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User Experience of Sampling Scopes
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I've spent a few fruitless hours looking for videos of people actually using Tek sampling scopes (e.g. a 7000-series with the 7S11/7T11 plugins) just to see what it's like to use them. Is the user experience any different from using a non-sampling scope (e.g. my trusty 475)? If so, does anybody have a video showing what it's like to use such a scope?
-- Jeff Dutky |
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On Sat, Jan 30, 2021 at 04:28 AM, Dave W1BVV wrote:
I think, you might be confused... these types of scopes, from Tek, et. al. are not new, or even newer... the technology goes all the way back to... perhaps WWII. The theoretical basis is perhaps from the earliest years of the beginning of the last century (so 100 years old... at least), and a theoretical foundation was in place as the result of Nyquist et. al. by the 1930s. |
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They are delicate and complex to setup and use.
Some require a lot of adjustment just to get a trace. Many on epay have issues eg burned out and hard to find tunnel diodes. Unless you have a requirement for super fast sweep and BW over 1 gHz I suggest to stick to the normal scopes and plugins. We use 2467B to 400 MHz, 7904 + 7A29 etc to 500 MHz and 7104 with 7A29 for 1 GHz Bon chance, Jon |
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Roy, I probably was unclear and you miss understood. 1, ¡°new¡± relative to the analog scopes as you mention, 2, ¡°new¡± in that W2EAW as an application engineer seems to have a revolving door of new equipment that he uses In his videos, 3 as an Electrical engineer I am very familiar with sampling theory. I was just trying to point Jeff to some videos made by a guy who knows what he¡¯s doing and uses a variety of equipment including sampling scopes.
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Thank you Miguel, that was almost exactly what I was looking for. I would have liked a little bit of discussion of what was being measured and how, and a little less randomness in the camera work, but I think that gave a really nice fell for what using the sampling plugins on a 7000-series scope is actually like. It looks like a very different experience than using my 475 or 2465.
It's interesting that the displayed waveform retains the sampling, rather than doing anything to interpolate the sampled data. I gather that modern DSOs interpolate the data even in "equivalent time sampling" mode, so that the experience looks a lot more like the normal scope experience. Can anyone tell me if this is also true on the 11000-series scope, or do they keep the individual, sampled dots in the final display? I know that the 11000-series do a lot more computation that earlier scopes, but the only video I've seen of using an 11000-series is marketing material from Tek, which I found less than illuminating: Dave, I am familiar with W2EAW and have watched many of his fine videos, but I was not able to find any that dealt with sampling scopes (I would be happy to be proven wrong, as his videos are always excellent and highly informative). I was, however, more interested in the older sampling instruments, especially in light of the current discussion of the 7T11 plugin. Jean-Paul, I doubt that I have a requirement for even the bandwidth that is currently available to me: my bench is currently home to a 5103N, a 2213 and a 2215A, a 2236, two 475s, a 475A, and a 2465 DMS (no A, no B). I may, if I really stretch, just begin to bump up against the limits of the 475, but even the 2215A is usually more than adequate to me needs. Curiosity, however, is a powerful motivator for me, and I was hoping to satisfy it vicariously, rather than indulging in any more expensive eBay expeditions. -- Jeff Dutky |
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In the video I?m measuring a adjustable oscillator from a tek1405 with a 7S12 through a 30 db attenuator. I?m using a S51 trigger countdown head, it doesn?t have trigger level, has sync trigger min 1:22. When you lost trigger lock you have to adjust it, is a multiturn pot.
At the video beginning I?m showing tunnel diodes test with a DIY VI component tester "The S-51 contains a tunnel diode sync oscillator that oscillates at about 200 MHz (165 MHz to 285 MHz). The input signal is coupled with this oscillator, resulting in injection locking. When locked, fosc is a subharmonic of fin" I have a 7S14 too, if you want I can make a video, I think that I have some photos in photos section. /g/TekScopes/album?id=131745 Regards! -----Mensaje original----- De: [email protected] [mailto:[email protected]] En nombre de Jeff Dutky Enviado el: s¨¢bado, 30 de enero de 2021 21:41 Para: [email protected] Asunto: Re: [TekScopes] User Experience of Sampling Scopes Thank you Miguel, that was almost exactly what I was looking for. I would have liked a little bit of discussion of what was being measured and how, and a little less randomness in the camera work, but I think that gave a really nice fell for what using the sampling plugins on a 7000-series scope is actually like. It looks like a very different experience than using my 475 or 2465. It's interesting that the displayed waveform retains the sampling, rather than doing anything to interpolate the sampled data. I gather that modern DSOs interpolate the data even in "equivalent time sampling" mode, so that the experience looks a lot more like the normal scope experience. Can anyone tell me if this is also true on the 11000-series scope, or do they keep the individual, sampled dots in the final display? I know that the 11000-series do a lot more computation that earlier scopes, but the only video I've seen of using an 11000-series is marketing material from Tek, which I found less than illuminating: Dave, I am familiar with W2EAW and have watched many of his fine videos, but I was not able to find any that dealt with sampling scopes (I would be happy to be proven wrong, as his videos are always excellent and highly informative). I was, however, more interested in the older sampling instruments, especially in light of the current discussion of the 7T11 plugin. Jean-Paul, I doubt that I have a requirement for even the bandwidth that is currently available to me: my bench is currently home to a 5103N, a 2213 and a 2215A, a 2236, two 475s, a 475A, and a 2465 DMS (no A, no B). I may, if I really stretch, just begin to bump up against the limits of the 475, but even the 2215A is usually more than adequate to me needs. Curiosity, however, is a powerful motivator for me, and I was hoping to satisfy it vicariously, rather than indulging in any more expensive eBay expeditions. -- Jeff Dutky Scanned by McAfee and confirmed virus-free. Find out more here: |
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True.? You might find Reg on eevblog.? ? Jim Ford?Sent from my Verizon, Samsung Galaxy smartphone
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-------- Original message --------From: Roy Thistle <roy.thistle@...> Date: 1/30/21 4:36 AM (GMT-08:00) To: [email protected] Subject: Re: [TekScopes] User Experience of Sampling Scopes On Fri, Jan 29, 2021 at 06:07 PM, Jeff Dutky wrote:>> Is the user experience any different from using a non-sampling scope>Look for posts, or PM, Reginald Beardsley ... who is a "nut" for these... I haven't noticed posts from him, for a while.
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Miguel,
Thank you for the explanation. I had noticed the tunnel diode in the photos at the beginning, but couldn't make out what else you were doing. I'm curious what sorts of things you use the sampling scope to do. My hobbies involve 80s vintage computers, and occasionally even older items going back to the 60s, and I think that I understand how I would use a scope like the 475 or 2465 with those systems, but I'm not at all clear what sorts of things one uses a a multi-GHz sampling scope for. I think I looked at some of those photos while following another discussion (not sure if it was recent, or if I found it in a search) about replacing mercury batteries in a sampling plugin with two LEDs, and I've been meaning to play around with that ever since (the other part of my hobby is just seeing interesting physical effects in electronic devices, and lashing two diodes together to get a constant voltage source qualifies). I would be interested in a video 7S14 in action, thank you. -- Jeff Dutky |
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High speed repetitive and fast rise waveforms would be the main thing I can think of. Looking at sinusoidal waveforms is only so interesting...and you probably want to use a spectrum analyzer for that anyway. But something like a Tek 11801 with the right sampling heads can give you crazy large bandpass to look at extremely fast rise pulses (like some of Leo Bodnar's products), and if you're patient it won't break the bank too bad either (relative to the cost of entry for a similarly specified real time scope...)
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Sean On Sat, Jan 30, 2021 at 07:07 PM, Jeff Dutky wrote:
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And one more thing...you can also start doing very fine resolution TDR with such a setup. Good enough to be able to find issues with RF connectors and coax that might not even manifest itself till you're in microwave frequencies!
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Sean On Sat, Jan 30, 2021 at 08:16 PM, @0culus wrote:
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Jeff,
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I had posted still pictures of the conversion of a 7s14 and recommended 3 Watt red LEDs because of the larger surface area that gives more current capability for the receiver (pickup side) with a capacitor to provide stability and, as some had concerns, keep noise (rf or otherwise) from the diodes and fets.? I misstated the physical size as 20 mm, but are about 8 mm LEDs.? I don't recall, but credit to the person who did SPICE (PSPICE on my computer) .? I did a series of empirical data of voltages out for different color LEDs? and posted in earlier Email. Carl Hallberg (W9CJH) On Saturday, January 30, 2021, 09:07:35 PM CST, Jeff Dutky <jeff.dutky@...> wrote:
Miguel, Thank you for the explanation. I had noticed the tunnel diode in the photos at the beginning, but couldn't make out what else you were doing. I'm curious what sorts of things you use the sampling scope to do. My hobbies involve 80s vintage computers, and occasionally even older items going back to the 60s, and I think that I understand how I would use a scope like the 475 or 2465 with those systems, but I'm not at all clear what sorts of things one uses a a multi-GHz sampling scope for. I think I looked at some of those photos while following another discussion (not sure if it was recent, or if I found it in a search) about replacing mercury batteries in a sampling plugin with two LEDs, and I've been meaning to play around with that ever since (the other part of my hobby is just seeing interesting physical effects in electronic devices, and lashing two diodes together to get a constant voltage source qualifies). I would be interested in a video 7S14 in action, thank you. -- Jeff Dutky |
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I'm a big fan of my CSA803A (which is best thought of as an 11803A). Even
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though it's really old, it does things that would need crazy amounts of money to achieve with modern gear. I can look at the integrity of the sort of hundreds-of-megabits-per-second data signals which are common in today's electronics. With the coveted SD-24 TDR head, I can directly characterise transmission lines and measure their impedance and see any disturbances in them, even if they're only millimetres long. To give you an idea of the sort of alchemy that's possible, the TDR resolution is so fine that you can clearly see a short-circuit SMA plug being unscrewed turn-by-turn from the front panel. A few months ago, I used it to find a break in a core of the multicore cable on a Tek A6303 current probe. Just by TDR measurement from the bared wires inside the handle of the probe, It was possible to identify that one core at the other end of 6 feet of cable had broken off the pin in the plug, without taking the plug apart. It's the nearest thing to magic in my lab. Sampling makes it possible. Chris On Sun, 31 Jan 2021, 05:17 , <[email protected]> wrote:
High speed repetitive and fast rise waveforms would be the main thing I |
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Yes, from what I understand, SMA (usually rated to 18 GHz), with its teflon dielectric, and 3.5 mm (26.5 GHz) and 2.92 mm (40 GHz; AKA K connector), with their air dielectrics, are mechanically compatible.
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Whereas the 2.4 mm (50 GHz) and 1.85 mm (67 GHz; AKA V connector) are mechanically compatible with each other but not with the SMA/3.5 mm/2.92 mm connectors. Not sure about the 1.0 mm (110 GHz), the new German 1.35 mm (86 GHz), and the crazy expensive 0.9 mm and 0.8 mm jobs. Last I knew, a 1.0 mm connector was about $1000, so not too many people have them! The only ones I have hands-on experience with (so far) are SMA and 3.5 mm connectors. $ = f^n. I don't know what n is, but it's definitely greater than 1, and probably >2. Yep, I have an S-52 as well, but no S-6 to make a TDR yet. Darn! Had a CSA803 at work back in the day with at least one SD-24. I remember those 3.5 mm connectors. Got to be careful with them, as their center conductors can get out of alignment or broken easily. Jim Ford ------ Original Message ------
From: "snapdiode via groups.io" <snapdiode@...> To: [email protected] Sent: 1/31/2021 1:42:00 PM Subject: Re: [TekScopes] User Experience of Sampling Scopes Well, not to be "that guy", but the SD-24 uses 3.5mm connectors... Compatible with SMA but not the same. |
Jean-Paul
Raymond Domp Frank
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