Author Topic: True analog scopes  (Read 50490 times)

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Offline H713

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Re: True analog scopes
« Reply #150 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.

« Last Edit: December 17, 2022, 06:29:11 pm by H713 »
 

Offline Mechatrommer

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Re: True analog scopes
« Reply #151 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...
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock
 

Online tautech

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Re: True analog scopes
« Reply #152 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.
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Offline tggzzz

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Re: True analog scopes
« Reply #153 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 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
  • 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!
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
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Offline H713

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Re: True analog scopes
« Reply #154 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?
 

Offline Mechatrommer

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Re: True analog scopes
« Reply #155 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.
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock
 

Online BillyO

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Re: True analog scopes
« Reply #156 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. :-+
Bill  (Currently a Siglent fanboy)
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Offline tggzzz

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Re: True analog scopes
« Reply #157 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).
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline H713

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Re: True analog scopes
« Reply #158 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.
 

Online tautech

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Re: True analog scopes
« Reply #159 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 !
Avid Rabid Hobbyist.
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Offline Wallace Gasiewicz

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Re: True analog scopes
« Reply #160 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.
 

Offline vk6zgo

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Re: True analog scopes
« Reply #161 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.
 

Offline vk6zgo

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Re: True analog scopes
« Reply #162 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.
 

Online tautech

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Re: True analog scopes
« Reply #163 on: December 18, 2022, 12:33:11 am »
I still think that analog scopes offer easier use at low frequencies.
Please educate us how.  :-//
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Offline tggzzz

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Re: True analog scopes
« Reply #164 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 :(
« Last Edit: December 18, 2022, 12:49:06 am by tggzzz »
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline vk6zgo

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Re: True analog scopes
« Reply #165 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 :(
 

Offline tggzzz

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Re: True analog scopes
« Reply #166 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.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline Wallace Gasiewicz

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Re: True analog scopes
« Reply #167 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.
 

Offline 2N3055

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Re: True analog scopes
« Reply #168 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.
"Just hard work is not enough - it must be applied sensibly."
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Offline Mechatrommer

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Re: True analog scopes
« Reply #169 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...
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock
 

Offline Fungus

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Re: True analog scopes
« Reply #170 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.
 

Offline tggzzz

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Re: True analog scopes
« Reply #171 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.
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline markone

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Re: True analog scopes
« Reply #172 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.
 

Offline vk6zgo

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Re: True analog scopes
« Reply #173 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.
 

Offline Fungus

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Re: True analog scopes
« Reply #174 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.
 


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