Thank you again .
R108 is 25 turns pot. I noticed the good one has dc offset about 300mV at mid span POT but the Bad one is start at -3.5V. It is too far for adjusting.
How can I check input mosfets by not take them out?
And Is it possible that Q103 be a malfunction part?
R108 is 25 turns pot. I noticed the good one has dc offset about 300mV at mid span POT but the Bad one is start at -3.5V. It is too far for adjusting.
How can I check input mosfets by not take them out?
And Is it possible that Q103 be a malfunction part?
Last edited:
How did you check? What matching criteria?
By using below diagram. They are very close matched group, as remember ,less than 0.02V.
Is it okay for this job ?
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Hi Zen Mod
After replace 3rd input mosfet set I got it.
Now Happy with new amp.
Thank you very much for your nice support. I almost gave up when changed second input mosfet.
This time I found PCB spoil out then I fixed. It may be damaged since replace first time.
thanks for everyone who advised in this post.
and also be grateful to Mr pass for honorable amps but DIY can affordable.
After replace 3rd input mosfet set I got it.
Now Happy with new amp.
Thank you very much for your nice support. I almost gave up when changed second input mosfet.
This time I found PCB spoil out then I fixed. It may be damaged since replace first time.
thanks for everyone who advised in this post.
and also be grateful to Mr pass for honorable amps but DIY can affordable.
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