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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/
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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/
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.
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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/
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. -
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
https://www.amazon.co.uk/Portable-Handheld-Oscilloscope-Bandwidth-Transistor/dp/B0B5MZRS35/ref=sr_1_5?keywords=oscilloscope&qid=1670968436&sr=8-5
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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/
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....
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Will your DSOs update fast enough to adjust one oscillator to syntonize with another?
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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. -
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.
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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/
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!
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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
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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.
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.
First is much the same as the cheaper 4ch X-E and this time with a rising trigger.
Or we can punch a STOP to check what's really there:
Our we can go all out and use one of the Zone triggers with a Not Intersect setting
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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.
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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.
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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.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.
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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... -
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 :-) -
Screenshot please.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.
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) -
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. -
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? -
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. -
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 -
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, -
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