You're using the cheapo aliexpress ESR meter that identifies transistors and other components, right?
In case you are talking of the AVR-Transistor-Tester - this is a masterpiece of useful low-cost test equipment😉
AVR Transistortester – Mikrocontroller.net
AVR Transistortester – Mikrocontroller.net
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Hi, Chris!
I measured it a long time ago, and don't remember now. I know it was in the meter documentation and I know that it is somewhere between 70 kHz and 140 kHz. And this is fine.
No, I don't agree. It is definitely suitable for it. Even 50 kHz test frequency gives a possibility to distinguish good caps from bad (twice as smaller than rated 100kHz). If it is near 100 kHz (+-30..40%) - it is fine both for 50/60 Hz power supply units and for high frequency (50kHz-500 kHz) power supply units too. I mean it is good for measuring general-purpose type electrolytes and for Low-ESR type ones.
Ok, if we'll talk about audio devices only then (again) - I would use ESR-meter first because electrolyte caps are well known to die first. And then I'll use all my other tools: signal generator + oscilloscope + spectrum analyzer, RLC-meter, etc. Also, it depends on the audio device age and cap type I would either replace some caps (or most caps) or do only measurements.
The last time I serviced/repaired an audio device - it was quite an old soviet amp (2x50W @ 8R) - I measured many caps with RLC-meter, possibly about 50-70% of them all, just for curiosity and for the experience. But then I replaced them ALL - paper type (these had bad DF and increased capacity too much, as usual. I replaced em with usual PET film), film type (replaced them with smaller size same type PET film, or with large capacity same type film, or used a better film - PP), old ceramic types (I used smaller size through-hole NP0, and a pair of SMD), and of cause - I replaced all electrolytes (I used both polarized and bipolar types). I used mostly bipolar electrolytes in a signal path (they were a great deficit in the Soviet time). I left only two large 15000(?) uF 80V caps in a power supply untouched, they are of a reliable type, and will live a long life.
Then, I replaced all transistors and diodes with actual good ones (ST/Vishay/etc). Checked the resistors (not all, but all feedback circuitry).
When I done with parts, and amplifier started to work fine, I started to check its properties, started to investigate its distortion (preamp modules then output amp). The preamp was fine till this moment (0.002% at rated voltage and load), but the output power amp PCB had too large distortion - 0.02-0.25% depends on a load 4/8 Ohm and an output voltage.
I made some investigation (it took a couple of days or more, up to a week), found a reason for so large distortion with 4 R load, changed a couple of wires onto a PCB, and now it has about 0.010-0.005% THD+N max (at any load, even at 4 Ohm). I don't know if PCB wires were intentionally wired badly by design (to have a lot of even harmonics), or it was just a silly PCB-engineer at a usual soviet plant (I lean towards the second).
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Here is a spectrum at the output of that whole amp with 8R load and 10 VAC, after my service. I don't have a "before-service" picture but it was 20-40 dB worse. I haven't saved it because it was too bad for me.
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No, it is a $30-$40 one, made in Ukraine. I understand what you are talking about, I have one of these magic-multi-part-testers too, but I use it very rarely because I don't need to. Experience + several DMMs + ESR meter + all my other meters and tools (partially DIY) removed the need in that transistor identifier. Now, I have it "just in case".
These transistor identifiers are not of an "in-circuit" type, they need that a part under test was totally unsoldered, which is not convenient. If I unsolder some old part (usually about 40 years old) - it is often more reasonable to replace it with a new modern one.
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mine uses the Atmega chip, yes it is cheap, but it works for me, period....
i never advocated anybody else use it if you are convinced it is trash...
i have 9 other dmm's at my bench....but the esr testers gets called more often specially when stuffing boards...
and ever since i started using the esr meters, i have completed about 4 amps that worked the first time i pugged it in the wall.....
i never advocated anybody else use it if you are convinced it is trash...
i have 9 other dmm's at my bench....but the esr testers gets called more often specially when stuffing boards...
and ever since i started using the esr meters, i have completed about 4 amps that worked the first time i pugged it in the wall.....
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No, I don't say it is a trash. It is not. I only say that I now have more convenient tools. (More convenient for me and for my current experience). But for example, 10 years ago or more I would be happy to have this transistor identifier.
I believe every tool may be useful in experienced hands (and while you don't have something better).
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and it is getting to be a habit now, my latest 300b tube amp build, after i designed the power traffo and built it and used it, i never even bothered to check voltages.....
i know that what i did was right by the sound it made, and my esr tester helped me there...
folks, do not do what i did....
i know that what i did was right by the sound it made, and my esr tester helped me there...
folks, do not do what i did....
Hi.Vishay BC produces many quality parts and capacitors.When i check datasheets of electrolytic capacitors sometimes it writes audio in applications and sometimes do not. I wonder why. For example :
https://www.vishay.com/docs/28345/050-052ped-pw.pdfand this one writes usable for audio in application section
https://www.vishay.com/docs/28346/051053pe.pdfThe both caps seems similar.But what are the differences between them to make 051/053 ones are suitable for audio? Does not 050-052 series work well in audio power supplies? Thanks
https://www.vishay.com/docs/28345/050-052ped-pw.pdfand this one writes usable for audio in application section
https://www.vishay.com/docs/28346/051053pe.pdfThe both caps seems similar.But what are the differences between them to make 051/053 ones are suitable for audio? Does not 050-052 series work well in audio power supplies? Thanks
These BC are a little short sounding in the bass area I found in the few I tried as smoothing cap or local decoupling.
Hey Iggy hows the going ? Many are still caught up in just looking at specs will be difficult for them to accept your comment
Hi.Which BC capacitors have you tested? What is the series numbers? There are many different types of BC capacitors available.I have millions of them in our storehouse but have not made an audio test yet except several ones 😉
Both will work at power supply. If the power supply is a smps, uses the lowest esr of the two. But if you have the choice for smoothing caps after the diodes bridge then long life and higher voltage rating will be more long term reliable.
You do not care about audio marking cause it is not always a proof of better sounding VS a non audio cap. When you have played with plenty brands and model you understand what I mean. Anyway Vishays are solid good caps...I just do not like them but their upper midrange and even so there is better here. Just my opinion though...
You do not care about audio marking cause it is not always a proof of better sounding VS a non audio cap. When you have played with plenty brands and model you understand what I mean. Anyway Vishays are solid good caps...I just do not like them but their upper midrange and even so there is better here. Just my opinion though...
Hi.Yes i know both will work well.We have sold many of them to hundreds of customers.And i also made amps with some of them too.I just wondered if any special reason that they added " for audio" in datasheets of some of them and some not.Regards
... by ears... or by marketing dpt ? 😉
If umut asked and already tested both in his amps I strongly surmise he heard no differences or he would not had asked.
AV is not a little industrial market, so they eventually write it or sometimes even develop a dedicated range as Nichicon, Elna etc. While Philips had AV products they never had dedicated caps for the purpose. Then the become BC and now Vishay BC I tested no subjective sounding difference on these caps. But who knows...if one has million of them in his store it should be worthing to ask to Vishay?
If umut asked and already tested both in his amps I strongly surmise he heard no differences or he would not had asked.
AV is not a little industrial market, so they eventually write it or sometimes even develop a dedicated range as Nichicon, Elna etc. While Philips had AV products they never had dedicated caps for the purpose. Then the become BC and now Vishay BC I tested no subjective sounding difference on these caps. But who knows...if one has million of them in his store it should be worthing to ask to Vishay?
I have used 056 series but it was in the past.Amps were sounding good.
Yes we asked them some questions about other subjects but did not get a satisfying answers.Not detailed answers.Marketing dept answers as you said.They forwarded it to our local seller too and again not satisfying.We will ask about these caps too but i am sure we will get a round answer.
I will test the caps with same capacity and voltage. Maybe can not tell a difference because they seem very similar.Bigger one is longer life one.
Yes we asked them some questions about other subjects but did not get a satisfying answers.Not detailed answers.Marketing dept answers as you said.They forwarded it to our local seller too and again not satisfying.We will ask about these caps too but i am sure we will get a round answer.
I will test the caps with same capacity and voltage. Maybe can not tell a difference because they seem very similar.Bigger one is longer life one.
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