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True analog scopes
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Mechatrommer:

--- Quote from: Sherlock Holmes on December 13, 2022, 01:10:17 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.

--- End quote ---
dynamic range is different, noise floor is different.


--- Quote from: Sherlock Holmes on December 13, 2022, 01:53:00 pm ---
--- Quote from: Mechatrommer on December 13, 2022, 01:50:03 pm ---
--- Quote from: Sherlock Holmes on December 13, 2022, 12:13:56 pm ---
--- Quote from: Mechatrommer on December 13, 2022, 10:34:13 am ---
--- Quote from: Sherlock Holmes on December 12, 2022, 09:59:30 pm ---Well, there's zero quantization noise, so I was wandering if some applications find that important?

--- End quote ---
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)?

--- End 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. If you actually watch that video, you'll see he's not talking about quantization noise.

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

--- End quote ---

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!

--- End quote ---
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..


--- Quote from: tggzzz on December 13, 2022, 12:43:05 pm ---
--- Quote from: JPortici on December 13, 2022, 12:29:42 pm ---
--- Quote from: Sherlock Holmes on December 12, 2022, 09:59:30 pm ---Well, there's zero quantization noise, so I was wandering if some applications find that important?

--- End quote ---
Such as? Because I can't think of any

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

--- End quote ---
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.
Mechatrommer:

--- Quote from: tggzzz on December 13, 2022, 02:07:50 pm ---
--- Quote from: JPortici on December 13, 2022, 01:03:39 pm ---
--- Quote from: tggzzz on December 13, 2022, 12:43:05 pm ---Spectrum analysis and allied measurements are a good counter-example.
--- End quote ---
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

--- End quote ---

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

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.

--- End quote ---
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.
vk6zgo:

--- Quote from: tautech on December 13, 2022, 09:16:18 am ---
--- Quote from: 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

--- End quote ---
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


--- 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.

--- End quote ---
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!
--- End quote ---
Just hope you don't need a working scope to do that !

--- End quote ---

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
Sherlock Holmes:

--- Quote from: Mechatrommer on December 13, 2022, 02:20:14 pm ---
--- Quote from: Sherlock Holmes on December 13, 2022, 01:10:17 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.

--- End quote ---
dynamic range is different, noise floor is different.


--- Quote from: Sherlock Holmes on December 13, 2022, 01:53:00 pm ---
--- Quote from: Mechatrommer on December 13, 2022, 01:50:03 pm ---
--- Quote from: Sherlock Holmes on December 13, 2022, 12:13:56 pm ---
--- Quote from: Mechatrommer on December 13, 2022, 10:34:13 am ---
--- Quote from: Sherlock Holmes on December 12, 2022, 09:59:30 pm ---Well, there's zero quantization noise, so I was wandering if some applications find that important?

--- End quote ---
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)?

--- End 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. If you actually watch that video, you'll see he's not talking about quantization noise.

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

--- End quote ---

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!

--- End quote ---
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..


--- Quote from: tggzzz on December 13, 2022, 12:43:05 pm ---
--- Quote from: JPortici on December 13, 2022, 12:29:42 pm ---
--- Quote from: Sherlock Holmes on December 12, 2022, 09:59:30 pm ---Well, there's zero quantization noise, so I was wandering if some applications find that important?

--- End quote ---
Such as? Because I can't think of any

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

--- End quote ---
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.

--- End quote ---

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.
mag_therm:
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.
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