Why do Tek TDS210 Scopes sell for so much on Ebay? - Page 1
Forum section: electronics / testgear

author: xrunner
author_rank: Super Contributor
timestamp: March 22, 2015, 11:44:14 pm
content: I was bidding on a signal generator and the same outfit had a Tek TDS210 up starting at $20. I know they are crappy but I put in a few bids on it - I figured it would be worth a few bucks to tinker with. I quit bidding on it when it got to $30. Now it's at $51 and over the next 19 hours I bet it goes to hundreds of dollars.I've seen 'em for sale at $400, $500, and even $700.Why would anyone pay that much for a crappy scope like that - are they collectors' items or something?

author: EEVblog
author_rank: Unknown
timestamp: March 23, 2015, 12:33:54 am
content: People are nuts for nostalgic stuff. I sold a whole bunch, and many went for more than a brand new Rigol.The only advantage I can think of is they are silent, and boot fast. But people who buys these are not thinking rationally.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 23, 2015, 12:47:04 am
content: I still quite often encounter people who don't know that Tek's low-end scopes are an archaic joke. (Even the current ones, let alone the oldies!)It's like the last 20 years never happenned.Farnell & RS still sell 20MHz analogue scopes for £200+And even still stock 1 channel 10Mhz scopesAnd WTF isthisabout?Go figure.....

author: xrunner
author_rank: Super Contributor
timestamp: March 23, 2015, 12:49:00 am
content: Quote from: EEVblog on March 23, 2015, 12:33:54 amOh I can understand it if it's a collector's item or for nostalgia and the people bidding on it know what they are doing. It's worth whatever people pay, I'm just wondering (hoping) that people aren't paying for the name and thinking it's gotta be damn good. I've seen the videos of it and it's not a good scope. Which is why I stopped bidding at $30.I'm going to see what this one I did bid on gets to.

author: EEVblog
author_rank: Unknown
timestamp: March 23, 2015, 12:51:03 am
content: Quote from: xrunner on March 23, 2015, 12:49:00 amIt was a fantastic groundbreaking scope20 years ago.

author: xrunner
author_rank: Super Contributor
timestamp: March 23, 2015, 12:56:40 am
content: Quote from: mikeselectricstuff on March 23, 2015, 12:47:04 am742 GBP = $1109Did I do that right! A 20 MHz scope for $1109? Gulp ...

author: IanB
author_rank: Super Contributor
timestamp: March 23, 2015, 01:12:33 am
content: Quote from: xrunner on March 23, 2015, 12:56:40 amOccasionally there are special circumstances. For instance there might be a diagnostic and maintenance procedure that calls out a specific test instrument (e.g. in the military). Changing the procedure to validate it against a different instrument would be very expensive, so it is cheaper to pay an inflated price to keep the old instrument in production...

author: xrunner
author_rank: Super Contributor
timestamp: March 23, 2015, 01:23:20 am
content: Quote from: IanB on March 23, 2015, 01:12:33 amWell if they know about such a situation with that 20 MHz scope then it's money in the bank.Just for fun I kicked the bid up a couple of times on that TDS210 just to see if there was a max bid entered by somebody - there was. Even if there wasn't a max bid in place, I would have been outbid in a few hours.http://www.ebay.com/itm/311319338779?_trksid=p2055359.m1431.l2649&ssPageName=STRK%3AMEBIDX%3AIT&autorefresh=true

author: EEVblog
author_rank: Unknown
timestamp: March 23, 2015, 01:37:18 am
content: Quote from: xrunner on March 23, 2015, 12:56:40 amThat's more than I paid for mine back in the 80's, even counting for inflation.

author: xrunner
author_rank: Super Contributor
timestamp: March 23, 2015, 01:54:07 am
content: Quote from: blueskull on March 23, 2015, 01:38:02 amYep, if it's legal and there's a market for scopes for stubborn people - hey that's the free market. But they are only keeping themselves in the past.Speaking of the past my current scope is an old 20MHz Hitachi V-212. I want to get a modern one maybe this summer. I haven't needed a better one until recently, but I might have another giveaway. I might ask for help on the shipping costs though.

author: EEVblog
author_rank: Unknown
timestamp: March 23, 2015, 01:59:45 am
content: Quote from: xrunner on March 23, 2015, 01:54:07 amThat was my first work scope at my first job back in 1989

author: xrunner
author_rank: Super Contributor
timestamp: March 23, 2015, 02:24:20 am
content: Quote from: EEVblog on March 23, 2015, 01:59:45 amHa! I bought mine back in ... 1986? It still has the protective film on the front panel. Speaking of nostalgia, I still like it. It's a nice little analog scope. I'd keep it for the memories but I really need to stop that habit and get it to somebody that can use it, plus if I get rid of it it will give me a legitimate excuse to get a new Rigol.

author: EEVblog
author_rank: Unknown
timestamp: March 23, 2015, 02:43:55 am
content: Quote from: xrunner on March 23, 2015, 02:24:20 amThat would have been about the date of my first personal scope:

author: pickle9000
author_rank: Super Contributor
timestamp: March 23, 2015, 02:50:17 am
content: So the 5 dollar question. Do you recommend any scope other than an "intensity graded dso"?I know there are exceptions but a first scope what will it be?My second scope was a TDS 210 it was a great scope but compared to any of today's entry level stuff it's not even worth looking at.

author: nanofrog
author_rank: Super Contributor
timestamp: March 23, 2015, 04:06:05 am
content: Quote from: xrunner on March 23, 2015, 12:56:40 amFWIW, Newark sells it here in the US for $470 (here).

author: Muttley Snickers
author_rank: Unknown
timestamp: March 23, 2015, 04:08:14 am
content: nostalgiaHave a look at what they are getting for old metal lathes,just unbelievable, admittedly though the older lathes were farsuperior than the current garbage unless you spend a packet.I think that it's because some people may have used this gearearlier in their life when they didn't have a hope in hell of beingable to afford one for themselves, trade school, university, etc.Now that they are older and have a bit of spare cash it'sopen slather on all the old gear, I've even heard rumour'sof people collecting old calculator's for god's sake.For some people it's like a time machine that take's themback to a better place and bloody good luck to them I say.Unless their bidding against me of course.PS: I have a pristine Tektronix TDS-1002 in the cupboard,one day I hope to swap it for a house on the beach.Muttley

author: EEVblog
author_rank: Unknown
timestamp: March 23, 2015, 04:52:56 am
content: Quote from: blueskull on March 23, 2015, 04:26:32 am$195 on ebay! BARGAIN!http://www.ebay.com.au/itm/AD390KD-Analog-Devices-12bit-4ch-DAC-/261819595528

author: westfw
author_rank: Super Contributor
timestamp: March 23, 2015, 06:48:27 am
content: I have a TDS210 that I'd be happy to trade for a modern Rigol, if someone is in to its historical value or something.I paid too much for it (when they were new), and don't use it enough, to simply replace it. :-(

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 23, 2015, 08:42:48 am
content: Quote from: pickle9000 on March 23, 2015, 02:50:17 amNot now that they are so cheap.There were some genuine advantages of an analogue scope over early digital ones, but since intensity displays (Agilent 6000, Tek DPO) came in, these advantages disappeared, and it was just a matter of time before prices came down & consigned analogue scopes to history. Just like CRT monitors.

author: daqq
author_rank: Super Contributor
timestamp: March 23, 2015, 08:45:53 am
content: QuoteI googled, the first thing I saw was the new Analog Devices webpage layout, then my eyes began to bleed. Then I noticed the price and I was mystified. Then I saw the gold ceramic extra fancy package and I thought that it must be military, spacey or some such, where price is no object and recertification of new stuff would cost more, and I guess analog devices just decided to milk that cow thoroughly.

author: mzzj
author_rank: Super Contributor
timestamp: March 23, 2015, 09:50:53 am
content: Quote from: Muttley Snickers on March 23, 2015, 04:08:14 amI think comparision to metal lathes is mostly apples to oranges. Okay, some patriotic US brands are overrated if you ask me.Beaten up 12" Southbend used for grinding last 20 years is definetely not worth the money if you compare to some "chinese junk lathes" like Grizzly.

author: EEVblog
author_rank: Unknown
timestamp: March 23, 2015, 11:24:38 am
content: Quote from: pickle9000 on March 23, 2015, 02:50:17 amWhy would you?The sub $400 DS1054Z has one of the best intensity graded displays on the market.

author: EEVblog
author_rank: Unknown
timestamp: March 23, 2015, 11:31:31 am
content: Quote from: Muttley Snickers on March 23, 2015, 04:08:14 amI can understand old analog scopes (specially the high performance ones), but one of the world first budget real-time portable DSO's? Why?I can understand retro collecting, I do it myself, but I just don't get it in this case, and I used to love the TDS-220.Yes, calculators are huge collectible business. The HP calculator craze got very nuts at one point (haven't followed it for a few years).Go try buying the Casio FX-61F, it's becoming quite collectible, or the famed CFX-400 calculator watch! (I sold a broken one for several hundred bucks before the craze for them took off on ebay)

author: coppice
author_rank: Super Contributor
timestamp: March 23, 2015, 12:02:09 pm
content: Quote from: blueskull on March 23, 2015, 04:26:32 amIf an ancient part like that carries a high price tag its usually because it is needed for repairing something highly valuable or irreplaceable, and its in short supply. That's normal market dynamics at work, although its painful when you find the only way forward is to put down the money and buy a part like that.

author: krivx
author_rank: Frequent Contributor
timestamp: March 23, 2015, 12:12:50 pm
content: Quote from: coppice on March 23, 2015, 12:02:09 pmIt's strange that no one has stepped in with a drop-in replacement PCB with a $10 DAC on it...

author: MatthewEveritt
author_rank: Unknown
timestamp: March 23, 2015, 12:16:30 pm
content: I totally agree about the tds210. We've got one or two in dusty corners of the lab and while they're fine for simple things there's no way I'd pay much for one. A while back I forced myself to use one to see how I'd get on with a low end scope at home. In the end I got a hantek 6022e usb price if c**p (for £20), and to be honest I wouldn't swap it.

author: xrunner
author_rank: Super Contributor
timestamp: March 23, 2015, 12:46:46 pm
content: Hahaha - and now the TDS210 scope I bid on when it was $20 is up to $78 ... I bet I could kick it up to $90 0r $100 with no worry of actually having the top bid. There's 6 hours remaining and it's interesting to watch these things in the last few minutes. People will be battling for the last winning bid. The sky's the limit folks!http://www.ebay.com/itm/311319338779?_trksid=p2055359.m1431.l2649&ssPageName=STRK%3AMEBIDX%3AIT

author: dom0
author_rank: Super Contributor
timestamp: March 23, 2015, 01:08:31 pm
content: eBay just goes crazy sometimes. I've seen ancient (50s, early 60s) and beaten up HP generators sell for three figure numbers here... probably some collector stuff or something like that.And here, my dear guests, my rare, valuable and complete collection of early HP sine wave generators *applause*Quote from: krivx on March 23, 2015, 12:12:50 pmYou can bet that that chip is some thoroughly tested and characterized part used in some very sensitive piece of equipment. Designing a fully compatible replacement and testing or maybe even certifying that replacement for use instead of the original part will be much more expensive than the expensive original part.

author: paulie
author_rank: Frequent Contributor
timestamp: March 23, 2015, 04:09:47 pm
content: Quote from: MatthewEveritt on March 23, 2015, 12:16:30 pmIn my shop it's the Rigol shitbox gathering dust in the corner. Played with it for a week then out of sight out of mind. There seems to be some confusion here over usefulness of a gem like my TDS220 compared to 20mhz analog or one those junk chinese 50mhz. I also have a TDS210 retired few years ago and would certainly pull that out before resorting to the christmas tree colors and inscrutable menus buried in the Rigol.But then again I'm famous for using the simplest easiest tool for the job over the most complicated and "pretty".

author: dom0
author_rank: Super Contributor
timestamp: March 23, 2015, 04:35:23 pm
content: Well the screen is good for nothing, 320x240 if I remember correctly, like the first Rigols. Probably any DSO before or after the TDS2xx beat that, easily. I think the higher end CRT DSOs had more than 800 lines or so. And nowadays even the cheapest Chinese DSOs have color 8" screens with 800x480.

author: westfw
author_rank: Super Contributor
timestamp: March 23, 2015, 04:47:42 pm
content: Under $100 doesn't seem like a bad price for a TDS210. Is there a standard compact digital scope on that performance range that regularly sells for < $100? (There are some classic analog scopes, of course, that you can get for little more than the cost of shipping. But shipping those monsters isn't cheap, and not everyone has room for a full-sized scope.)

author: xrunner
author_rank: Super Contributor
timestamp: March 23, 2015, 04:51:26 pm
content: Quote from: westfw on March 23, 2015, 04:47:42 pmI was willing to fork over $20 - $30 for one, but any more than that just seemed like a waste of money in this day and age.But look at the price of it now - it's up to $96 and in the last two hours I guarantee you it will go crazy, so it won't be under $100 ...http://www.ebay.com/itm/311319338779?_trksid=p2055359.m1431.l2649&ssPageName=STRK%3AMEBIDX%3AIT

author: MarkL
author_rank: Unknown
timestamp: March 23, 2015, 04:54:33 pm
content: Quote from: dom0 on March 23, 2015, 01:08:31 pmWhenever I see outrageously priced parts, my first thought is always how the audiophoolery segment might be using it.

author: paulie
author_rank: Frequent Contributor
timestamp: March 23, 2015, 05:01:57 pm
content: Quote from: dom0 on March 23, 2015, 04:35:23 pmIif you want BIG why not get one of those cheap USB PC scopes? Hard to beat a 26" five jillion pixel PC monitor. And the COLORS... lordy! Even if important details were more visible how useful watching those signals fly by or squinting at the captures. And just how important are colors compared to grey scale anyway?I won't even bother to bring up comparisons of my $6 Saleae clone LA with those gorgeous Rigol dealies. Or how many of those you can scatter around the place for the cost of just one.Like I said, "pretty" is not high on my personal list. I need to get things done. Not gaze at holiday lights, spend the day pushing buttons and navigating menus, or try to impress on the internet with 500 thousand dollar wall of equipment behind me.

author: MatthewEveritt
author_rank: Unknown
timestamp: March 23, 2015, 05:23:06 pm
content: Quote from: paulie on March 23, 2015, 04:09:47 pmDepends what you're doing with them, most things we do require pretty and complicated (multiple channels + multiple math + statistics). I don't know about electronics / repair / whatever, but for use in a physics lab the tek is seriously limited. To be fair to it, it is fantastically quick and easy to use for simple things in a way I can't imagine a cheap Rigol is.Of course, the hours I've spent fighting our lecroys have made me somewhat resilient to nasty menu systems.

author: dom0
author_rank: Super Contributor
timestamp: March 23, 2015, 05:31:49 pm
content: Quote from: MarkL on March 23, 2015, 04:54:33 pmI stumbled over this a while ago and I think this is a great example of that which you mentioned:http://www.ti.com/product/opa128First review:QuoteHow did that guy pick this Op (unsuitable for audio, just btw)? Here's my theory: He went to TI. Went to precision amplifier category. Sorted by price. First one is some high power op. Second one is the OPA128. That thing is essentially the most expensive signal op amp TI has. So it must have the best sound, right? Right?

author: Vgkid
author_rank: Super Contributor
timestamp: March 23, 2015, 05:45:53 pm
content: An electrometer grade op-amp for audio

author: paulie
author_rank: Frequent Contributor
timestamp: March 23, 2015, 06:03:11 pm
content: Quote from: MatthewEveritt on March 23, 2015, 05:23:06 pmOf course what you say is 100% correct. I was hoping to get more of a rise out of the Rigol-oids but since that didn't work will admit features on these new scopes are way ahead of oldies like tek. Personally I rarely if ever find need for stuff like RMS or fancy trigger options so the basic type DSO is more useful. For me more important to have all options on the front panel instead of navigating menus.Ironically my TDS210 at couple grand cost more than the used TDS220 and new DS1052E combined. However I wasn't kidding about going back to that TDS210 in an emergency. In fact had to do just that last year when the CFL tubes went on my 220 and had to be replaced with white LED string. They like to do that when it's cold or super important project afoot. Both mine have LEDs now so problem solved. I imagine Rigols come stock like which would be another plus if so.

author: G0HZU
author_rank: Super Contributor
timestamp: March 23, 2015, 06:16:24 pm
content: Quote from: paulie on March 23, 2015, 04:09:47 pmAgreed. At my place of work the TDS220 and TDS20xx are still very popular scopes and we still have dozens of them. They have their limitations (and are also Chinese made) but when used with some sympathy for these limitations they are still a very useful toolI can't see a Rigol scope being 'accepted' or taken seriously at work because of their crappy reputation for bugs and poor service etc.I paid about £550 for my TDS2012 some 10 years ago and I still use it here at home today. At work I have access to all kinds of modern, powerful scopes from Tek/Agilent/R&S but I nearly always reach for a TDS2012 or TDS2022 instead because it's often the case that 'less is more'. Often, the little TDS can do the job and can do it quicker and hardly takes up space and is totally silent in operationI think the reason the TDS scopes hold their value is because they are a known industry scope that is easy to use and offers good reliability and may users are familiar with the UI. In terms of performance they're pretty lame compared to a modern scope but that doesn't mean they have no appeal or demand today.

author: pickle9000
author_rank: Super Contributor
timestamp: March 23, 2015, 06:16:24 pm
content: When it comes to menus you would think after all this time a single customizable start menu would be standard. Low overhead and easy to implement. It would be so nice to have your to favorite 5-10 functions ready to go after startup.

author: nctnico
author_rank: Super Contributor
timestamp: March 23, 2015, 06:52:01 pm
content: I have used a TDS220 in the past but I was very happy I could replace it with an Iwatsu DS-8617:I don't see how a TDS200 series can be better in any way compared to a mainstream Rigol or Siglent scope. Feature wise the TDS200 is dwarfed by what Rigol and Siglent offer as standard nowadays.

author: MatthewEveritt
author_rank: Unknown
timestamp: March 23, 2015, 06:53:09 pm
content: I do have a lot of affection for the tds2024 I must admit. I wouldn't relish trying to explain what 4 black and white traces all mean though, colour screens are a must.This raises an interesting question though, how many features do most peopleactuallyever use? Half the time all Ireallyneed is decent averaging and some simple measurements.

author: dom0
author_rank: Super Contributor
timestamp: March 23, 2015, 07:25:22 pm
content: Well a scope with a propertrigger counteris nice, most have that and while not a great counter it doesn't take any desk space or cost any money.Having automaticpeak, peak-peak and RMS measurementsis handy, too, esp. RMS since that's not easily worked out from for complex waveformsDeep memoryis a must for some things, others will never notice itFilters (including averaging). I wish more scopes had arbitrary filters (LPF/HPF/BPF), but most have at least selectable bandwidth, so that's a start. A 500 MHz scope would be quite useless for many things if it didn't have a LPF option.FFTis handy for similar reasons as the trigger counter, although you'll get more from the DSOs' AFE if you export the waveform data and use some PC based software to analyze itDecent resolution color screen. A scope is about seeing things. Not much to see with a crap screen.Intensity gradingshould be standard.Unnecessary (IMHO): decoding (most scopes can't decode much, and it's completely useless on 2 ch models), front panel presets, auto set, unnecessary built in help, stupid dials that are hard to adjust (heeeellooo, hantek 5000 series)

author: Muttley Snickers
author_rank: Unknown
timestamp: March 24, 2015, 08:36:38 pm
content: Thirty buck's for shipping and no local pickup, that's bullshit it's only ten minute's up the road.Muttleyhttp://www.ebay.com.au/itm/New-20-MHz-Dual-Trace-Oscilloscope-HQ-/260686424575?pt=LH_DefaultDomain_15&hash=item3cb21f29ff#ht_5265wt_1034

author: lowimpedance
author_rank: Super Contributor
timestamp: March 24, 2015, 10:56:29 pm
content: ................clearly needs to cover the cost of the bubble wrap.

author: Muttley Snickers
author_rank: Unknown
timestamp: March 24, 2015, 11:10:48 pm
content: Quote from: lowimpedance on March 24, 2015, 10:56:29 pmAlthough to be fair, thirty buck's world wide is more than reasonable in my opinion.Bugger it, just realised that he is out of stock down the page, 5 available, 18 sold.MuttleyCompared to the above listing these pictured below probably are not such a bad deal after all.

author: flashcoder
author_rank: Newbie
timestamp: August 06, 2021, 10:47:07 pm
content: Did not really want to bring up a new thread on this topic but just recently I had an opportunity find out how reliable is the old TDS210. I had this TV with LED backlight problem, it kicked in for a split second and then turned off. At some point I wanted to see what the LED driver is sending to the MOSFET and but my fairly recent entry level SIGLENT did not show anything on its output. The LED backlight clearly blinks for a short moment every time I turn on the TV so it must be sending something. But the scope refuses to pick it up. I tried many times, went through scope settings to make sure I am not doing something wrong, went for defaults - still no go. So I went to my closet and pulled the good old TDS210 out of the box and bingo - it captures the waveform the first attempt in single mode! Soo.. I am in the market of a new scope. Entry level SIGLENT is crap, even it it has more bells and whistles what is the use of it if you cant rely on it doing its most basic function reliably. I cant even explain why it happens this just crazy. The SIGLENT worked well so far and I never really noticed anything weird. But this test clearly shows it does not work properly.Will I ever get rid of my old TDS210? Naah, never. This is why people love these old scopes - THEY ALWAYS WORK. I am even considering using it as my primary scope, well, at least I will get something better. Definitely no SIGLENT any more they have lost any trust.

author: Hydrawerk
author_rank: Super Contributor
timestamp: August 06, 2021, 10:51:43 pm
content: TDS210 was quite expensive back in the 1997 or so. It was one of the very first portable scopes with no fan.

author: 2N3055
author_rank: Super Contributor
timestamp: August 06, 2021, 11:00:35 pm
content: Quote from: flashcoder on August 06, 2021, 10:47:07 pmUnless Siglent is damaged, I find your story (or shall I say your conclusions) quite hard to believe. By that I don't mean you didn't have problems capturing data, but your conclusion something is wrong with the scope might not be the only conclusion. Could you please elaborate what exactly signal was and how did you setup scopes so one did catch a data and other didn't ..Scopes from Rigol, Siglent, Micsig etc. are not perfect, but basic things like triggering they do flawlessly. So it is either you didn't know how to use it, or scope is damaged, or you caught a rare bug, in which case both many users here and Siglent will like to know. And yes, WHICH entry level Siglent you're have?

author: flashcoder
author_rank: Newbie
timestamp: August 06, 2021, 11:55:42 pm
content: No the SIGLENT is not damaged, it is not much used and even looks brand new, so far it always did what I wanted. Like I said I had no complaints before and I would probably not have any if not this incident. It is SDS1102CML+ model. Yes it is entry level scope but this topic discussion is about the fact that the newer cheaper scopes are always better. And this is clear example that it isnt true. It does not register the impulse no matter what. I did set it to defaults to rule out any setup mistakes but it does not "see" that short impulse. But the old and omg_why_it_is_still_so_expensive TDS210 shows the signal flawlessly. That was my point. I cant trust this Siglent any more. What other stuff it could be not doing correctly? Well obviously this is a simple case but how can I be sure that it always "sees" the stuff that I am trying measure? I might sound like a drama queen and this is not life and death situation but all I am saying it is better to have an older instrument that you can trust instead of having a nice color screen.

author: bdunham7
author_rank: Super Contributor
timestamp: August 07, 2021, 12:05:35 am
content: Quote from: flashcoder on August 06, 2021, 11:55:42 pmYou sound like an inexperienced user. The situations sounds like PEBKAC (user error). How would you go about setting up your SDS1102CML+ to capture the turn-on event?

author: flashcoder
author_rank: Newbie
timestamp: August 07, 2021, 12:13:17 am
content: You mean enable single more, make sure there is no bandwith limit on and set the trigger on the rising edge? Yes I did that. I did the same steps as I did on TDS210 which worked at the first try whereas SIGLENT simply did not capture anything. I tried to see if I can spot an impulse on the screen without triggering but it never showed the impulse..

author: xrunner
author_rank: Super Contributor
timestamp: August 07, 2021, 12:18:41 am
content: Quote from: flashcoder on August 07, 2021, 12:13:17 amI have a TDS210 up on the shelf. If you know what the pulse characteristics are I would have tried to duplicate the triggering here with a pulse grnerator, but I don't have the Siglent model to compare so it wouldn't prove anything. Maybe someone else here can try it ...

author: bdunham7
author_rank: Super Contributor
timestamp: August 07, 2021, 12:27:20 am
content: Quote from: flashcoder on August 07, 2021, 12:13:17 amOK, so what were the characteristics of the impulse as shown by the TDS210? It seems wildly improbable that there is either a bug or single-unit defect in the Siglent that would prevent capturing such a seemingly basic event but not be readily apparent in other cases. There are two additional settings that you should have mentioned in your setup, b/t/w. Actually three, but unless you actively changed something the third should be correct by default.

author: tautech
author_rank: Super Contributor
timestamp: August 07, 2021, 12:35:31 am
content: Quote from: flashcoder on August 06, 2021, 11:55:42 pmBSDid you use Normal or Single triggering ?

author: bdunham7
author_rank: Super Contributor
timestamp: August 07, 2021, 12:43:07 am
content: Quote from: tautech on August 07, 2021, 12:35:31 amWell, actually either of those should work unless the trigger is down in the noise, in which case neither will work. It's the default AUTO setting that would cause trouble.

author: flashcoder
author_rank: Newbie
timestamp: August 07, 2021, 12:44:59 am
content: QuoteWell I was wildly surprised myself. Initially I thought it is the signal hunting glitch that its the triggering that fails, that their advertised "easy signal hunting" feature is the problem but I tried to spot the impulse without any triggering multiple times and I never saw any change on the screen, it just skipped it like its too fast for it to notice. If I understand correctly if the waveform does not "jump up" on the screen then scope simply does not not see it, there is nothing to trigger on. So it means the triggering is not the problem it is the front stage. And what are those other settings I should have mentioned in scope setup? I just gave the basic ones, sure the trigger level is important etc etc but what surprised me is that I never saw the impulse w/o any triggers just by looking at the screen at high frequency and try to spot anything..I might recreate the whole scenario because I did not fix that TV yet I drove it off to my storage maybe will look at it someday again and repeat the measurements. Maybe I am doing something wrong, I am not a very experienced indeed in these type of repairs.If we will find out that it was my mistake then that itslef in an answer why these old TDS210 scopes sell for so much on eBay - because not just EEVBlog experts can operate them but normal people too!

author: bdunham7
author_rank: Super Contributor
timestamp: August 07, 2021, 01:01:18 am
content: Well if you do get the TV back in, post here and we'll get you that capture.It is true to some extent that a scope like the TDS210 is probably more foolproof then the SDS1102CML+, but there should be no issue capturing this signal. To start, you should have a rough estimation of what the signal might look like. You mentioned a brief blink, so an overall event length from tens to hundreds of milliseconds seems likely. Obviously the power-off signal level is zero, lets say the power on level is 10 volts. That's just a guess, if at first you don't succeed, try again. So, as you said, you set the scope for single mode, trigger to rising edge and obviously, volts per division to a reasonable number, probably 5.00V/div. Then, in addition, you have to set the timebase to something on the order of the anticipated signal, so perhaps 10ms/div to start and you have to set the trigger somewhere between zero and the maximum you expect. I would set it at 1 volt or so, but anything high enough to keep noise from triggering it will work. The third thing is that the input should be DC-coupled, not AC.If you set the timebase very fast, you'll likely see nothing. You certainly won't catch or observe a one-time event like that unless you use a very slow sweep or roll mode with peak detect, if the CML+ has it. And when you use single mode, if you leave the trigger near zero, random noise may trigger the capture before the event occurs. I don't have a CML+, but on most scopes there is an indication of whether it is ready (ARMED) or has already triggered (TRIG). You need to make sure it stays armed without triggering until your power-on even occurs. Anyway, better luck next time!b/t/w, I have no idea what "Easy Signal Hunting" is?

author: tautech
author_rank: Super Contributor
timestamp: August 07, 2021, 01:37:40 am
content: One must remember early DSO's emulated CRO performance and particularly phosphor persistence whereas later other tools were added to DSO's to do the same thing....user selectable Persistence and color grading for example.As WFPS rates increased CRO emulation was counterproductive and waveform info pushed to the display became only the real data points and somewhat simple user input required to reliably show glitches, pulses and the like.It's a long time since I had a TDS210 when at the same time a TDS2012B was my main DSO yet of the many dozens of SDS1102CNL and + models sold no one has ever complained they couldn't detect a pulse or glitch.How you understand your DSO and how you apply its feature set is what's important.Quote from: bdunham7 on August 07, 2021, 01:01:18 amMarketing slogan.

author: 2N3055
author_rank: Super Contributor
timestamp: August 07, 2021, 10:19:54 am
content: First make sure you set input channel to DC coupling, and also trigger to DC coupling.When hunting for such, very undefined pulses, a peak detect plus roll (scan) mode is very helpful.Roll (scan) is slow, untriggered mode that basically emulates chart recorder.That, combined with peak detect mode of acquisition, creates a slow scanning graph of voltage that will, despite being slow, capture high peaks in full bandwidth of the scope.Since roll mode is slow, you simply enable it, let it scan, manually create event to measure, and than you have time to quickly stop the scope manually too.Your fast pulse might be a singe vertical line on the screen, but it will be there, and it will have proper amplitude.If needed, now you know how to setup scope vertical sensitivity, and then you set trigger to Edge mode, and set trigger level to somewhere mid way of the signal. You than switch from ROLL mode to normal swept mode, and set some time base that looks logical from what you see on the screen. Keep the peak detect mode still, until you manage to find timebase that shows your signal nicely.You can get pulse captures in Single and Normal trigger mode if triggering is set right. Auto trigger mode is not good because after some timeout it will erase the screen and do capture on it's own if there was no trigger for some time.. Single mode will capture and stop and Normal mode will capture, rearm and wait for next one. If you want to keep just one capture then you use Single, obviously.On scopes that have ETS sample mode (equivalent time sampling), you have to make sure your'e NOT using ETS on pulses. It works on repetitive signals only, and on single pulse you will get nothing on the screen.It is amazing, how very simple scopes like that, that have only few more options than old TDS210, quickly become more complicated to use...I don't have (and never used) that particular Siglent, so I don't know if firmware is clever enough to automatically disable ETS when you enter Single mode.