Re: Tek blue paint available
I heard from Susan last night and apparently there are still 5 cans of paint available.
Jim
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On Mon, Sep 16, 2024 at 12:37 AM, Jared Cabot wrote:
Which group is that?
The search term "ESR" + "TESTER" got ~ 1 million hits, averaged over different search engines. IMO... I do my part to keep OT posting as low as possible. Some people's posts, on other forums... their content on YouTube... shows there is plenty of information about ESR... in all respects. -- Roy Thistle
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Hi Keith, all,
Indeed it is the RIFA cap issue in my 2465 as well. I have a few thoughts about this, and Keith I feel your pain. I was responsible for 20+ Studers of A80 (QC-0.150"/?"/1"/2") and A820 (?"/1") vintage, all with RIFAs all over the place, but the only ones I had fail are the ones exposed to HV/Mains AC. I am postulating it is the dielectric dissipation which heats and slowly degrades to the point where it fails. It may not be necessary to replace the ones in the control cards, unless you are interested in prophylaxis or really bored......just my 2 cents worth.
Another thought I had about the failed resistors in series with the mains EMI filter RIFAs: the original 30 and 68 ohms 1/2 watt resistors were carbon composition resistors, which makes sense given those types are non-inductive. Mouser/Digikey/Newark(Farnell) all have discontinued that type for the most part, all those vendors had in those values were wirewound or 1/4 W metal film, all inductive but I was able to find old carbon IRC ones on eBay. Given they are in an EMI filter role it could potentially make a difference to the filter shape. Probably not a big deal, just a thought.
Cheers & 73,
Howie / WA4PSC
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It's not only the 2x68nF on the A2.
On the A3, you'll find another 4 of these to be replaced.
See the overhaul here:
They're all included in my updated overhaul kit.
I do not sell on Ebay anymore.
Menahem Yachad
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There are RIFA condensers in the power supply on the primary side of the transformer as well. Replace them. I used 630V film types and the X1 types to replace them.
Mark
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My 2445B blew the RIFA caps exactly as you described. Good news is that this is a simple fix. Replace Rifa caps on the AC line input filter. Clean up the mess they left. Search the forum. It has been explained and explored in depth many many times. 2445, 2465, etc. They all have it.
If you think you have it bad with a couple of these things, I feel your pain. I'm working on a Studer A80 right now. The motor control cards are COVERED with Rifa caps of the type that fail. I have to replace them all. I think they are on about ten different plug in card assemblies.
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Tek A5 from Isle of Guernsey issue
I recently received a 2465B, s/n 126xxx, from Isle of Guernsey in which the A5 had Rev -04 firmware.
When I update the firmware to a higher Rev (I tried 06, 08, 11) there is strangeness in the readouts.
Lots of extra characters and garbage characters all over the screen.
It's all readout related because if I turn off the readouts it disappears.
Also, when I put Rev 04 back it behaves normally.
It tells me these Guernsey A5 may be slightly different from the Beaverton, USA A5s (B0xxxxx).
I know this is an unusual issue and the solution is to use Rev -04 firmware, but Rev -11 has some nice features and bug fixes.
Has anyone come across this issue?
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And amount of next year average rain for specific location...
Titi
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Howie usual for the VDE caps to burn up or explode on a 240V mains but seldom on 120V.
No overheating as the event is rapid and the caps are inside the EMI / IEC modules.
Also check the LV PSU board for blowing rectifiers and lyrics as well as tantalum caps.
See th¨¦ EEV blog 75 pages on 2465B teardown.
Bon chance
Jon
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On Tue, Sep 17, 2024 at 07:48 AM, Howard Hoyt wrote:
s? I plan to pull the AC input module out and check it later, but for now I am
baffled.
I had similar in my HP 8904A: it was (probably RIFA) cap in line filter, integrated inside C14 mains socket.
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Hi all,
On the heels of success fixing our 2712 (thanks again, Jaap!) I was doing some digital circuit design using all four channels of the 2465 (although I doubt this fact played any role in the failure) and all of a sudden I heard a sound like an electrolytic cap venting and smoke poured out of the back of the scope, propelled by the fan.
Being very familiar with it after fixing lightning damage seven years ago I immediately pulled it apart, hoping to find a still-smoking part...and I cannot find anything visible..no cap vent residue, no overheated parts. I measured many (but not all yet) electrolytics and they measured in spec with low D and ESR. All the power transistors in the supply measured good...what the heck was the noise and smoke?
I had read about the X and Y caps in the AC input filter failing, but mine was cold to the touch making me doubt any heat could have evolved from any internal components. Has anyone had this experience with any of the 24xx series scopes? I plan to pull the AC input module out and check it later, but for now I am baffled.
Thanks in advance for any clues!
Cheers & 73,
Howie / WA4PSC
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Hi all,
I want to inform the group that Japp is a genius...well, he understands the 2712 as if he had designed it! His experience with his (and other) 271x SA failures was exactly what mine experienced. I replaced some very hard to get electrolytics which had severely degraded in the 1st LO Buffer and 1st LO Interface Board and after re-normalizations the 2712 passes all internal tests and is working as it should.
Thank you Jaap!!! What a resource for this group!
Cheers & 73,
Howie / WA4PSC
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I actually forgot I have a DE-5000 lol. I had to look it up and it recognized it. That is what I use at home. In the lab I use the Reed R5001. Both are great.
Regarding utilizing social media, perhaps it is a generational thing. I'm making an assumption here, but I'd wager I'm probably younger than most in this group. Dave Jones and the EEVBlog were some of my first resources for getting into electronics. There are a lot of great EE YouTubers. But yes, just like anything on the internet, you have to be mindful of your sources and cross-reference.
-Frank
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This is certainly beating a dead horse ? by now...
I have the DER-EE DE-5000. It seemed really cool, but I've never needed to reach for it, and it's collecting dust right now.
I do lots of repairs using the GME 236, a copy of the CapAnalyzer 88A. The GME works very well in analyzing electrolytic ESR, likely Tantalum as well. It's usually the lower voltage radial caps that more often fail, especially on aged equipment with high hours on it.
Some models of gear are unlucky and will more often need a full recap, others aren't so bad. One must be careful with YouTube video content and social media. They can be a replacement for critical thinking in many cases nowdays
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If it helps further, there is also an old school method to measure ESR quite accurately using a known series sense resistor and a decent 5.5 or 6.5 digit DVM that can measure AC Vrms voltage up to about 100kHz. By measuring the voltages accurately around the sense resistor it is possible to calculate the capacitance and ESR of the capacitor at various frequencies up to about 100kHz. For critical testing of small, low ESR caps I'd expect this old method to beat modern LCR/ESR meters like the DE-5000. However, it is quite a clunky and slow method. I semi automated it using GPIB and a Windows app written in VB. Prior to this I did it using Excel or Quick Basic.
I've also used the Analog Discovery 2 to measure ESR with great results. It gives a swept result for ESR and capacitance from (say) 10Hz to well over 100kHz if required. For rapid testing, it is going to be difficult to beat the convenience of modern meters like the DE-5000 though. I'm quite tempted to buy one but I'll probably stick with the AD2 for a while longer. I rarely use the AC DVM method these days even though it can be very accurate and it also allows an external dc bias to be added to the capacitor if required. This can be quite educational when measuring small SMD class 2 ceramic capacitors where the capacitance changes a lot with dc bias.
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This is a good point actually. I learned a few things about ESR in this thread or brushed up on some concepts I hadn't considered in a while. I bet the OP is thinking "alls I wanted was an ESR meter recommendation!" lol.
-Frank
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This is pretty much my train of thought on the subject as well. Look at all the info that is horse traded back and forth in such a thread. Even some of the experienced guys might learn a new tidbit here and there. If we cut every semi-related subject out there will end up being very little traffic and an extinct group before long.--EricSent from my Galaxy
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-------- Original message --------From: "Sigur?ur ?sgeirsson via groups.io" <siggi@...> Date: 9/16/24 4:10 PM (GMT-06:00) To: [email protected] Subject: Re: [TekScopes] ESR tester advice On Sat, Sep 14, 2024 at 5:53?PM Roy Thistle via groups.io <roy.thistle@...> wrote:> And IMO... it's a kind of spamming.> Especially since there is already a lot of 'talk' about these in previous> posts.> And extra especially because there is a whole groups.io group dedicated> to ESR testers.>Imma going to respectfully disagree with your point of view here. Whileit's true that it's perhaps redundant - in terms of the raw theory ofinformation - to rehash this question, it has significant value in morehuman, social terms.IMHO some of the most rewarding threads on this forum start with "I boughtthis very cool, curious thing. Is it broken, how do I point it?", followedby some edumacation from "those who know".If the only topics we ever discuss in this forum are the nitty-gritty ofthe most esoteric Tek test equipment issues, and if anyone asking a n00bquestion is immediately burned to a nub, then ultimately this group willweed down to only those people who have the wherewithal to not as n00bquestions. IMHO that'd be a net loss to the community of test gear nerdsand this forum - the bug is really easy to catch, but equally easy to"cure".Also, nobody in this day and age cares about "bandwidth" for an emailthread, and if YOU don't care for the question or the subject, then mutethe thread. We have technology well beyond the 80s that will do it in asingle keystroke, learn it!
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On Mon, Sep 16, 2024 at 11:07 AM, Frank Mashockie wrote:
IMSAI guy puts out great content whether he likes Tek scopes or not. I'm not
sure what your point is.
Okay, fair enough... one man's beauty, is another's excuse for another drink. My point, is all and only... and just my opinion...there is no implication on general value, if someone prefers chocolate over vanilla? But, I'm sort of on the record here, about, my opinion of YouTube content creators in general... at least at the moment. Agreed. I'd say... the basement floor here isn't in danger of shifting upwards. But the acquisition wasn't motivated by a yearning to 'grow up' to be just like The Guy. I'm not saying that anyone else's was... or wasn't... I'm just opining. Which... IMO...is what forums are for, when matters of fact, are not in dispute. -- Roy Thistle
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On Sat, Sep 14, 2024 at 5:53?PM Roy Thistle via groups.io <roy.thistle= [email protected]> wrote: And IMO... it's a kind of spamming.
Especially since there is already a lot of 'talk' about these in previous
posts.
And extra especially because there is a whole groups.io group dedicated
to ESR testers.
Imma going to respectfully disagree with your point of view here. While it's true that it's perhaps redundant - in terms of the raw theory of information - to rehash this question, it has significant value in more human, social terms. IMHO some of the most rewarding threads on this forum start with "I bought this very cool, curious thing. Is it broken, how do I point it?", followed by some edumacation from "those who know". If the only topics we ever discuss in this forum are the nitty-gritty of the most esoteric Tek test equipment issues, and if anyone asking a n00b question is immediately burned to a nub, then ultimately this group will weed down to only those people who have the wherewithal to not as n00b questions. IMHO that'd be a net loss to the community of test gear nerds and this forum - the bug is really easy to catch, but equally easy to "cure". Also, nobody in this day and age cares about "bandwidth" for an email thread, and if YOU don't care for the question or the subject, then mute the thread. We have technology well beyond the 80s that will do it in a single keystroke, learn it!
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Bonsoir, ESR causes power dissipation, I ripple RMS exp 2 * ESR.
The internal electrolyte hot spot temperature is raised by the dissipated power, so life is shortened and thermal runaway is possible.
Thus the ESR measurement is normal at two ripple frequencies
2X mains for FW rectifiers, 100 or 120 Hz
SMPS switch frequency, usually between 20....200 kHz
The rated temperatures ( 85, 105, 135 degrees C) of lytic is for a 2000 hrs service at rated ripple currents and ambient surface temperatures.
After 2000 hrs th¨¦ ESR Can increase and capacity decrease by 20-50%.
Hope that this is of interest
Enjoy,
Jon
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Jean-Paul
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Frank Mashockie