I took my working 3566 and replaced all of the capacitors and the 1 & 10 ohm resistors with like for like replacements. (old caps were starting to leak and R765 & R760 were a tad cooked and measured around 1Mohm)
Pre test run checks indicates that the resistance between BATT and GND is 3.7ohms which is definitely not right. I've taken it back to bits and checked for shorts and not found any. The caps I put in were all good from what I could tell as were all the resistors. I've tested it on a bench supply with current limiting and as the current/voltage rose I got the expected got very toasty resistors R765, R760 & R773, but no catastrophes.
Any ideas what I have managed to do? I did the same work bar the resistors on my 3553 at the same time and that amp seems to be ok.
Images for reference Dale CPF 1% 1 & 10 ohm used to replace originals
Main bulk changed for panasonic FC/FM/FR.
Pre test run checks indicates that the resistance between BATT and GND is 3.7ohms which is definitely not right. I've taken it back to bits and checked for shorts and not found any. The caps I put in were all good from what I could tell as were all the resistors. I've tested it on a bench supply with current limiting and as the current/voltage rose I got the expected got very toasty resistors R765, R760 & R773, but no catastrophes.
Any ideas what I have managed to do? I did the same work bar the resistors on my 3553 at the same time and that amp seems to be ok.
Images for reference Dale CPF 1% 1 & 10 ohm used to replace originals
An externally hosted image should be here but it was not working when we last tested it.
Main bulk changed for panasonic FC/FM/FR.
An externally hosted image should be here but it was not working when we last tested it.
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