direct Phase plots. The modern DSOs under discussion do a respectable job here, some completely self-contained (built-in AWG), have dB Vertical scales (some with dynamic scaling over 100dB), direct Phase plots, and allow direct digital document recording/printing of the results.

Recall long ago doing the analog Scope-Sweep Generator Bode routines, and having to capture photos of the scope screen, and having very limited Linear vertical scale factors, then having to generate the phase plots by measuring the time delay shift between scope channels, calculating the phase shift, tabulating and hand creating a Phase plot on the Xerox scanned magnified version of the Polaroid image of the scope screen.  :P

We'll take the DSO Bode capability over this Scope-Sweep Generator routine any day, thank you!!

Sure if one has direct access to a Network Analyzer (we did, but these were often under use by others) that's better than the Scope-Sweep Generator routine, or even the modern DSO Bode capability. However, many don't have direct access to a NA, and they tend to be very expensive, even on used market, so a DSO at hand (if available) can serve a very useful purpose here.  :-+

Been around a long long time and done just about every imaginable measurement possible, often even having to design our own test equipment because nothing was available from anyone that could do what was required measurement-wise. Must say these new DSOs are remarkable in the ability to do almost anything and everything a quality analog (Tek) scope could do, and also perform respectable measurements that other dedicated equipment was often acquired for. To add icing on the cake, the relative cost of these modern DSOs is modest, especially compared to their overall capability.

This is from an old diehard analog type, that spent 60+ years with Tek and HP equipment, and finally decided to get our own modern DSO a few years ago (long story) to play around with ;)

Best & Happy Holidays

 
Title: Re: True analog scopes
Post by: nigelwright7557 on December 24, 2022, 09:30:22 pm
I still use an analogue scope.
Bought it about 10 years ago for £45 on ebay.
Channel 2 was faulty when I bought it and still is but can be used if a voltage offset isnt a problem.

I find using software on microcontroller to output signals a distance apart I can get the analogue scope to trigger better.

Most of the stuff I design and build is sub 20MHz so it works fine.

Title: Re: True analog scopes
Post by: tautech on December 26, 2022, 08:02:25 pm
Something I don't miss at all with analogue scopes....all the mental arithmetic just to use the scope vs a DSO that when set correctly excludes all that BS and instead lets you focus on the DUT measurement instead.

Pinched from another thread as a fine example:
(https://i.imgur.com/X90cm5J.jpg)
Apparently using a 100x probe.

 :horse:
Title: Re: True analog scopes
Post by: tggzzz on December 26, 2022, 09:05:48 pm
Something I don't miss at all with analogue scopes....all the mental arithmetic just to use the scope vs a DSO that when set correctly excludes all that BS and instead lets you focus on the DUT measurement instead.

Aw. Bless.

It is really kind of young people to make graybeards feel younger, by favourably comparing graybeards' deteriorating cognitive abilities with the non-deteriorated abilities of the youngsters.

Maybe that suggests a new sales pitch targeting a new demographic..
"Starting to have problems with mental arithmetic? Never mind; conceal it by buying a Siglol oscilloscope".
Title: Re: True analog scopes
Post by: MrAl on December 26, 2022, 09:08:59 pm
Something I don't miss at all with analogue scopes....all the mental arithmetic just to use the scope vs a DSO that when set correctly excludes all that BS and instead lets you focus on the DUT measurement instead.

Pinched from another thread as a fine example:
(https://i.imgur.com/X90cm5J.jpg)
Apparently using a 100x probe.

 :horse:

Yes that's a good point the digital scopes can measure things right away.

I remember years ago trying to measure the rise, slope, and fall times of switching waveforms in high power converters so i could estimate the switching losses.  It took about 15 minutes to get right and the calculation had to be done on a calculator or computer.
If the scope could measure rise and fall times that would help.  Mine does not have that function though but i see some of the upper echelon scopes have that feature.

Title: Re: True analog scopes
Post by: baldurn on December 26, 2022, 09:22:45 pm
I remember years ago trying to measure the rise, slope, and fall times of switching waveforms in high power converters so i could estimate the switching losses.  It took about 15 minutes to get right and the calculation had to be done on a calculator or computer.
If the scope could measure rise and fall times that would help.  Mine does not have that function though but i see some of the upper echelon scopes have that feature.

Does not require upper echelon scope. Just a newer scope. See attached screenshot of what my humble little entry level scope can do.
Title: Re: True analog scopes
Post by: tggzzz on December 26, 2022, 09:24:33 pm
I remember years ago trying to measure the rise, slope, and fall times of switching waveforms in high power converters so i could estimate the switching losses.  It took about 15 minutes to get right and the calculation had to be done on a calculator or computer.

Taking 15mins to work out a rise/slopes/fall times seems long. How long did you take to work out a peak-peak voltage?

OTOH, if it was such an awkward waveform or triggering, what leads you to believe a general purpose scope would have made the same choices?

I can understand that setting up the experiment and transcribing measurements into a very slow computer might have taken 15 mins.
Title: Re: True analog scopes
Post by: tggzzz on December 26, 2022, 09:28:51 pm
I remember years ago trying to measure the rise, slope, and fall times of switching waveforms in high power converters so i could estimate the switching losses.  It took about 15 minutes to get right and the calculation had to be done on a calculator or computer.
If the scope could measure rise and fall times that would help.  Mine does not have that function though but i see some of the upper echelon scopes have that feature.

Does not require upper echelon scope. Just a newer scope. See attached screenshot of what my humble little entry level scope can do.

I would have thought that if traceability and reproducibility was required, then there would be reluctance to rely on a complex black box calculation.

Spreadsheets (and computer programs) often contain errors, but they can be challenged, examined and corrected in a way that firmware cannot.
Title: Re: True analog scopes
Post by: baldurn on December 26, 2022, 09:35:17 pm

I would have thought that if traceability and reproducibility was required, then there would be reluctance to rely on a complex black box calculation.

Spreadsheets (and computer programs) often contain errors, but they can be challenged, examined and corrected in a way that firmware cannot.

If you enable the statistics function to gather data for more than just one random screenshot, there simply is no alternative?

If it is just for one random screenshot, just include that screenshot. Anyone can reproduce the calculation, albeit probably not as precise.
Title: Re: True analog scopes
Post by: Fungus on December 26, 2022, 10:20:36 pm
If the scope could measure rise and fall times that would help.  Mine does not have that function though but i see some of the upper echelon scopes have that feature.

It's an entry-level feature these days. Even the venerable Rigol DS1054Z does it.

Title: Re: True analog scopes
Post by: AVGresponding on December 26, 2022, 10:21:23 pm
Something I don't miss at all with analogue scopes....all the mental arithmetic just to use the scope vs a DSO that when set correctly excludes all that BS and instead lets you focus on the DUT measurement instead.

Pinched from another thread as a fine example:
(https://i.imgur.com/X90cm5J.jpg)
Apparently using a 100x probe.

 :horse:

Yes that's a good point the digital scopes can measure things right away.

I remember years ago trying to measure the rise, slope, and fall times of switching waveforms in high power converters so i could estimate the switching losses.  It took about 15 minutes to get right and the calculation had to be done on a calculator or computer.
If the scope could measure rise and fall times that would help.  Mine does not have that function though but i see some of the upper echelon scopes have that feature.

That's a Tek TDS display. My TDS420A can measure rise times, and fall times. In fact it has 7 pages of things it can measure (4 items to a page in fairness).

How much did I pay for this upper echelon 'scope? £100. Shipped.
Title: Re: True analog scopes
Post by: tggzzz on December 26, 2022, 10:38:35 pm

I would have thought that if traceability and reproducibility was required, then there would be reluctance to rely on a complex black box calculation.

Spreadsheets (and computer programs) often contain errors, but they can be challenged, examined and corrected in a way that firmware cannot.

If you enable the statistics function to gather data for more than just one random screenshot, there simply is no alternative?

If it is just for one random screenshot, just include that screenshot. Anyone can reproduce the calculation, albeit probably not as precise.

MrAl was doing a complex test-specific calculation of switching losses, not a simple standard stats function.  If the measurement is important, it needs to be visible and reproduceable, which is questionable if done inside one specific instrument. (just like a spreadsheet calculation without the formulae being visible)

Here's the relevant context you snipped...
I remember years ago trying to measure the rise, slope, and fall times of switching waveforms in high power converters so i could estimate the switching losses.  It took about 15 minutes to get right and the calculation had to be done on a calculator or computer.
If the scope could measure rise and fall times that would help.  Mine does not have that function though but i see some of the upper echelon scopes have that feature.
Title: Re: True analog scopes
Post by: tggzzz on December 26, 2022, 10:40:51 pm
If the scope could measure rise and fall times that would help.  Mine does not have that function though but i see some of the upper echelon scopes have that feature.

It's an entry-level feature these days. Even the venerable Rigol DS1054Z does it.

If his.calculation was that simple, why did it take 15 mins? If it took 15mins, it would have been so specific and complex that it wouldn't have been a standard scope feature.
Title: Re: True analog scopes
Post by: baldurn on December 26, 2022, 11:18:39 pm

MrAl was doing a complex test-specific calculation of switching losses, not a simple standard stats function.  If the measurement is important, it needs to be visible and reproduceable, which is questionable if done inside one specific instrument. (just like a spreadsheet calculation without the formulae being visible)


Yes and how do you know how precise that measurement is if you do not do statistics on it? Just to be sure, since this thread IS about analog vs DSO, how would you do it with an analog scope (a true analog scope, not those half digital things that can do digital measurements)? I am actually curious and does not know the answer. Would it not be in fact be hard and time consuming to get the same level of precision, that we get by default just by pressing the stat button?
Title: Re: True analog scopes
Post by: tautech on December 26, 2022, 11:55:54 pm
I remember years ago trying to measure the rise, slope, and fall times of switching waveforms in high power converters so i could estimate the switching losses.  It took about 15 minutes to get right and the calculation had to be done on a calculator or computer.
If the scope could measure rise and fall times that would help.  Mine does not have that function though but i see some of the upper echelon scopes have that feature.

Does not require upper echelon scope. Just a newer scope. See attached screenshot of what my humble little entry level scope can do.
Yeah but they are just measurements and sure you can use/apply them for the measurement MrAl was trying to do but in you 2kX+ the PA feature is a far better solution however for best accuracy all/any probes need be de-skew'ed.
Trouble is to complete the full range of PA measurements differential and current probes are required but at least with your 'newer scope' within PA you have connection guides for each type of PA measurement.
Title: Re: True analog scopes
Post by: mag_therm on December 27, 2022, 12:22:04 am
My reply #39 was perhaps a little sarcastic, but that was why I think DSO are not well enough developed yet, still not easy to set up and use, and settings are not persistent and further, not easily accessible or readable.
Also users who rely on capturing a file from equipment to take  back to office, have lost the ability to quickly visualize a problem.

Imagine a 5000 kW inverter that is intermittently tripping at full power.
So we need to run  it at full power with scope probes on it. Shut down, safety rules, blah-blah, change probe position, reset scope, restart
... over and over to find where the problem might be.
It might take 4 to 8 persons, engineers, electricians  mill operators, safety man  etc 4 to 24 hours or 40 hours to do all this.
Then consider what to do with, and the cost of, wasted product. Then consider the down time, loss of production per hour if this unit is mission critical.

When DSO came into use, I saw a step: that it can take the electrician or electronics technician half an hour or more to get usable traces from a basic DSO. Do a setting change to home in on a problem... more delays.  Everybody else standing around and waiting, line shut down.
That was not only anecdote, I saw it as trend in many countries.
And I could compare that to times when we had the old type scopes and recorders which were faster and easier to use.
Title: Re: True analog scopes
Post by: mwb1100 on December 27, 2022, 01:05:24 am
When DSO came into use, I saw a step: that it can take the electrician or electronics technician half an hour or more to get usable traces from a basic DSO. Do a setting change to home in on a problem... more delays.  Everybody else standing around and waiting, line shut down.
That was not only anecdote, I saw it as trend in many countries.
And I could compare that to times when we had the old type scopes and recorders which were faster and easier to use.

This sounds like a technician who is not very well trained or experienced with the test equipment.  Would a similarly untrained technician be able to get results quicker with an analog scope?
Title: Re: True analog scopes
Post by: mag_therm on December 27, 2022, 01:38:03 am


This sounds like a technician who is not very well trained or experienced with the test equipment.  Would a similarly untrained technician be able to get results quicker with an analog scope?
That is an interesting question, and I don't think easy to find out the answer.
That is because new starters in electronics will usually not be exposed to old tech.

I read the aircraft pilots forums where all the present incidents/accidents are discussed.

One of the near disasters was the Qantas flight out of Singapore where an oil pipe in engine broke,
in an early model A380. nearly leading to disaster.
On the flight deck were extra pilots, trained in the management systems.
However they, even collectively,  could not identify key issues, and were searching ( I call "pecking" ) through menus and following procedures,
until fortunately, the aircraft landed safely under manual control.
I may have it a bit wrong, but the official findings are interesting.

We also have stay focussed on the fact that high value engineered stuff stays current for 25 years or more.
That is aircraft, military, space, large industrial , electric power etc.

My opinion is that the underlying tech on the present range of ordinary DSO is following best practice, but the HMI, ergonomics, "intuitiveness" is poor.
Title: Re: True analog scopes
Post by: tautech on December 27, 2022, 01:49:03 am
My reply #39 was perhaps a little sarcastic, but that was why I think DSO are not well enough developed yet, still not easy to set up and use, and settings are not persistent and further, not easily accessible or readable.
Also users who rely on capturing a file from equipment to take  back to office, have lost the ability to quickly visualize a problem.
Consider also the scope novice encountering a waveform they need consult a mentor to understand what they see/have captured.....this is the real power of a DSO that experienced engineers seem to always fail to see.  :-//

This sounds like a technician who is not very well trained or experienced with the test equipment.  Would a similarly untrained technician be able to get results quicker with an analog scope?
My opinion is that the underlying tech on the present range of ordinary DSO is following best practice, but the HMI, ergonomics, "intuitiveness" is poor.
Nothing new, all models of scopes have always offered a different UI presenting just another challenge for the user to learn.
Really the modern DSO is set out on a logical manner with most commonly used features in the top level of menus.
The only difference is one must train oneself to understand the simple logic of where everything is.....press a channel button and everything relating to the channel input is there, coupling, 0V pos, invert, input attenuation and so on.
Greybeards go on as if this basic stuff is from some other planet.  :-//
Title: Re: True analog scopes
Post by: asis on December 27, 2022, 01:52:32 am
Interesting discussion here.

The fact is that no matter how prepared an electronics engineer is, he is not able to quickly make a decision and choose a means of measurement (any) because he needs to quickly restore all previously acquired skills in order to apply them to analyze events.


Well, let's imagine the situation using the example of Neuralink developers with a multi-channel, essentially analog oscilloscope which does not even have any intelligible synchronization.
How should he interpret what he sees in this stream?
Title: Re: True analog scopes
Post by: mag_therm on December 27, 2022, 02:05:35 am

Greybeards go on as if this basic stuff is from some other planet.  :-//
[/quote]

I as graybeered give example of "poor" HMI based on the GWI1202B here

A most basic selection is trigger source.
It requires  3 "pecks" to get the menu followed by a "screwing around" the Variable knob which has no detents.
Try to align it with the selection.
That really puts me off using it.
 I will let the 17 year old here try it and ask him.
Title: Re: True analog scopes
Post by: aeg on December 27, 2022, 02:08:34 am
Something I don't miss at all with analogue scopes....all the mental arithmetic just to use the scope vs a DSO that when set correctly excludes all that BS and instead lets you focus on the DUT measurement instead.

Pinched from another thread as a fine example:
(https://i.imgur.com/X90cm5J.jpg)

OK, I'll bite... If the DSO excludes all the BS, what's that to the left of the rising edge?

Hint: transcendental functions
Title: Re: True analog scopes
Post by: tautech on December 27, 2022, 02:11:45 am
tautech said:
Quote
Greybeards go on as if this basic stuff is from some other planet.  :-//


I as graybeered give example of "poor" HMI based on the GWI1202B here

A most basic selection is trigger source.
It requires  3 "pecks" to get the menu followed by a "screwing around" the Variable knob which has no detents.
Try to align it with the selection.
That really puts me off using it.
 I will let the 17 year old here try it and ask him.
So you have a bad experience with a single brand and you throw all DSO's by implication into the same group ?

That's like saying all opamps are crap just because you can't get one to work like you want to.
Title: Re: True analog scopes
Post by: tautech on December 27, 2022, 02:29:25 am
Something I don't miss at all with analogue scopes....all the mental arithmetic just to use the scope vs a DSO that when set correctly excludes all that BS and instead lets you focus on the DUT measurement instead.

Pinched from another thread as a fine example:
(https://i.imgur.com/X90cm5J.jpg)

OK, I'll bite... If the DSO excludes all the BS, what's that to the left of the rising edge?

Hint: transcendental functions
Gibbs ears, if that's what you mean, DSO's do that too.
Title: Re: True analog scopes
Post by: mag_therm on December 27, 2022, 02:41:56 am

So you have a bad experience with a single brand and you throw all DSO's by implication into the same group ?

That's like saying all opamps are crap just because you can't get one to work like you want to.
Is SDS1000CML current or obsolete? Looks like I can still buy one.
Title: Re: True analog scopes
Post by: tautech on December 27, 2022, 02:49:04 am

So you have a bad experience with a single brand and you throw all DSO's by implication into the same group ?

That's like saying all opamps are crap just because you can't get one to work like you want to.
Is SDS1000CML current or obsolete? Looks like I can still buy one.
Current and now a + version with LAN and other stuff I don't remember....maybe a higher res display than earlier models.
We don't bother with them as the SDS1202X-E is too much next level compared to the older CML design.
Title: Re: True analog scopes
Post by: mag_therm on December 27, 2022, 02:59:50 am
Here, SDS1202X-E  is discontinued and replaced  " SDS1202X+ (DISCONTINUED > SEE SDS1000X-E SERIES)"

Any way these things seem all about same price and tarred by the same brush, see page 33 of SDS1000CML manual.
That is same problem I have with excessive menu depth on the GWInstek.
What is your comment on that?
Title: Re: True analog scopes
Post by: BillyO on December 27, 2022, 04:09:03 am
Greybeards go on as if this basic stuff is from some other planet.  :-//
Hey, don't paint us all with the same brush.  @65yo I'm a greybeard, but I still like, understand and use DSOs.  I still love my old CRO too, though.
Title: Re: True analog scopes
Post by: mag_therm on December 27, 2022, 04:33:09 am
To further my argument that these el cheapo basic  DSO have "poor" HMI:
Both of the following oscilloscopes are on the bench here, (along with a Tek 466, not mentioned here).

Audio work, for example,

Eico TR410 1 CH (year about 1963):
Display area ~ 120 by 120 mm circle
Front panel 200 W by 270 H
Approx 23 control positions status all visible

GWI 1202B 2CH (year about 2017):
Display area ~ 120 by 80 mm rectangle
Front panel 380 W by 200 H
Approx 49 control positions status press/not visible plus menus up to 3 deep, too numerous to count, most status not visible.
(There are 6 controls and underlying menus  dedicated for CH2 and Math)
Title: Re: True analog scopes
Post by: tautech on December 27, 2022, 06:19:41 am
Here, SDS1202X-E  is discontinued and replaced  " SDS1202X+ (DISCONTINUED > SEE SDS1000X-E SERIES)"
See here and the 2ch X-E is on special until years end:
https://siglentna.com/product/sds1202x-e/

Quote
Any way these things seem all about same price and tarred by the same brush, see page 33 of SDS1000CML manual.
That is same problem I have with excessive menu depth on the GWInstek.
What is your comment on that?
Menu depth is relative to feature set depth, pure and simple.

Minimal feature set like with a CRO you can fit all the buttons, knobs and switches on the front panel and have everything visible without any need for a menu.
I went to DSO's in 2009 with a Tek TDS2012B and apart from a little time gaining familiarity with the much greater feature set than a CRO, I never looked back and some 4 years later knowing DSO's were the future and by pure chance I teamed up with Siglent after a little foray with Atten.

The only thing you need do different using a DSO and really it still applies with a CRO is plan a strategy to take a measurement and you do the same with a CRO although after years of using one you don't really know you're doing it.
It's the same just a different path to get the same result.
Now I no longer have or even wish to have a CRO and immersing yourself in DSO usage is far easier as you think about how to take the exact same measurement but in a different manner.

My advice is not to be scared of a menu but instead understand why it is there and what it is for and then learn to use it for best effect which soon will repay you.
We spend years learning all the new devices in the EE world and resist learning the new test equipment technologies ? Why ?  :-//
Title: Re: True analog scopes
Post by: David Hess on December 27, 2022, 06:44:48 am
Excessive menu depth has been a problem with modern DSOs, with very few exceptions, since they have existed.  That problem is not going away.

If you want a simple criteria, which DSOs have a separate slope control?  I can think of a couple, and they are all old enough to drink.  Exclude instruments which can display both slopes at the same time, because those are also old enough to drink.

Title: Re: True analog scopes
Post by: mag_therm on December 27, 2022, 08:05:46 am
Hi tautech, thanks for reply
We will leave the comment about your in-experience with op amp aside.

About user controls: Did you work with transients?
The best 'scope for transients, inverters etc  in my 50 year career was the Tektronics 466 .
I still use one in retirement.   About 9 push buttons in 3 groups.
I am presently working on design of some more inverters, using qucs and the '466.
 I have a plastic DSO there for when it is useful.
Title: Re: True analog scopes
Post by: tautech on December 27, 2022, 08:19:50 am
About user controls: Did you work with transients?
Transients as in fast high current pulses, yes.
Years back I played with simple lead battery desulfators comprising of a battery powered (battery under desulphation) and an optimised pulser delivering ~60V @ 7A at 1kHz.
Carefully tuned to get highest possible magnetics without saturating the core so to get best results without energy wastage.
Some say it's voodoo but when battery OC voltage increases overnight even after powering the desulfator you just know it's improving the status of the plates.

If I weren't so busy catching up with outside jobs after our darn wet spring I should get some screenshots as I never saved any all them years ago. Pulser is somewhere here amongst the messy bench.
Title: Re: True analog scopes
Post by: tggzzz on December 27, 2022, 11:03:12 am

MrAl was doing a complex test-specific calculation of switching losses, not a simple standard stats function.  If the measurement is important, it needs to be visible and reproduceable, which is questionable if done inside one specific instrument. (just like a spreadsheet calculation without the formulae being visible)


Yes and how do you know how precise that measurement is if you do not do statistics on it?

Here's the calculation you again omitted to include...
I remember years ago trying to measure the rise, slope, and fall times of switching waveforms in high power converters so i could estimate the switching losses.  It took about 15 minutes to get right and the calculation had to be done on a calculator or computer.
If the scope could measure rise and fall times that would help.  Mine does not have that function though but i see some of the upper echelon scopes have that feature.

That calculation does not require any statistics. It does require calculus in the form of integration.


Quote
Just to be sure, since this thread IS about analog vs DSO, how would you do it with an analog scope (a true analog scope, not those half digital things that can do digital measurements)? I am actually curious and does not know the answer. Would it not be in fact be hard and time consuming to get the same level of precision, that we get by default just by pressing the stat button?

Strawman argument.

I was responding to what MrAl wrote, not something else.

In future please quote the relevant context; do not attempt to make strawman arguments by omitting context/
Title: Re: True analog scopes
Post by: tggzzz on December 27, 2022, 11:09:24 am
tautech said:
Quote
Greybeards go on as if this basic stuff is from some other planet.  :-//


I as graybeered give example of "poor" HMI based on the GWI1202B here

A most basic selection is trigger source.
It requires  3 "pecks" to get the menu followed by a "screwing around" the Variable knob which has no detents.
Try to align it with the selection.
That really puts me off using it.
 I will let the 17 year old here try it and ask him.
So you have a bad experience with a single brand and you throw all DSO's by implication into the same group ?

That's like saying all opamps are crap just because you can't get one to work like you want to.

All DSOs have that problem in one area or another to a greater or lesser extent.

Opamps all have problems too. It just means you have to carefully select the opamp so that its non-idealities matches your application.
Title: Re: True analog scopes
Post by: tggzzz on December 27, 2022, 11:20:46 am
Excessive menu depth has been a problem with modern DSOs, with very few exceptions, since they have existed.  That problem is not going away.

Precisely.

Another problem that's not going away: when someone's salary depends on selling X, it will difficult to get them to acknowledge problems with X.

Classic OT example: try to get a Tesla salesman to show you how to switch on the windscreen demister safely (i.e. without taking your eyes off the road). Last one I asked only managed to switch on the seat heater; previous one had to reconfigure the GUI including dragging heiroglyphs/icons to a taskbar! When they say you don't have to be watching the road all the time because of its "safety" features", try (in vain) to get them to define what "full self driving (beta)" means in terms of what you aren't responsible for when it is engaged
Title: Re: True analog scopes
Post by: Fungus on December 27, 2022, 12:15:30 pm
Classic OT example: try to get a Tesla salesman to show you how to switch on the windscreen demister safely (i.e. without taking your eyes off the road). Last one I asked only managed to switch on the seat heater; previous one had to reconfigure the GUI including dragging heiroglyphs/icons to a taskbar!

That's because you're asking a stupid question.

The correct way to do it is to press the button then say, "demister on"?
Title: Re: True analog scopes
Post by: Fungus on December 27, 2022, 12:25:19 pm
Excessive menu depth has been a problem with modern DSOs, with very few exceptions, since they have existed.  That problem is not going away.

No, but big touch screens with pictures are on the way. The twisty knob interface will be a thing of the past.

(some of us already have them)
Title: Re: True analog scopes
Post by: David Hess on December 27, 2022, 01:04:20 pm
Excessive menu depth has been a problem with modern DSOs, with very few exceptions, since they have existed.  That problem is not going away.

No, but big touch screens with pictures are on the way. The twisty knob interface will be a thing of the past.

Along with glossy screens which pick up every fingerprint and massive problems with glare from the windows and office lights.
Title: Re: True analog scopes
Post by: robert.rozee on December 27, 2022, 01:53:39 pm

[...] example of "poor" HMI based on the GWI1202B here
[...]
followed by a "screwing around" the Variable knob which has no detents.
Try to align it with the selection.
That really puts me off using it.
[...]

my Siglent SDS-1104X-E has exactly the same problem with the "multi-function" knob lacking detents. other knobs have detents, why not this one?! this is my single greatest complaint about the scope.

it would be great if Tautech could find out from Siglent an exact mechanical replacement part number that does have detents, and do a detailed video on how best to dismantle the scope and replace the detentless offender.

better yet, to hold stock of replacements for those users that are driven nuts by the detentlessness!


cheers,
rob   :-)
Title: Re: True analog scopes
Post by: tggzzz on December 27, 2022, 04:09:01 pm
Classic OT example: try to get a Tesla salesman to show you how to switch on the windscreen demister safely (i.e. without taking your eyes off the road). Last one I asked only managed to switch on the seat heater; previous one had to reconfigure the GUI including dragging heiroglyphs/icons to a taskbar!

That's because you're asking a stupid question.

The correct way to do it is to press the button then say, "demister on"?

After five minutes spent failing to do it with a control, the salesdroid said he could do it with voice control. I said that would be OK with me; he tried, and that's when the seat heater turned on! I didn't bother to ask whether it works just as well while driving and where there's no radio connectivity (think Alexa!)

So, sorry, your suggestion didn't work - and the Tesla failures were worse than you imagined :)
Title: Re: True analog scopes
Post by: tggzzz on December 27, 2022, 04:16:44 pm
Excessive menu depth has been a problem with modern DSOs, with very few exceptions, since they have existed.  That problem is not going away.

No, but big touch screens with pictures are on the way. The twisty knob interface will be a thing of the past.

(some of us already have them)

I know you were thinking of scopes, but applying that principle to car controls...

And how, exactly, does the driver find the right icon with their fingertip when they have their eyes on the road? They must legally have their eyes on the road, since they are legally responsible. (Tesla droids are practitioners of Orwellian DoubleSpeak: you can simultaneously trust the "full self driving (beta)", but must not trust it to have "full self-driving (beta)" responsibility)

Both Tesla droids had their eyes off the road for enough time to have found a cliff or several children. Perhaps you should pull over and stop when you need to change the demister controls?!

(I haven't had a chance to verify David Hess' point, since I've only tried asking a droid inside a shopping centre! His question is valid, though.)
Title: Re: True analog scopes
Post by: Fungus on December 27, 2022, 05:19:00 pm
Quote from: fungus
No, but big touch screens with pictures are on the way. The twisty knob interface will be a thing of the past.

Along with glossy screens which pick up every fingerprint and massive problems with glare from the windows and office lights.

Mine is matte, doesn't show anything.  :-//

Title: Re: True analog scopes
Post by: eti on December 27, 2022, 05:32:11 pm
Ah, the tired old trap people never fail to fall into, thinking “the previous generation is old, outdated, rubbish… but quaint”, just because a new generation is “the norm”.

Human foolishness repeats in a loop. They’re both useful, even if you individually cannot perceive why.
Title: Re: True analog scopes
Post by: tggzzz on December 27, 2022, 06:20:12 pm
Ah, the tired old trap people never fail to fall into, thinking “the previous generation is old, outdated, rubbish… but quaint”, just because a new generation is “the norm”.

Human foolishness repeats in a loop. They’re both useful, even if you individually cannot perceive why.

Yup.

There are famous quotes from George Santayana and Mark Twain about that. Youngsters, if they know them, don't understand them.
Title: Re: True analog scopes
Post by: tautech on December 27, 2022, 07:11:09 pm
my Siglent SDS-1104X-E has exactly the same problem with the "multi-function" knob lacking detents. other knobs have detents, why not this one?! this is my single greatest complaint about the scope.
It does have some impact to the way you use it and for a small knob encoder without detents if pays to use right thumb and forefinger and remaining fingers atop the scope to steady the hand.
Here instead of detents a larger knob would offer better control for rapid adjustment. I have in the past swapped in one of the other knobs which worked quite well but use it as stock and show customers that visit the best way to use it.

I hope to have mine apart soon for some PSU tests, specifically finding the DC levels and currents required to operate a stock unit for portability.
While in there I'll get the encoder info and I guess I need pulses/rotation too.
Pop me mail or PM.
Title: Re: True analog scopes
Post by: james_s on December 27, 2022, 09:31:45 pm
Excessive menu depth has been a problem with modern DSOs, with very few exceptions, since they have existed.  That problem is not going away.

No, but big touch screens with pictures are on the way. The twisty knob interface will be a thing of the past.

Along with glossy screens which pick up every fingerprint and massive problems with glare from the windows and office lights.

I absolutely loathe touchscreens and aside from something like a smartphone I won't buy anything that has one. I absolutely hate fingerprints on a screen, it drives me crazy. Most of them also have frequent issues recognizing touches from my fingers, I've never figured out why that is. Even my iphone sometimes doesn't respond.
Title: Re: True analog scopes
Post by: james_s on December 27, 2022, 09:40:15 pm
Classic OT example: try to get a Tesla salesman to show you how to switch on the windscreen demister safely (i.e. without taking your eyes off the road). Last one I asked only managed to switch on the seat heater; previous one had to reconfigure the GUI including dragging heiroglyphs/icons to a taskbar!

That's because you're asking a stupid question.

The correct way to do it is to press the button then say, "demister on"?

After five minutes spent failing to do it with a control, the salesdroid said he could do it with voice control. I said that would be OK with me; he tried, and that's when the seat heater turned on! I didn't bother to ask whether it works just as well while driving and where there's no radio connectivity (think Alexa!)

So, sorry, your suggestion didn't work - and the Tesla failures were worse than you imagined :)

I drove my dad's Tesla for a few weeks after he passed and I ran into the same issue. I loved the way the car drove but I absolutely hated the dashboard interface. Nearly everything is integrated into that big touchscreen, it is absolutely impossible to operate it safely without using the voice control which is another thing I really don't like doing. It tries to automate some things, like the windshield wipers but it's the edge cases where that fails to work reliably where you need to operating those things manually during times of high driver workload when it is least safe to try hunting around on a touchscreen with one eye on the road. I think touchscreens in cars should be illegal and physical controls mandated. My car has physical controls for everything, knobs, switches and sliders that are laid out logically by function and shaped differently. I can operate everything by feel without taking my eyes off the road even for a moment. It is a demonstrably superior interface but it doesn't look trendy and it is expensive to build.

Touchscreens in cars are marketed as high tech but the only real reason for them is they are cheap.
Title: Re: True analog scopes
Post by: tautech on December 27, 2022, 09:40:58 pm
I absolutely loathe touchscreens and aside from something like a smartphone I won't buy anything that has one. I absolutely hate fingerprints on a screen, it drives me crazy.
Never thought I'd be into them much for test equipment until trying a few and you should be aware a touch based UI is required for a mouse capable instrument.

Some instruments respond to touch, front panel controls and a mouse, including the scroll wheel and use of all 3 once you get in tune with it is much much faster than use of any of their individual input mediums.

Sadly until you spend some time with an instrument with this sort of capability you would never know.
Title: Re: True analog scopes
Post by: tggzzz on December 27, 2022, 10:14:43 pm
Classic OT example: try to get a Tesla salesman to show you how to switch on the windscreen demister safely (i.e. without taking your eyes off the road). Last one I asked only managed to switch on the seat heater; previous one had to reconfigure the GUI including dragging heiroglyphs/icons to a taskbar!

That's because you're asking a stupid question.

The correct way to do it is to press the button then say, "demister on"?

After five minutes spent failing to do it with a control, the salesdroid said he could do it with voice control. I said that would be OK with me; he tried, and that's when the seat heater turned on! I didn't bother to ask whether it works just as well while driving and where there's no radio connectivity (think Alexa!)

So, sorry, your suggestion didn't work - and the Tesla failures were worse than you imagined :)

I drove my dad's Tesla for a few weeks after he passed and I ran into the same issue. I loved the way the car drove but I absolutely hated the dashboard interface. Nearly everything is integrated into that big touchscreen, it is absolutely impossible to operate it safely without using the voice control which is another thing I really don't like doing. It tries to automate some things, like the windshield wipers but it's the edge cases where that fails to work reliably where you need to operating those things manually during times of high driver workload when it is least safe to try hunting around on a touchscreen with one eye on the road. I think touchscreens in cars should be illegal and physical controls mandated. My car has physical controls for everything, knobs, switches and sliders that are laid out logically by function and shaped differently. I can operate everything by feel without taking my eyes off the road even for a moment. It is a demonstrably superior interface but it doesn't look trendy and it is expensive to build.

Touchscreens in cars are marketed as high tech but the only real reason for them is they are cheap.

Practical experience trumps showroom driving :)

In the late 70s a nuke power stations control room had rows of identical dials and levers.

The first thing the operators did was to "decorate" dials and customise levers so that you could tell which one you were holding by touch alone. They knew exactly what they needed and why!

When about to be launched in a glider, I often grasped the airbrake instead of the cable release - a potentially fatal mistake. Fortunately they had very different shapes, so I instantly corrected the mistake.
Title: Re: True analog scopes
Post by: BillyO on December 27, 2022, 10:27:19 pm
Along with glossy screens which pick up every fingerprint and massive problems with glare from the windows and office lights.
You'd be thinking of an Agilent or Tek scope there.  My $1000 Siglent uses a nice matte finish on the screen. :-+
Title: Re: True analog scopes
Post by: Bud on December 27, 2022, 11:19:39 pm
. I loved the way the car drove but I absolutely hated the dashboard interface. Nearly everything is integrated into that big touchscreen, it is absolutely impossible to operate it safely without using the voice control.
A contractor came the other day and we got in his Tesla to discuss things. Radio was playing loud and I watched with amusement him pushing the screen going into menus and sub-menus to just freaking reduce the audio volume down  :-DD
Ah-ha-ha-ha-ha !!  :-DD
Title: Re: True analog scopes
Post by: nctnico on December 27, 2022, 11:34:42 pm
Excessive menu depth has been a problem with modern DSOs, with very few exceptions, since they have existed.  That problem is not going away.

No, but big touch screens with pictures are on the way. The twisty knob interface will be a thing of the past.

Along with glossy screens which pick up every fingerprint and massive problems with glare from the windows and office lights.
That is much less of a problem than you'd think. Speaking from experience here...
Title: Re: True analog scopes
Post by: baldurn on December 28, 2022, 12:00:33 am
. I loved the way the car drove but I absolutely hated the dashboard interface. Nearly everything is integrated into that big touchscreen, it is absolutely impossible to operate it safely without using the voice control.
A contractor came the other day and we got in his Tesla to discuss things. Radio was playing loud and I watched with amusement him pushing the screen going into menus and sub-menus to just freaking reduce the audio volume down  :-DD
Ah-ha-ha-ha-ha !!  :-DD

There is a physical volume control on the steering wheel. It can also mute. There is a physical button at the end of the left stalk to activate the wipers. The only driving related task on the touchscreen is adjusting the wiper speed, but this is always in the lower left corner and can be brought up by pressing the physical button at the end of the left stalk. Alternatively you can use voice command to adjust the wiper speed, which contrary to what some non owners claim here, actually does work.

People love to talk shit but maybe you should just know your car before driving?
Title: Re: True analog scopes
Post by: tggzzz on December 28, 2022, 12:32:52 am
. I loved the way the car drove but I absolutely hated the dashboard interface. Nearly everything is integrated into that big touchscreen, it is absolutely impossible to operate it safely without using the voice control.
A contractor came the other day and we got in his Tesla to discuss things. Radio was playing loud and I watched with amusement him pushing the screen going into menus and sub-menus to just freaking reduce the audio volume down  :-DD
Ah-ha-ha-ha-ha !!  :-DD

There is a physical volume control on the steering wheel. It can also mute. There is a physical button at the end of the left stalk to activate the wipers. The only driving related task on the touchscreen is adjusting the wiper speed, but this is always in the lower left corner and can be brought up by pressing the physical button at the end of the left stalk. Alternatively you can use voice command to adjust the wiper speed, which contrary to what some non owners claim here, actually does work.

People love to talk shit but maybe you should just know your car before driving?

RTFM is always good advice - but as we all know - too few people do it.

Wiper speed is pretty important here. On a 1 hour journey yesterday I changed mine dozens of times.

What is necessary for an averagely incompetent driver to arrange the GUI so that they can touch the wiper speed control and nothing else without taking their eyes off the road for more than a second or two?

Does ventilation - an important safety related "while driving" task - have physical controls? On that same journey I had to change it a couple of times.

If it is so easy and obvious, why did a trained Tesla salesman twice fail to change the ventilation?
Title: Re: True analog scopes
Post by: james_s on December 28, 2022, 01:36:59 am
. I loved the way the car drove but I absolutely hated the dashboard interface. Nearly everything is integrated into that big touchscreen, it is absolutely impossible to operate it safely without using the voice control.
A contractor came the other day and we got in his Tesla to discuss things. Radio was playing loud and I watched with amusement him pushing the screen going into menus and sub-menus to just freaking reduce the audio volume down  :-DD
Ah-ha-ha-ha-ha !!  :-DD

There is a physical volume control on the steering wheel. It can also mute. There is a physical button at the end of the left stalk to activate the wipers. The only driving related task on the touchscreen is adjusting the wiper speed, but this is always in the lower left corner and can be brought up by pressing the physical button at the end of the left stalk. Alternatively you can use voice command to adjust the wiper speed, which contrary to what some non owners claim here, actually does work.

People love to talk shit but maybe you should just know your car before driving?

Ah the old "you're holding it wrong" argument that Apple used several years back.

It wasn't my car, I was tasked with relocating it from my late father's place to my house until we could sort out what to do with it. I figured out the steering wheel controls without too much difficulty, I still had trouble with the wipers. Another issue I had very quickly was figuring out how to turn the headlights off which is required when driving onto the ferry, I don't think there was anywhere to do that other than the touchscreen. Every other car that I have ever driven in my life has physical controls that are more or less standardized for all the important stuff so you don't have to read the manual just to drive the car. It's fairly common for a person to drive a car that is unfamiliar to them, and in ~25 years of driving all sorts of different vehicles this was the first one I couldn't easily figure out on my own.

Whatever the case the touchscreen is useless, there is no way to safely use it while driving so it should not even be able to do anything that you need to do while driving. The only reason not to have physical controls on the dash is cost, they are superior in every way from a functional and ergonomic sense. It's also weird to have even critical stuff like the speedometer off to the side instead of directly ahead of the driver, but again it's cheap, and makes it much cheaper to put the steering wheel on the other side for example with minimal changes to the dash. It's clever in that respect, they need to cut costs as much as possible to make the cars affordable and putting everything on a touchscreen vs traditional controls probably saves several thousand dollars, but from a usability standpoint it sucks.

The Model S though is much better in that respect, a friend of mine has one of those that I've driven a few times and it fixes almost everything I don't like about the Model 3 and Y.
Title: Re: True analog scopes
Post by: james_s on December 28, 2022, 01:39:34 am
Does ventilation - an important safety related "while driving" task - have physical controls? On that same journey I had to change it a couple of times.

If it is so easy and obvious, why did a trained Tesla salesman twice fail to change the ventilation?

No, there are no physical controls at all for any of the HVAC or heated seats, it's entirely done via the touchscreen, voice, or mobile app. The voice commands work pretty well once you get used to it, but I still hate talking to machines, and there are situations, such as a few months ago when I had some kind of illness and almost completely lost my voice for several days that it would have been a proper pain in the ass.
Title: Re: True analog scopes
Post by: H713 on December 28, 2022, 02:07:59 am
I could forgive the detentless multipurpose knob on the Siglent if it weren't for the fact that you push the knob to select. About 30% of the time, it rotates while I'm trying to select something.

As for touchscreen test equipment... I've used plenty. It's better than using a mouse (usually on your pant leg!), but it is still VASTLY inferior to using a knob or switch. It's a good (almost necessary IMO) feature to have in ADDITION to a traditional knob layout for equipment that runs Windows.

In general, the fewer buttons I have to push to take a measurement, the better. The more satisfying the knobs / switches are, the less likely I am to be annoyed by using them. Configuring a Tektronix 547 is very satisfying and it's rare that I will be annoyed while using one, even if I have to think a little harder to accomplish a measurement. Pushing soft buttons (that beep with every push!) on a Siglent is the opposite situation.

Under most circumstances, for a given bandwidth (real bandwidth) a DSO is an objectively better and more useful instrument than an analog scope. Despite this, DSOs are far more likely to annoy me, and when possible, I gravitate towards equipment that doesn't annoy me.

Title: Re: True analog scopes
Post by: TimFox on December 28, 2022, 04:09:29 am
. I loved the way the car drove but I absolutely hated the dashboard interface. Nearly everything is integrated into that big touchscreen, it is absolutely impossible to operate it safely without using the voice control.
A contractor came the other day and we got in his Tesla to discuss things. Radio was playing loud and I watched with amusement him pushing the screen going into menus and sub-menus to just freaking reduce the audio volume down  :-DD
Ah-ha-ha-ha-ha !!  :-DD

There is a physical volume control on the steering wheel. It can also mute. There is a physical button at the end of the left stalk to activate the wipers. The only driving related task on the touchscreen is adjusting the wiper speed, but this is always in the lower left corner and can be brought up by pressing the physical button at the end of the left stalk. Alternatively you can use voice command to adjust the wiper speed, which contrary to what some non owners claim here, actually does work.

People love to talk shit but maybe you should just know your car before driving?

RTFM is always good advice - but as we all know - too few people do it.

Wiper speed is pretty important here. On a 1 hour journey yesterday I changed mine dozens of times.

What is necessary for an averagely incompetent driver to arrange the GUI so that they can touch the wiper speed control and nothing else without taking their eyes off the road for more than a second or two?

Does ventilation - an important safety related "while driving" task - have physical controls? On that same journey I had to change it a couple of times.

If it is so easy and obvious, why did a trained Tesla salesman twice fail to change the ventilation?

One problem with RTFM for a rental car is that the owner's manual is never left in the glove box for the renter to peruse.
Title: Re: True analog scopes
Post by: baldurn on December 28, 2022, 05:15:53 am
Ah the old "you're holding it wrong" argument that Apple used several years back.

No the old "you are wrong". You claimed certain things that are plain wrong, that is not "you are holding it wrong". There are in fact physical controls for some of the stuff that was claimed only to have touch screen controls and that means the car is exactly the same as any other car in that respect.

The _only_ driving related task without physical controls are the wiper speed setting (but wiper activation has a physical control). For the record I think that should have had a physical control as well, but it is not any big deal. Usually the auto setting works.

Stuff like adjusting the heat or the radio (spotify etc), those things are _not_ driving tasks. Feel free to pull over if you are unable to control that in an unfamiliar car. These things can be plenty complicated to control in any unfamiliar car and yes you do look at the radio while tuning even if it has physical controls. You control these things while not too busy with traffic. You are especially NOT able to control all these things in an unfamiliar car by feel alone without looking!

I also own a VW which is my wife's daily driver. She wouldn't know how to change headlight mode because that is done with a knob she _never_ touches. Some people do not care very much about learning about every single feature of the devices they operate (I fear we might have some in this thread). Also to turn on the fog lights, that knob has to be pulled out, something you would never guess without reading the manual. Luckily we do not have to turn off our headlights when entering ferries in this part of the world (we have a headlights always on rule even during daytime).

Title: Re: True analog scopes
Post by: JPortici on December 28, 2022, 06:29:39 am
Whatever the case the touchscreen is useless, there is no way to safely use it while driving so it should not even be able to do anything that you need to do while driving. The only reason not to have physical controls on the dash is cost, they are superior in every way from a functional and ergonomic sense. It's also weird to have even critical stuff like the speedometer off to the side instead of directly ahead of the driver, but again it's cheap, and makes it much cheaper to put the steering wheel on the other side for example with minimal changes to the dash. It's clever in that respect, they need to cut costs as much as possible to make the cars affordable and putting everything on a touchscreen vs traditional controls probably saves several thousand dollars, but from a usability standpoint it sucks.

The real problem is that too much functionality goes through the screen, even some critical functions that one would expect to have a button for, such as opening the trunk/frunk (charging port too? i honestly don't remember), and the screen is not really made to be replaced. We were working with Model 3s last year. One mechanic managed to break the display while installing a rollbar. They ordered a new screen, which wasn't installed perfectly aligned to the 10th of millimiter and the video connector broke inside the screen, 3k euro down the toilet already.
The second screen was installed with even more care because it was taken from a working car. It worked.
But then in order to use the car you had to "update the firmware", which you have to do every time you remove or add a component which has an ECU in it, it doesn't matter if safety related or not. Fair enough, i guess, you have to align ECUs, but we usually have more sane architectures like in VAG vehichles, you connect to the gateway and add/remove the ECU from the installation list. 10 minutes max from when you take the tool to when you put it away.
Instead a full firmware download, install, verify and reboot is required, which is very prone to fail because it's downloaded through the mobile connection in the car, or at least the tesla representative couldn't download it though the ethernet port, and require you to push buttons on the screen at time, which can really become frustrating if the screen decides it doesn't want to respond to touches because it thinks that it's in an unknown vechichle, so it could be from a stolen car. i think it took 10 hours for them to finish the update because it failed at least twice

luckily for the team doing this, they had a guy from the dealership or it would have been impossible. Everything must done through an authorized pc, running an authorized network, while the car is authorized to be serviced.
Title: Re: True analog scopes
Post by: mwb1100 on December 28, 2022, 06:38:56 am
Since this thread jumped the rails long ago, I don’t feel too bad about adding an off topic remark:

I’m pretty sure that a ferry’s “headlights off” rule is for when your car’s engine is turned off.  They like it when your car is able to start when it’s time to debark.  (for the more youthful here, older cars didn’t shut off the headlights when you turned off the ignition.  I never learned why they were designed that way)
Title: Re: True analog scopes
Post by: tautech on December 28, 2022, 06:47:58 am
I could forgive the detentless multipurpose knob on the Siglent if it weren't for the fact that you push the knob to select. About 30% of the time, it rotates while I'm trying to select something.

As for touchscreen test equipment... I've used plenty. It's better than using a mouse (usually on your pant leg!), but it is still VASTLY inferior to using a knob or switch. It's a good (almost necessary IMO) feature to have in ADDITION to a traditional knob layout for equipment that runs Windows.

In general, the fewer buttons I have to push to take a measurement, the better. The more satisfying the knobs / switches are, the less likely I am to be annoyed by using them. Configuring a Tektronix 547 is very satisfying and it's rare that I will be annoyed while using one, even if I have to think a little harder to accomplish a measurement. Pushing soft buttons (that beep with every push!) on a Siglent is the opposite situation.

Under most circumstances, for a given bandwidth (real bandwidth) a DSO is an objectively better and more useful instrument than an analog scope. Despite this, DSOs are far more likely to annoy me, and when possible, I gravitate towards equipment that doesn't annoy me.
:)
After embracing touch and a mouse and the front panel UI, when recently visiting Defpom to drop some items for review we had some time in his lab looking at some of these scopes (new to him) but with the same UI and it was certainly interesting to watch how he used the UI in his own style to get the best from it.

Fast it was too and just different to how I do it but the result was the same which is all that matters.
Is there a right or wrong way, no only what works best for you.
Still with a numeric entry box and a mouse scroll wheel kicks arse of any encoder, detented or not.  :horse:

Then if you must there is also full control via the webserver if it suits to have a PC on the bench or as I've done lately installing options using the webserver SCPI command page and the scope local with the options page visible to watch each option change to permanent at the execution of each license install command.
Copy/Paste saves one heap of time and eliminates any chance of errors.
Title: Re: True analog scopes
Post by: tggzzz on December 28, 2022, 11:17:11 am
I could forgive the detentless multipurpose knob on the Siglent if it weren't for the fact that you push the knob to select. About 30% of the time, it rotates while I'm trying to select something.

Oh... yuck. That sucks.

Quote
As for touchscreen test equipment... I've used plenty. It's better than using a mouse (usually on your pant leg!), but it is still VASTLY inferior to using a knob or switch. It's a good (almost necessary IMO) feature to have in ADDITION to a traditional knob layout for equipment that runs Windows.

There has been one exception of a mouse designed to be used in the air on your lap. I liked it since it worked very well provided you were right handed.

The pop-out mouse-on-a-stick was invented by HP's calculator division and used on their Omnibook 600 and 800 notebooks, which were generally 5 years ahead of everything else!

(https://www.eevblog.com/forum/testgear/true-analog-scopes/?action=dlattach;attach=1673797)

Quote
Under most circumstances, for a given bandwidth (real bandwidth) a DSO is an objectively better and more useful instrument than an analog scope. Despite this, DSOs are far more likely to annoy me, and when possible, I gravitate towards equipment that doesn't annoy me.

Yup. Plus cause puzzlement in beginners that have progressed beyond the "auto setup" button.
Title: Re: True analog scopes
Post by: tggzzz on December 28, 2022, 11:20:37 am
. I loved the way the car drove but I absolutely hated the dashboard interface. Nearly everything is integrated into that big touchscreen, it is absolutely impossible to operate it safely without using the voice control.
A contractor came the other day and we got in his Tesla to discuss things. Radio was playing loud and I watched with amusement him pushing the screen going into menus and sub-menus to just freaking reduce the audio volume down  :-DD
Ah-ha-ha-ha-ha !!  :-DD

There is a physical volume control on the steering wheel. It can also mute. There is a physical button at the end of the left stalk to activate the wipers. The only driving related task on the touchscreen is adjusting the wiper speed, but this is always in the lower left corner and can be brought up by pressing the physical button at the end of the left stalk. Alternatively you can use voice command to adjust the wiper speed, which contrary to what some non owners claim here, actually does work.

People love to talk shit but maybe you should just know your car before driving?

RTFM is always good advice - but as we all know - too few people do it.

Wiper speed is pretty important here. On a 1 hour journey yesterday I changed mine dozens of times.

What is necessary for an averagely incompetent driver to arrange the GUI so that they can touch the wiper speed control and nothing else without taking their eyes off the road for more than a second or two?

Does ventilation - an important safety related "while driving" task - have physical controls? On that same journey I had to change it a couple of times.

If it is so easy and obvious, why did a trained Tesla salesman twice fail to change the ventilation?

One problem with RTFM for a rental car is that the owner's manual is never left in the glove box for the renter to peruse.

Yes indeed.

And even in the unlikely event a renter was prepared to RTFM, they are unlikely to have time to spend before driving away.
Title: Re: True analog scopes
Post by: tggzzz on December 28, 2022, 11:26:34 am
Ah the old "you're holding it wrong" argument that Apple used several years back.

No the old "you are wrong". You claimed certain things that are plain wrong, that is not "you are holding it wrong". There are in fact physical controls for some of the stuff that was claimed only to have touch screen controls and that means the car is exactly the same as any other car in that respect.

You are struggling, and clutching at straws.

Quote
The _only_ driving related task without physical controls are the wiper speed setting (but wiper activation has a physical control). For the record I think that should have had a physical control as well, but it is not any big deal. Usually the auto setting works.

Stuff like adjusting the heat or the radio (spotify etc), those things are _not_ driving tasks.

So the screen ventilation isn't driving related? Well, since you can trust the "full self driving (beta)" to get you safely to your destination, perhaps you don't need to look through the windscreen. (Oh. Wait a minute. You can't. And it would be illegal)

Quote
Feel free to pull over if you are unable to control that in an unfamiliar car.

That would be illegal on many roads, and dangerous on many more.

Quote
These things can be plenty complicated to control in any unfamiliar car and yes you do look at the radio while tuning even if it has physical controls. You control these things while not too busy with traffic. You are especially NOT able to control all these things in an unfamiliar car by feel alone without looking!

With a touchscreen you can't do it safely in cars you have owned for years.
Title: Re: True analog scopes
Post by: tggzzz on December 28, 2022, 11:29:04 am
Instead a full firmware download, install, verify and reboot is required, which is very prone to fail because it's downloaded through the mobile connection in the car, or at least the tesla representative couldn't download it though the ethernet port, and require you to push buttons on the screen at time, which can really become frustrating if the screen decides it doesn't want to respond to touches because it thinks that it's in an unknown vechichle, so it could be from a stolen car. i think it took 10 hours for them to finish the update because it failed at least twice

And after downloading you don't notice the how the "full self driving (beta)" has been updated, so that something that worked safely yesterday does not today.
Title: Re: True analog scopes
Post by: wasedadoc on December 28, 2022, 11:37:44 am
The pop-out mouse-on-a-stick was invented by HP's calculator division and used on their Omnibook 600 and 800 notebooks, which were generally 5 years ahead of everything else!
That mouse debuted on the original Omnibook, the 300.
http://www.computinghistory.org.uk/det/3405/hp-omnibook-300/ (http://www.computinghistory.org.uk/det/3405/hp-omnibook-300/)
Title: Re: True analog scopes
Post by: tggzzz on December 28, 2022, 11:45:34 am
The pop-out mouse-on-a-stick was invented by HP's calculator division and used on their Omnibook 600 and 800 notebooks, which were generally 5 years ahead of everything else!
That mouse debuted on the original Omnibook, the 300.
http://www.computinghistory.org.uk/det/3405/hp-omnibook-300/ (http://www.computinghistory.org.uk/det/3405/hp-omnibook-300/)

Thanks! I didn't have a 300, but did have a 600 and 800. Very useful for a 10 hour plane flight to Palo Alto, since two batteries were sufficient to allow me to play Transport Tycoon Deluxe all the way there :)
Title: Re: True analog scopes
Post by: Fungus on December 28, 2022, 11:53:01 am
I absolutely hate fingerprints on a screen, it drives me crazy.

Use a mouse.

Or a stylus.

(shrug)
Title: Re: True analog scopes
Post by: wasedadoc on December 28, 2022, 11:57:28 am
I did have a 300 and it served me well as my work took me to many parts of the world  but I eventually upgraded to the 800. That was the death of the 300. I inserted a PCMCIA SCSI card and connected to the external CD drive of the 800 package. Bad things happened and the 300 never worked again. Still have the box of bits in the loft.
Title: Re: True analog scopes
Post by: Fungus on December 28, 2022, 12:00:17 pm
I could forgive the detentless multipurpose knob on the Siglent if it weren't for the fact that you push the knob to select. About 30% of the time, it rotates while I'm trying to select something.

Oh... yuck. That sucks.

Yep. I don't understand how that paradigm got past beta testing.

GW-Insteks have a separate button for menu selection.
Title: Re: True analog scopes
Post by: wasedadoc on December 28, 2022, 12:27:51 pm
The detentless multifunction knob on Rigol 1000z series has the same annoying habit of frequently turning when depressed.
Title: Re: True analog scopes
Post by: vk6zgo on December 28, 2022, 02:13:36 pm
Since this thread jumped the rails long ago, I don’t feel too bad about adding an off topic remark:

I’m pretty sure that a ferry’s “headlights off” rule is for when your car’s engine is turned off.  They like it when your car is able to start when it’s time to debark.  (for the more youthful here, older cars didn’t shut off the headlights when you turned off the ignition.  I never learned why they were designed that way)

It was so, if you had to open an unlit gate or door during the hours of darkness, you could leave the headlights on, instead of either leaving the key on, allowing your car to be easily stolen, or to fumble in the dark.

The first car I drove that shut the lights off with the ignition was a nightmare when attending a late-night callout at a remote site.
Many later cars let you leave the lights on for a long enough interval to see what you were doing, then they automatically turned off---the best of both worlds!
Title: Re: True analog scopes
Post by: JPortici on December 28, 2022, 05:06:27 pm
Instead a full firmware download, install, verify and reboot is required, which is very prone to fail because it's downloaded through the mobile connection in the car, or at least the tesla representative couldn't download it though the ethernet port, and require you to push buttons on the screen at time, which can really become frustrating if the screen decides it doesn't want to respond to touches because it thinks that it's in an unknown vechichle, so it could be from a stolen car. i think it took 10 hours for them to finish the update because it failed at least twice

And after downloading you don't notice the how the "full self driving (beta)" has been updated, so that something that worked safely yesterday does not today.

Well, not the same thing but quite. Actually that reminds me of something that happened this morning :) a maserati decided that the best moment to do a full system update was when idling at a semaphore  :-DD the guy freaked out when the idle got up, and the AC started going full blast, then the message appeared on the various screens. The car is updating its software, please do not turn off the car  :-DD
Title: Re: True analog scopes
Post by: tggzzz on December 28, 2022, 06:21:59 pm
Instead a full firmware download, install, verify and reboot is required, which is very prone to fail because it's downloaded through the mobile connection in the car, or at least the tesla representative couldn't download it though the ethernet port, and require you to push buttons on the screen at time, which can really become frustrating if the screen decides it doesn't want to respond to touches because it thinks that it's in an unknown vechichle, so it could be from a stolen car. i think it took 10 hours for them to finish the update because it failed at least twice

And after downloading you don't notice the how the "full self driving (beta)" has been updated, so that something that worked safely yesterday does not today.

Well, not the same thing but quite. Actually that reminds me of something that happened this morning :) a maserati decided that the best moment to do a full system update was when idling at a semaphore  :-DD the guy freaked out when the idle got up, and the AC started going full blast, then the message appeared on the various screens. The car is updating its software, please do not turn off the car  :-DD

Presumably it is running Windoze.

Just as well it wasn't just getting on the Channel Tunnel train, or on a ferry, or at traffic lights in central London/Paris/Rome/Berlin. (Mind you, in Rome I suspect other drivers would have shrugged and driven round it on the pavement.)
Title: Re: True analog scopes
Post by: james_s on December 28, 2022, 06:47:46 pm
As for touchscreen test equipment... I've used plenty. It's better than using a mouse (usually on your pant leg!), but it is still VASTLY inferior to using a knob or switch. It's a good (almost necessary IMO) feature to have in ADDITION to a traditional knob layout for equipment that runs Windows.

I'm of the opinion that Windows has no place in a piece of test equipment. We had a few Windows based instruments at a place I worked at years ago and they were the ones that sat collecting dust. A mouse-centric GUI is ill suited to a benchtop instrument.
Title: Re: True analog scopes
Post by: tautech on December 28, 2022, 06:55:20 pm
A mouse-centric GUI is ill suited to a benchtop instrument.
And several new products are supplied with wireless mice to assist using them.
Yes these are touch instruments too and with physical controls as well.

Properly done it provides a pleasant user experience.

I guess you'd have real trouble with the likes of a Pico scope.
Title: Re: True analog scopes
Post by: tggzzz on December 28, 2022, 07:13:24 pm
As for touchscreen test equipment... I've used plenty. It's better than using a mouse (usually on your pant leg!), but it is still VASTLY inferior to using a knob or switch. It's a good (almost necessary IMO) feature to have in ADDITION to a traditional knob layout for equipment that runs Windows.

I'm of the opinion that Windows has no place in a piece of test equipment. We had a few Windows based instruments at a place I worked at years ago and they were the ones that sat collecting dust. A mouse-centric GUI is ill suited to a benchtop instrument.

There was a version of Windows for Warships
http://catless.ncl.ac.uk/Risks/19/88#subj1.2 (http://catless.ncl.ac.uk/Risks/19/88#subj1.2)
http://catless.ncl.ac.uk/Risks/23/56#subj4.1 (http://catless.ncl.ac.uk/Risks/23/56#subj4.1)
http://catless.ncl.ac.uk/Risks/30/35#subj1.1 (http://catless.ncl.ac.uk/Risks/30/35#subj1.1)
http://catless.ncl.ac.uk/Risks/19/92#subj16.1 (http://catless.ncl.ac.uk/Risks/19/92#subj16.1)
where the last has observations that are directly relevant to "full self driving (beta)" cars.
Title: Re: True analog scopes
Post by: james_s on December 29, 2022, 12:05:16 am
I guess you'd have real trouble with the likes of a Pico scope.

Trouble? No, I'm fully capable of operating one, or at least a similar instrument, I just don't like it. I picked up a BitScope about 15 years ago, it was the only DSO I had at the time and it worked ok but it was never really a great experience. I think I gave it to a friend a few years ago, I hadn't used it even once since getting my TDS scope. If it works for you then great, but I've come to the conclusion through experience that I don't like PC based test equipment.
Title: Re: True analog scopes
Post by: Fungus on December 29, 2022, 12:47:22 am
Well, not the same thing but quite. Actually that reminds me of something that happened this morning :) a maserati decided that the best moment to do a full system update was when idling at a semaphore  :-DD the guy freaked out when the idle got up, and the AC started going full blast, then the message appeared on the various screens. The car is updating its software, please do not turn off the car  :-DD

Was it a "friend-of-a-friend" that it happened to?

I find it hard to believe a car would do any updating while the engine was running.
Title: Re: True analog scopes
Post by: vk6zgo on December 29, 2022, 02:15:40 am
I guess you'd have real trouble with the likes of a Pico scope.

Trouble? No, I'm fully capable of operating one, or at least a similar instrument, I just don't like it. I picked up a BitScope about 15 years ago, it was the only DSO I had at the time and it worked ok but it was never really a great experience. I think I gave it to a friend a few years ago, I hadn't used it even once since getting my TDS scope. If it works for you then great, but I've come to the conclusion through experience that I don't like PC based test equipment.

Those old Bitscopes were pretty dire.
I remember seeing a wildly enthusiastic magazine article on them years ago.

Amongst the screenshots shown was one of a line of PAL analog video.
The rendition of the colour burst was cringeworthy, to say the least.
They didn't attempt a screenshot at field rate! ::)
Title: Re: True analog scopes
Post by: David Hess on December 30, 2022, 06:35:31 pm
Quote from: fungus
Along with glossy screens which pick up every fingerprint and massive problems with glare from the windows and office lights.

Mine is matte, doesn't show anything.  :-//

My new old laptop has a matte screen and is pretty good.  The two desktop monitors I bought last year have matte screens.

Never thought I'd be into them much for test equipment until trying a few and you should be aware a touch based UI is required for a mouse capable instrument.

Some instruments respond to touch, front panel controls and a mouse, including the scroll wheel and use of all 3 once you get in tune with it is much much faster than use of any of their individual input mediums.

Sadly until you spend some time with an instrument with this sort of capability you would never know.

I know that the last thing my workbench needs is a dedicated keyboard and mouse for an oscilloscope, or other test instrument, taking up more space.

In general, the fewer buttons I have to push to take a measurement, the better. The more satisfying the knobs / switches are, the less likely I am to be annoyed by using them. Configuring a Tektronix 547 is very satisfying and it's rare that I will be annoyed while using one, even if I have to think a little harder to accomplish a measurement. Pushing soft buttons (that beep with every push!) on a Siglent is the opposite situation.

There was a lot of optimization by the time of the 547 to reduce the number of needed controls.  The 545 was one of the first true "modern" oscilloscopes and the 547 was the ultimate 545.

Title: Re: True analog scopes
Post by: tautech on December 30, 2022, 07:15:13 pm
Never thought I'd be into them much for test equipment until trying a few and you should be aware a touch based UI is required for a mouse capable instrument.

Some instruments respond to touch, front panel controls and a mouse, including the scroll wheel and use of all 3 once you get in tune with it is much much faster than use of any of their individual input mediums.

Sadly until you spend some time with an instrument with this sort of capability you would never know.

I know that the last thing my workbench needs is a dedicated keyboard and mouse for an oscilloscope, or other test instrument, taking up more space.
Unless you're into a lot of annotating the inbuilt virtual qwerty keyboards that you use with a mouse click or touch work just fine. Numeric boxes can be changed with a mouse scrollwheel or clicked to bring up a virtual keypad.
I've now spent a bit of time using DSO's with touch and mouse and best/fastest performance is gained using all 3 input mediums with screen touch actually the least used.
When done the wireless mouse can sit on the shelf alongside the scope.......zero bench real estate is lost, zero. 

All you doubters really need get yourself in front of one.
Title: Re: True analog scopes
Post by: nctnico on December 30, 2022, 07:24:55 pm
I doubt you ever worked with a piece of test equipment that has a touchscreen UI build from the ground up and not a generic UI with touchscreen interface added on. A real touchscreen UI doesn't need keyboard / mouse; it is better compared to using keyboard + mouse.
Title: Re: True analog scopes
Post by: james_s on December 30, 2022, 07:27:58 pm
I don't think I have, although I've used plenty of iPads and similar devices built from the ground up with a touchscreen and I don't like it. I tolerate a touchscreen on my phone because it's the only practical way to make a pocket sized device usable but I don't type up documents or do anything that requires manual precision on my phone.
Title: Re: True analog scopes
Post by: tautech on December 30, 2022, 07:34:28 pm
I doubt you ever worked with a piece of test equipment that has a touchscreen UI build from the ground up and not a generic UI with touchscreen interface added on. A real touchscreen UI doesn't need keyboard / mouse; it is better compared to using keyboard + mouse.
SDS5000X was the first and after came SDS2000X Plus followed by SDS6000A then SDS2000X HD all developed and continually improved from the first Siglent DSO with a touch UI, 5000X that I owned for some years. As any new UI feature was released in time it was rolled out to all other models too.

Now with that outta the way your presumptions are just that, presumptions.
This UI structure allows for physical or touch or mouse control or any combination of the 3 input mediums.

You too as a doubter need get yourself in front of one.
Title: Re: True analog scopes
Post by: nctnico on December 30, 2022, 08:01:17 pm
FFS, I own several pieces of test equipment which have touch UIs which are designed from the ground up to be touch based. For these I never want or need to use a mouse. OTOH I also have various pieces of test equipment of which the UI is not build for touch but nevertheless a touchscreen was added later, which are easier to operate by a mouse for some operations.
Title: Re: True analog scopes
Post by: BillyO on January 03, 2023, 02:22:51 am
Don't know if it's been mentioned in this thread before, but I had a use case tonight that only my analog scope could help me with and that is being able to trigger independently on two different channels at the same time.  This is something better analog scopes can do but none of my DSOs can.  Well, technically it's not triggering on both signals at exactly the same time, but in alternate mode it shifts the trigger to the channel it is displaying during that sweep.  The effect is both signals, regardless of what frequency they are at, will be displayed properly.

Can any DSO do this?
Title: Re: True analog scopes
Post by: bdunham7 on January 03, 2023, 02:38:24 am
Don't know if it's been mentioned in this thread before, but I had a use case tonight that only my analog scope could help me with and that is being able to trigger independently on two different channels at the same time.  This is something better analog scopes can do but none of my DSOs can.  Well, technically it's not triggering on both signals at exactly the same time, but in alternate mode it shifts the trigger to the channel it is displaying during that sweep.  The effect is both signals, regardless of what frequency they are at, will be displayed properly.

Can any DSO do this?

The Siglent SDS1152CML and and its cousins can do this and they can even have different timebases IIRC.  It's rather unusual for a DSO, common on analog CROs.  I haven't yet seen an actual use case where the SINGLE and ZOOM functions on a DSO couldn't accomplish the task, but I suppose it is possible that there is one.  What were you doing?
Title: Re: True analog scopes
Post by: BillyO on January 03, 2023, 02:52:21 am
I'm writing software for a 6502 based computer I designed to run two digital to analog converters but was (am) having some issues with the outputs of the two converters going bonkers at times.  It's a software problem, but I wanted to see if it happened at specific frequency combinations .. and it does!  So, now I just have to bend my brain around the assembly code and find the bug(s).
Title: Re: True analog scopes
Post by: nctnico on January 03, 2023, 04:48:05 am
Don't know if it's been mentioned in this thread before, but I had a use case tonight that only my analog scope could help me with and that is being able to trigger independently on two different channels at the same time.  This is something better analog scopes can do but none of my DSOs can.  Well, technically it's not triggering on both signals at exactly the same time, but in alternate mode it shifts the trigger to the channel it is displaying during that sweep.  The effect is both signals, regardless of what frequency they are at, will be displayed properly.

Can any DSO do this?
Yes. DSOs from GW Instek have this feature. It can be handy in some situations; I have used it a couple of times.
Title: Re: True analog scopes
Post by: Whitefoot on January 03, 2023, 05:04:19 am
Even my Owon SDS7102 has ALTernate sweep triggering and can trigger on 2 independent signals, both getting the same sweep rate.

You have to be careful thinking of the signals as being displayed properly, since I don't think they are time coincident due to the ALTernate triggering.
Title: Re: True analog scopes
Post by: bdunham7 on January 03, 2023, 05:12:21 am
You have to be careful thinking of the signals as being displayed properly, since I don't think they are time coincident due to the ALTernate triggering.

Yes they aren't.  That's why using a single-shot capture with zoom is often more useful.  Still there may be times when alternate trigger is the easiest way.
Title: Re: True analog scopes
Post by: egonotto on January 04, 2023, 02:11:25 am
Hello,

The VOLTCRAFT DSO-2074G can operate independently of any of the four channels Triggers.
So different time scales and different trigger thresholds.

It is probably a Hantek DSO3064A.
https://www.eevblog.com/forum/testgear/experience-with-dso-2074g/ (https://www.eevblog.com/forum/testgear/experience-with-dso-2074g/)

In the picture you can see two 1kHz signals from two Picoscopes of the 5000'er Series.

But I can't see any real benefit.

Best regards
egonotto