The below pins are fluctuating while all other pins have steady voltages, and pin 3 is still lifted during this test.
Also those voltages would drop lower the longer power was applied. As an example the first minute voltages bounced from 2.5-5v, after five minutes the voltages would bounce from 0.5v-2v, and after 10-ish minutes it was bouncing from 0.2-1v. No components seemed to be getting hot either. Should I order another IC?
Pin 8
pin 13
pin 16
Also those voltages would drop lower the longer power was applied. As an example the first minute voltages bounced from 2.5-5v, after five minutes the voltages would bounce from 0.5v-2v, and after 10-ish minutes it was bouncing from 0.2-1v. No components seemed to be getting hot either. Should I order another IC?
Pin 8
pin 13
pin 16
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This leads back to U13 the LM339 chip with outputs 1,2, and 13 as they are connected to where this fluctuation is originating from correct?
Pin 1: 0.5-2.5 (output 1)
Pin 2: 0.5-2.5 (output 2)
Pin 3: 12.92 (vcc)
Pin 4: 9.85-10.5 (input 1-)
Pin 5: 10.5-11.3 (input 1+)
Pin 6: 5.2-6 (input 2-)
Pin 7: 4.98 (input 2+)
Pin 8: 0.02 (not used?)
Pin 9: 0.03 (not used?)
Pin 10: 4.98 (input 4-)
Pin 11: 11-11.7 (input 4+)
Pin 12: 0 (ground)
Pin 13: 0.5-2.5 (output 4)
Pin 14: 0 (not used?)
Pin 1: 0.5-2.5 (output 1)
Pin 2: 0.5-2.5 (output 2)
Pin 3: 12.92 (vcc)
Pin 4: 9.85-10.5 (input 1-)
Pin 5: 10.5-11.3 (input 1+)
Pin 6: 5.2-6 (input 2-)
Pin 7: 4.98 (input 2+)
Pin 8: 0.02 (not used?)
Pin 9: 0.03 (not used?)
Pin 10: 4.98 (input 4-)
Pin 11: 11-11.7 (input 4+)
Pin 12: 0 (ground)
Pin 13: 0.5-2.5 (output 4)
Pin 14: 0 (not used?)
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no clue to be honest. Pin 3 of U13 LM399 is the VCC pin, and not directly impacted by those resistors as they are part of 5 and 11 of the LM399? I don't think I have enough knowledge to answer that question correctly. I also lost the 2.5-5v at the gate leg for some reason. it varies between 0.3-0.75v now it seems. Pin 3 of the SG3526 is still lifted as well.
Power supply is an Aston RS-50A this exact one in the link below:
Astron Power Supplies RS-50A - Free Shipping on Most Orders Over $99 at DX Engineering
Power supply is an Aston RS-50A this exact one in the link below:
Astron Power Supplies RS-50A - Free Shipping on Most Orders Over $99 at DX Engineering
R65 does have a solid 13.65v on one side, but fluctuating voltage on the other. I think I'm going to put this back on the shelf as I feel I've spent too much of your time as well as my own time attempting to fix something that I discovered I will not be able to fix. So thank you for your attempted help to fix this amplifier Perry I appreciate it.
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