Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 17686398 times)

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Online tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11575 on: June 02, 2018, 02:36:50 pm »
On the front panel I have everything pulled except the shaft for the Channel 2 variable pot. The allen key isn't long enough to reach down to the set screw so I'll have to be real careful when I pull the board out so as to not break that shaft.

Um, be careful. Get a longer allen key if bnecessary.

Quote
Do the BNC's pull WITH the board or will I have to unsolder them?

You are RTFMing, aren't you? IIRC getting the BNCs out is best avoided.

Quote
I assume the Vertical Mode switch board behind this board pull as one unit, correct?

Yes (unless I'm mentally confusing the 4x5 series, which is entirely possible).

If it is a bugger to get the mode buttons back in, then try popping out the small white plastic inserts so there is a larger hole. Pop the inserts back in after the board is in place.

Quote
Right now I think it's 50/50 that I'll ever get this back together in one piece. But I'm not giving up.

Just follow your notes and photos.
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline Neomys Sapiens

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11576 on: June 02, 2018, 02:45:35 pm »
I have to comment on the ongoing CRO vs. DSO discussion.
My first scope was a HM605 60MHz analogue. I could do some audio, power and digital, and the component tester was a very useful feature in repairs.
But the lack of the possibility to see one-time events left me stranded in many questions. The techniques needed to make those events recurrent were much later aquired by me, I had converted to a DSO before.
And they cannot be applied universally, for example, you can't do that with inrush currents and other power related problems. I had a small Hameg DSO which didn't really count, as it had no measurements and analog output only. But I had some opportunities to work with (then) current DSO's and it was like: THAT is what I want my scope to do. When I got my 2430, it was a real game changer not only because of the storage capability combined with a sensible bandwith-to-sample rate ratio, but because of the measurement functions as well. It was with this scope that I attained the knowledge to make something of a good CRO too.
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11577 on: June 02, 2018, 02:55:57 pm »
When I last looked, a 2430 was a CRO with digital capability as well, or am I missing something here?
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Offline Neomys Sapiens

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11578 on: June 02, 2018, 03:01:59 pm »
When I last looked, a 2430 was a CRO with digital capability as well, or am I missing something here?
Aren't you referring to the 2230?
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11579 on: June 02, 2018, 03:12:04 pm »
When I last looked, a 2430 was a CRO with digital capability as well, or am I missing something here?
Aren't you referring to the 2230?
I assumed that you was talking about a Tek 2430 and according to convention it is a CRO as it uses a Cathode Ray tube as its display medium rather then a LCD or LED screen.
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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11580 on: June 02, 2018, 03:12:46 pm »
On the front panel I have everything pulled except the shaft for the Channel 2 variable pot. The allen key isn't long enough to reach down to the set screw so I'll have to be real careful when I pull the board out so as to not break that shaft.

Um, be careful. Get a longer allen key if bnecessary.

Quote
Do the BNC's pull WITH the board or will I have to unsolder them?

You are RTFMing, aren't you? IIRC getting the BNCs out is best avoided.

Quote
I assume the Vertical Mode switch board behind this board pull as one unit, correct?

Yes (unless I'm mentally confusing the 4x5 series, which is entirely possible).

If it is a bugger to get the mode buttons back in, then try popping out the small white plastic inserts so there is a larger hole. Pop the inserts back in after the board is in place.

Quote
Right now I think it's 50/50 that I'll ever get this back together in one piece. But I'm not giving up.

Just follow your notes and photos.
.
I did RTFM and it's absolutely mute concerning the BNC's which is why I asked the question. So I ASSUME they remain fixed to the board but you know what happens when you assume which is why I asked. As far as the switch board I did initially miss the statement that it does pull with the vertical board.
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11581 on: June 02, 2018, 03:16:57 pm »
.
I did RTFM and it's absolutely mute concerning the BNC's which is why I asked the question. So I ASSUME they remain fixed to the board but you know what happens when you assume which is why I asked. As far as the switch board I did initially miss the statement that it does pull with the vertical board.

All the scopes that I've pulled apart and rebuilt, the BNC's are affixed to the front panel and connected to the boards via a resistor which I unsoldered from the board/
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11582 on: June 02, 2018, 04:31:29 pm »
The "cost of your time" depends on the individual. Some are cash-rich time-poor, some are time-rich cash-poor.

The cost can also be negative, e.g. if repairing something allows you to learn something that is later valued by, say, a potential employer.

While I advise beginners against trying to repair scopes, I get irritated by people that claim that only DSOs should be considered and/or that DSOs are better in all respects. Neither is true.
In what regard are CROs better and why aren't companies capitalizing on that?

We've already seen a very simple, very clear example: finding a glitch in a waveform when you don't have any idea what you're looking for. With an analog scope, that initial diagnosis is as straightforward as adjusting the focus on a microscope, and more importantly, you don't have the question of whether what you see or don;t see is an artifact of the digital sampling process. This is why they are still often found in laboratory settings.

Companies that NEED them that ARE capitalizing on the fact; laboratory-grade CROs with traceable service history and calibration are still trading for serious money in those circles.

The difference is that a good CRO requires a high-quality CRT, which single part would cost more to manufacture today than a whole DSO, even a decent mid-range one.

The death of CROs has nothing to do with whether it is better or not; it has to do with what it costs to make a high-quality CRO vs a high-quality DSO that MAY OR MAY NOT be able to perform as well as a laboratory-grade CRO.

This, coupled with the fact that we now need to be able to troubleshoot digital signals more often than analog, results in the trade-off made for digital: you lose some absolute resolution, and you lose the simple, linear relationship between what you're measuring and what shows up on the screen to the exigencies of digital sampling. That doesn't mean high-quality CROs aren't able to PERFORM; in some cases they can STILL perform better and work better as a diagnostic tool.

Tektronix operated on a different business model than is expected in today's world of greed and multimillion-dollar management payscale; first, they produced bleeding-edge high-tech using the best materials obtainable at the time, BAR NONE. Second, they operated on approximately a 3:1 cost:profit ratio, while today's big business expects closer to a 10:1 ratio, and they do that by pushing as much of their cost onto the 3rd party overseas manufacturing. Third, they manufactured EVERYTHING here in the USA, using USA workforce and paying above-average wages to get the best-qualified workers and to KEEP THEM, as opposed to the current mantra of "reduce cost of workforce by ANY MEANS POSSIBLE", even if that means most of your work is done by incompetents and/or shipped overseas.

Of COURSE that model couldn't survive in THIS "Profit is the only thing that matters" society.   :palm:


mnem
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Offline nixiefreqq

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11583 on: June 02, 2018, 05:26:56 pm »
The "cost of your time" depends on the individual. Some are cash-rich time-poor, some are time-rich cash-poor.

The cost can also be negative, e.g. if repairing something allows you to learn something that is later valued by, say, a potential employer.

While I advise beginners against trying to repair scopes, I get irritated by people that claim that only DSOs should be considered and/or that DSOs are better in all respects. Neither is true.
In what regard are CROs better and why aren't companies capitalizing on that?

We've already seen a very simple, very clear example: finding a glitch in a waveform when you don't have any idea what you're looking for. With an analog scope, that initial diagnosis is as straightforward as adjusting the focus on a microscope, and more importantly, you don't have the question of whether what you see or don;t see is an artifact of the digital sampling process. This is why they are still often found in laboratory settings.

Companies that NEED them that ARE capitalizing on the fact; laboratory-grade CROs with traceable service history and calibration are still trading for serious money in those circles.

The difference is that a good CRO requires a high-quality CRT, which single part would cost more to manufacture today than a whole DSO, even a decent mid-range one.

The death of CROs has nothing to do with whether it is better or not; it has to do with what it costs to make a high-quality CRO vs a high-quality DSO that MAY OR MAY NOT be able to perform as well as a laboratory-grade CRO.

This, coupled with the fact that we now need to be able to troubleshoot digital signals more often than analog, results in the trade-off made for digital: you lose some absolute resolution, and you lose the simple, linear relationship between what you're measuring and what shows up on the screen to the exigencies of digital sampling. That doesn't mean high-quality CROs aren't able to PERFORM; in some cases they can STILL perform better and work better as a diagnostic tool.

Tektronix operated on a different business model than is expected in today's world of greed and multimillion-dollar management payscale; first, they produced bleeding-edge high-tech using the best materials obtainable at the time, BAR NONE. Second, they operated on approximately a 3:1 cost:profit ratio, while today's big business expects closer to a 10:1 ratio, and they do that by pushing as much of their cost onto the 3rd party overseas manufacturing. Third, they manufactured EVERYTHING here in the USA, using USA workforce and paying above-average wages to get the best-qualified workers and to KEEP THEM, as opposed to the current mantra of "reduce cost of workforce by ANY MEANS POSSIBLE", even if that means most of your work is done by incompetents and/or shipped overseas.

Of COURSE that model couldn't survive in THIS "Profit is the only thing that matters" society.   :palm:


mnem
The problem with capitalism in a nutshell: It's propagation model is that of a virus; which means that eventually it kills its host.


that's why milton friedman advocated for "enlightened self interest".

from Wikipedia:

Enlightened self-interest is a philosophy in ethics which states that persons who act to further the interests of others (or the interests of the group or groups to which they belong), ultimately serve their own self-interest.

It has often been simply expressed by the belief that an individual, group, or even a commercial entity will "do well by doing good"

 

greed is a good motivator, but you have to look at the big picture if the goal is long term sustainment.
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Offline BravoV

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11584 on: June 02, 2018, 05:50:14 pm »
Totally disagree, its not a weak argument, so your saying that Dave's advice is also flawed in the same way, he has done a series of scope videos showing how to connect them without blowing the arse out of them which is a typically a thing a beginner might do. I'm not saying that someone a bit more experienced wouldn't to, hell we can all screw up from time to time.

Still, are you saying when a noob that going to get their 1st scope, its the "right" way to get the cheap 10 or 20 bucks used analog scope 1st, not the new affordable DSO even they can afford it ? Learn, and once they blew it, thats for sure according to you, then buy the new DSO.

Thats fine if its what you believe is the right path.


I liken it to just passing your driving test and we all know that does not mean that your a safe driver at all, just means that on the day you reached the required standard for a pass. Once passed would rush off out and secure your that Aston Martin DB8 and probably kill yourself (assuming an insurance company would take you on with such little experience, or buy something more suitable first to gain experience and demonstrate to everyone that you can actually handle a car correctly and not be a hazard to others? That's probably not the best example but you should see the logic in it.

Here is quite different, once passed the driving test and got the license, for sure here I've seen there a lot of parents (not all though) bought their kids "NEW" affordable car like Korean or Japanese car, and some are even allowed them to drive the parent's expensive European car.

Also here we don't have Aston Martin at every house hold, I guess thats our fundamental different, just leave these and stop this argument as I don't see we both going to agree each other.

Call it a day, ok ? Peace.

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11585 on: June 02, 2018, 06:40:50 pm »
Totally disagree, its not a weak argument, so your saying that Dave's advice is also flawed in the same way, he has done a series of scope videos showing how to connect them without blowing the arse out of them which is a typically a thing a beginner might do. I'm not saying that someone a bit more experienced wouldn't to, hell we can all screw up from time to time.

Still, are you saying when a noob that going to get their 1st scope, its the "right" way to get the cheap 10 or 20 bucks used analog scope 1st, not the new affordable DSO even they can afford it ? Learn, and once they blew it, thats for sure according to you, then buy the new DSO.

Thats fine if its what you believe is the right path.


I liken it to just passing your driving test and we all know that does not mean that your a safe driver at all, just means that on the day you reached the required standard for a pass. Once passed would rush off out and secure your that Aston Martin DB8 and probably kill yourself (assuming an insurance company would take you on with such little experience, or buy something more suitable first to gain experience and demonstrate to everyone that you can actually handle a car correctly and not be a hazard to others? That's probably not the best example but you should see the logic in it.

Here is quite different, once passed the driving test and got the license, for sure here I've seen there a lot of parents (not all though) bought their kids "NEW" affordable car like Korean or Japanese car, and some are even allowed them to drive the parent's expensive European car.

Also here we don't have Aston Martin at every house hold, I guess thats our fundamental different, just leave these and stop this argument as I don't see we both going to agree each other.

Call it a day, ok ? Peace.

Peace, yes, its always peace with me. I was not saying it was the "Right Way" just maybe a more sensible option. Neither you or I can make people do anything they don't want to do.

I'm quite sure that a person who had made their mind up that were going to do something, would not post in a forum that they were going to do it. Generally when people do that on a forum they are looking for other viewpoints so that they can benefit from the views and personal experiences then make their own minds up based upon those views.

All that myself and some others are attempting to do is to offer the other side / opinion if you prefer because there are always at least 2 sides to a story.

The car analogy, maybe the Aston Martin was a bit too specific, what I was implying by that is, does it make sense to have driving lessons in a sensible car suitable for a learner, to, once passed the driving test, jump straight into a super car or other high performance car?  In fact in parts of the world you are banned from doing that, and in others you have tp display "P" plates to let others know that your still learning your road craft as a "provisional driver" so that they are made aware that the driver may still make some mistakes that more experienced drivers wouldn't normally make.

I have personal experience of this with my Brother-in-Law who once he passed his test, went and got him self a VW Golf GTI, (Rabbit if your in the USA), despite myself and the rest of the family say no. Why did he do that, simply because he could afford it and he wanted what he thought to be a cool car. He almost killed himself in that car because he was not experienced enough to handle the performance. He is now a lot older and wiser now, drives a Porsche Cayenne and has 2 sons, 1 has just passed his test and he brought him a new car and that car was a Nissan Leaf, electric, why, because it was a safer car to have as his first car and because he remembered how he almost killed himself years ago.

So lets not bogged down in this, its just another point of view, nothing more or less.

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Offline GerryBags

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11586 on: June 02, 2018, 06:59:43 pm »
Tektronix operated on a different business model than is expected in today's world of greed and multimillion-dollar management payscale; first, they produced bleeding-edge high-tech using the best materials obtainable at the time, BAR NONE. Second, they operated on approximately a 3:1 cost:profit ratio, while today's big business expects closer to a 10:1 ratio, and they do that by pushing as much of their cost onto the 3rd party overseas manufacturing. Third, they manufactured EVERYTHING here in the USA, using USA workforce and paying above-average wages to get the best-qualified workers and to KEEP THEM, as opposed to the current mantra of "reduce cost of workforce by ANY MEANS POSSIBLE", even if that means most of your work is done by incompetents and/or shipped overseas.

There is a really interesting old video about Tek's CRT division on VintageTek's YT channel (It was linked in here last time this subject came up, I think), just as it was closing down. They were moving to DSO's and felt they could compete, but everyone seemed aware of the risk they were taking in basically abandoning the edge they'd had over their competitors for half a century. As it turns out, the fears expressed by people such as the guy who headed up the CRT plant were well founded; they have lost their dominance of the oscilloscope market. Even so, they still get a decent slice of it and have survived which might not have been the case if they had clung to the CRO as their focus.

It's always sad to see a unique, effective and successful team of engineers shut down in its prime like that from marketing concerns, but it does seem to have been inevitable with the way that investors matter more than customers to a businesses survival.
 

Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11587 on: June 02, 2018, 07:19:13 pm »
Gang, let's give the DSO/CRO debate a rest and get back to TEA. I think we are at this point :horse: :horse: :horse: and further discussion will just get folks pissed off. 

I did a quick teardown of the Siglent SDS 1052DL DSO. I've never had it apart in the 2 years I've had it. First pix is after cover removal. Fully shielded. And none of the famous Siglent rust that Dave has seen numerous times in his teardowns. 2nd pix looking straight down at the power supply. 3rd pix of the main board. That's as far as I went with the teardown.

Another thing I never did was give it a performance check on the Heath IG-4244 scope calibrator. So here's it's first check and quite frankly I'm impressed. 1MHz, 10MHz. Still pretty decent at 20MHz. And just for giggles I hit it with 50MHz. Not too shabby considering it's advertised bandwidth is 50MHz. This tells me that whatever components are in there they are conservatively rated and capable of higher bandwidth. Maybe I should use this DSO more often instead of just being a bench queen and collecting dust.   :-+
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Offline BravoV

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11588 on: June 02, 2018, 07:26:01 pm »
The death of CROs has nothing to do with whether it is better or not; it has to do with what it costs to make a high-quality CRO vs a high-quality DSO that MAY OR MAY NOT be able to perform as well as a laboratory-grade CRO.

Whats the example of laboratory grade CRO ? I mean for today's standard that is still in use and it's specification.

What about major advancements in ADC technology + powerful silicon say for last 2 decades ? I always thought these are the major aspects for the death of CROs ? CMIIW
 
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Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11589 on: June 02, 2018, 07:28:22 pm »
Thanks for sharing these with us, its nicely laid out but I'm not so sure I approve of the BNC socket being mounted directly onto the PCB, get a sticky plug or a ham fisted person, I can see that coming asunder.

Its shouldn't be a surprise to see it responding to 50MHz input, it is a 50MHz scope after all?
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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11590 on: June 02, 2018, 07:52:00 pm »
Thanks for sharing these with us, its nicely laid out but I'm not so sure I approve of the BNC socket being mounted directly onto the PCB, get a sticky plug or a ham fisted person, I can see that coming asunder.

Its shouldn't be a surprise to see it responding to 50MHz input, it is a 50MHz scope after all?

Keep in mind that's a fast rise time square wave. I would have expected considerably more roll off at 50MHz. I did hit it with 100MHz and it looked almost like a sine wave. That's what I thought would happen at 50MHz and it was a surprise at how good it looked.   
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Online tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11591 on: June 02, 2018, 08:00:01 pm »
I have to comment on the ongoing CRO vs. DSO discussion.
My first scope was a HM605 60MHz analogue. I could do some audio, power and digital, and the component tester was a very useful feature in repairs.
But the lack of the possibility to see one-time events left me stranded in many questions. The techniques needed to make those events recurrent were much later aquired by me, I had converted to a DSO before.

It was easier before there were DSOs. I, like others, instantly structured the design/implementation/debugging style where events were forced to be recurrent :) There was simply no practical alternative, except for those "lucky" people with ASOs.

Quote
And they cannot be applied universally, for example, you can't do that with inrush currents and other power related problems.

Yes, that is indeed a key use-case for DSOs or ASOs.
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11592 on: June 02, 2018, 08:05:38 pm »
Thanks for sharing these with us, its nicely laid out but I'm not so sure I approve of the BNC socket being mounted directly onto the PCB, get a sticky plug or a ham fisted person, I can see that coming asunder.

Its shouldn't be a surprise to see it responding to 50MHz input, it is a 50MHz scope after all?

But that's a 50 MHz square wave being input. Of course one expects a 50MHz sine wave to show up cleanly (at -3 dB), but you need at least decent 3rd harmonic response to resolve something like a square wave and ideally still significant contribution from the 5th harmonic.
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Offline BravoV

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11593 on: June 02, 2018, 08:17:03 pm »
Sod terminating RG8 like that on anything other than N/PL259 though. I’d probably have used RG174 and lost a few dB to be lazy :)

Missed this, it will be on N type and I have these freshly acquired as well. Sigh, RF plumbing miscellaneous thingies are expensive aren't they ?  :'(  :palm:

Offline Mr. Scram

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11594 on: June 02, 2018, 08:57:05 pm »
I don't think that anyone is claiming CROs are better, both CROs and DSOs have advantages over each other. Apart the obvious like the higher cost of a DSO over a 2nd hand CRO, and the size and weight differences, there are differences in the way that they work, screen size etc.

DSOs are good at capturing signals, storing them and allowing them to be displayed /examined in many ways which most CROs cannot. CROs in the main are live only devices with smaller screens and earlier ones do not have screen cursors and wealth of information they can provide unlike DSOs which all have them.

Fact is however that a CRO is more likely the way that beginners will be learning their scope manship on purely on the grounds of cost alone. What makes transistion to DSOs harder is that the interface is so vastly difference with many functions tucked away behind many levels of a menu system requiring multiple pushes of a button to reach.

Fact is that in reality a good electronics bench really needs both of them to accomplish different tasks.

I just wonder if the DSOs of today will still be around on say 20 let alone 40 like so many of the CROs are?

From mobile device so predictive text might have struck again [emoji83]
This is why I'm asking. We see the same statement in different permutations made over and over. CROs have advantages over DSOs. A good work bench needs both. They both have their qualities. However, what's been discussed so far doesn't show that. Proper industry labs don't buy them any more. Half decent manufacturers don't develop them any more. There may be some still in use, but they're definitely on the way out in any industry type setting. Nobody buying a new oscilloscope for the company lab is making a report on which is the more suitable choice.

If there would be a property where the CRO has a distinct and practical advantage over a DSO, this should be reflected in their development and manufacture. We all know development is dead as a dodo. I think the only difference in favour of the CRO that has been discussed here is them being less noisy, but considering we're not seeing special low noise CROs being developed or sold it seems DSO technology has advanced to a point where it simply isn't an issue. As I've said before, the electronics industry is one where niche devices with very specific uses thrive, yet there's no high end low noise CRO market.

Don't get me wrong, I understand where some people are coming from. Because it's a technology that's on the way out, you can get what once was cutting edge black magic voodoo technology for what's essentially chump change. That's fun stuff to play with. The lack of modern features also have a certain charm. It's fun to occasionally write a letter on an old typewriter too. But it seems the romantic notions of some people are getting in the way of their common sense in a bid to justify the equipment they buy and spend their time on.

If you have the room and cash to spare to add a CRO to your collection, by all means. Having a historic perspective never hurts. But it seems that's about as far as it goes.
 
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11595 on: June 02, 2018, 09:11:53 pm »
Sod terminating RG8 like that on anything other than N/PL259 though. I’d probably have used RG174 and lost a few dB to be lazy :)

Missed this, it will be on N type and I have these freshly acquired as well. Sigh, RF plumbing miscellaneous thingies are expensive aren't they ?  :'(  :palm:

Excellent. Nice Amphenol ones too. They are expensive but worth it  :-+
 

Offline bitseekerTopic starter

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11596 on: June 02, 2018, 09:30:27 pm »
As requested by some of the members, here is a small selection of photos from the Shuttleworth evening air show Saturday 19/5/18

...

And these ones were taken at North Weald Airfield when I went to watch the Gnat Display team training for the upcoming display season and was also escorted by a member of the airfield ops team to the opposite end of the airfield which is off limits to the general public, to get some photos of some Jet Provosts coming in to land and also do a few running breaks. There was a lot of general aviation landing and taking off as well and I include just one of these planes landing. Taken on 20/5/18


Awesome photos, Spec! Thanks for posting. Adding to the POI index.

Yeah, I really am this far behind on the thread (page 439 :o). Was busy with other things and now I'm busy attempting to catch up with y'all.
TEA is the way. | TEA Time channel
 

Offline tautech

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11597 on: June 02, 2018, 11:06:52 pm »
Thanks for sharing these with us, its nicely laid out but I'm not so sure I approve of the BNC socket being mounted directly onto the PCB, get a sticky plug or a ham fisted person, I can see that coming asunder.
As seen it's a rear BNC and IIRC inside the enclosure feet/horns so when you roll the DSO over it's clear of the surface it's sitting on.
For the front BNC's Siglent run a proper front panel chassis so every front BNC is nut retained while still part of the PCB. Some new DSO manufacturers still overlook this.  ::)
Tek should've done this too with their early DSO's as they were prone to breaking away from the PCB.
Furthermore they cheaped out and only used a 2 post BNC and the posts broke off.  ::)

The need for decent scope BNC mounting of particularly inputs is well illustrated here:
https://www.eevblog.com/2017/03/31/eevblog-983-a-shocking-oscilloscope-problem/

Well the point is that if you can get a working CRO for a few quids, then thats the way to learn surely and then if they ultimately fuck it up, its just a few quid down the drain rather a few hundred. Better to make your noob mistakes on a cheap piece of equipment rather than making those mistakes become expensive ones. Once your relatively with an old CRO, upgrade to a DSO entry level one or maybe slightly better when you have a better appreciation of what they are and how to use them correctly.

The reason is always they're dirt cheap ... yeah , but you will have to wait, lurk, stalk for good deal, maybe days, weeks or even months.

Also ALWAYS judging that every beginners will 100% and definitely screwed & toasted their 1st scope, and better buy cheap sacrificial one is not a strong argument, c'mon, you have to admit this one is pretty weak.
Totally disagree, its not a weak argument, so your saying that Dave's advice is also flawed in the same way, he has done a series of scope videos showing how to connect them without blowing the arse out of them which is a typically a thing a beginner might do. I'm not saying that someone a bit more experienced wouldn't to, hell we can all screw up from time to time.
It is and he's admitted such that his previous advice to get a CRO first is now superseded with the recent availability of dirt cheap 4ch DSO's.
WRT ground loops, a DSO ground path is pretty robust (excluding an early Tek DSO(factory recalled to fix)) so you're more likely do blow the DUT or a fuse.....if you're supplied with a proper modern earthed supply and not some old 2 wire non-grounded installation.
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Some stuff seen @ Siglent HQ cannot be shared.
 

Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11598 on: June 03, 2018, 01:24:00 am »
I don't think that anyone is claiming CROs are better, both CROs and DSOs have advantages over each other. Apart the obvious like the higher cost of a DSO over a 2nd hand CRO, and the size and weight differences, there are differences in the way that they work, screen size etc.

DSOs are good at capturing signals, storing them and allowing them to be displayed /examined in many ways which most CROs cannot. CROs in the main are live only devices with smaller screens and earlier ones do not have screen cursors and wealth of information they can provide unlike DSOs which all have them.

Fact is however that a CRO is more likely the way that beginners will be learning their scope manship on purely on the grounds of cost alone. What makes transistion to DSOs harder is that the interface is so vastly difference with many functions tucked away behind many levels of a menu system requiring multiple pushes of a button to reach.

Fact is that in reality a good electronics bench really needs both of them to accomplish different tasks.

I just wonder if the DSOs of today will still be around on say 20 let alone 40 like so many of the CROs are?

From mobile device so predictive text might have struck again [emoji83]
This is why I'm asking. We see the same statement in different permutations made over and over. CROs have advantages over DSOs. A good work bench needs both. They both have their qualities. However, what's been discussed so far doesn't show that. Proper industry labs don't buy them any more. Half decent manufacturers don't develop them any more. There may be some still in use, but they're definitely on the way out in any industry type setting. Nobody buying a new oscilloscope for the company lab is making a report on which is the more suitable choice.

If there would be a property where the CRO has a distinct and practical advantage over a DSO, this should be reflected in their development and manufacture. We all know development is dead as a dodo. I think the only difference in favour of the CRO that has been discussed here is them being less noisy, but considering we're not seeing special low noise CROs being developed or sold it seems DSO technology has advanced to a point where it simply isn't an issue. As I've said before, the electronics industry is one where niche devices with very specific uses thrive, yet there's no high end low noise CRO market.

Don't get me wrong, I understand where some people are coming from. Because it's a technology that's on the way out, you can get what once was cutting edge black magic voodoo technology for what's essentially chump change. That's fun stuff to play with. The lack of modern features also have a certain charm. It's fun to occasionally write a letter on an old typewriter too. But it seems the romantic notions of some people are getting in the way of their common sense in a bid to justify the equipment they buy and spend their time on.

If you have the room and cash to spare to add a CRO to your collection, by all means. Having a historic perspective never hurts. But it seems that's about as far as it goes.

What's been discussed HAS shown EXACTLY that; it's not our fault you ignore those parts of the discussion or dismiss them. I've given several examples, and all you have to do is look at all the gear being sold from that Philips 3D LCD lab in Cambridge to see that Analog scopes STILL serve a useful purpose in a laboratory setting.

You seem to think that because laboratory-grade CROs are not being manufactured anymore is reason enough to discount them... Those of us who understand their value are telling you that their death is not entirely due to some fundamental flaw in them, but more the exigencies of profitability and the fact that MOST commercial customers are willing to sacrifice a certain amount of absolute repeating-signal resolution for the strengths of a modern DSO.

Time may very well show that the death of CROs was a foolish economy, and now that the art and science of manufacturing such high-quality CRTs has been lost, something irreplaceable and invaluable was lost as well. I personally feel that is already true.


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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #11599 on: June 03, 2018, 01:51:18 am »
Well the point is that if you can get a working CRO for a few quids, then thats the way to learn surely and then if they ultimately fuck it up, its just a few quid down the drain rather a few hundred. Better to make your noob mistakes on a cheap piece of equipment rather than making those mistakes become expensive ones. Once your relatively with an old CRO, upgrade to a DSO entry level one or maybe slightly better when you have a better appreciation of what they are and how to use them correctly.

The reason is always they're dirt cheap ... yeah , but you will have to wait, lurk, stalk for good deal, maybe days, weeks or even months.

Also ALWAYS judging that every beginners will 100% and definitely screwed & toasted their 1st scope, and better buy cheap sacrificial one is not a strong argument, c'mon, you have to admit this one is pretty weak.
Totally disagree, its not a weak argument, so your saying that Dave's advice is also flawed in the same way, he has done a series of scope videos showing how to connect them without blowing the arse out of them which is a typically a thing a beginner might do. I'm not saying that someone a bit more experienced wouldn't to, hell we can all screw up from time to time.
It is and he's admitted such that his previous advice to get a CRO first is now superseded with the recent availability of dirt cheap 4ch DSO's.
WRT ground loops, a DSO ground path is pretty robust (excluding an early Tek DSO(factory recalled to fix)) so you're more likely do blow the DUT or a fuse.....if you're supplied with a proper modern earthed supply and not some old 2 wire non-grounded installation.

Yeah, except that the current crop of "dirt-cheap DSOs" aren't THAT dirt-cheap, and none of them have the linearly intuitive UI of a recent-production (last 40-ish years) analog scope. Many of them are downright anti-intuitive, like my own 1054Z as you've correctly pointed out. This is what I've argued all along, and you severely overrate that "superseded" statement. He STILL recommends an analog scope as the first scope for anyone NOT in a laboratory or trade-school environment; they have a UI that has developed hand-in-hand with the fundamental laws of electronic theory for nearly a century. The current state of DSOs is... ummm... not there yet.

The concept that comes to my mind is hard to express in a single word... something like "failure to launch" combined with "feature creep" combined with "design scope schizophrenia" combined with "WTF WERE THEY THINKING?!?" is my usual gut reaction even to the best developed DSO UIs I've worked with; and that's saying something, as I was able to figure out most of what my positively Cretaceous 2230 could do before it developed a memory defect.

Cheers,

mnem
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« Last Edit: June 03, 2018, 05:12:37 am by mnementh »
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