One more test:
Not measure on the resistor 6 legs.
Instead measure ohms the same way you measure bias voltage from pcb pin to L fork. That rules out the possibility of a bad solder joint on the resistor 6.
Not measure on the resistor 6 legs.
Instead measure ohms the same way you measure bias voltage from pcb pin to L fork. That rules out the possibility of a bad solder joint on the resistor 6.
There is another possibility:
Tran 5 could have a partial short, like a built in resistor from drain to source. So all the current would flow there, nothing left for Tran 6.
Could be measured: ohms from pcb pin to Tran 5 middle fork. Amp turned off!
Tran 5 could have a partial short, like a built in resistor from drain to source. So all the current would flow there, nothing left for Tran 6.
Could be measured: ohms from pcb pin to Tran 5 middle fork. Amp turned off!
I replaced all the electronics capacitors on the 2 driver boards to new Nichicon MUSE KZ Series that I bought from good ebay seller (I think) I measured all the capacitors with the Peak Electric ESR70 and they was ok. I also opened the 470uf 50V that bought from him and Nichicon KW 470uf 100V that I bought from Mouser I they look identical inside. I also today checked those capacitors that I pulled out from the amp Nippon capacitors and all the capacitors are in the spec. I wanted to share this information to make sure that it's not (or yes) from those capacitors. The problem is now the as it was before replacing them. Do you think it's better to return those capacitors that removed or to leave those capacitors that I've installed?
Forget the capacitors.
And ohm test on Tran5
Then I think it is time to check Tran 5 and 6 out of circuit.
You could just remove solder from the forks and bend out the legs a little.
Still no need to dismantle the whole thing.
Better do this.
And ohm test on Tran5
Then I think it is time to check Tran 5 and 6 out of circuit.
You could just remove solder from the forks and bend out the legs a little.
Still no need to dismantle the whole thing.
Ok, so check resistor 6 from pcb, not from the legs. And do ohm test on Tran 5 like described above.
This for Tran 6 (L) pin hot to the middle. It's 65Kohm. I think I need to give the amp more time to be completely discharged. The value becomes lower and lower.
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Ok, no resistance inside Tran 5 and the 0.22 ohm of Tran 6 is ok measured from the pcb.
Gate voltage of Tran 6 is ok ? 2 V around ? pin to R
Gate voltage of Tran 6 is ok ? 2 V around ? pin to R
