Punch 601s

[Hexhclass]

No audio

 

[Perry Babin]

Black probe on ground, DCV on each end of R37 with pin 14 lifted?

 

[Hexhclass]

0.032v

20.58v

 

[Perry Babin]

Pull C18. Does the voltage on the 0v end of that resistor go to near 20v?

 

[Hexhclass]

Voltage remain the same.

 

[Perry Babin]

Pull R37 and check it out of the circuit.

 

[Hexhclass]

10k out of circuit

 

[Perry Babin]

Lift Q10 again. Does that allow it to pull up to the 20v?

 

[Hexhclass]

Measure voltage where after pulling the transistor?

Leave the cap out still?

 

[Perry Babin]

On each end of R37. It needs to pull the base of Q10 up to drive Q11 on which drives the transistors in the tail of the differential amplifiers (in each channel) on.

 

[Hexhclass]

20.59v 0.030

 

[Perry Babin]

Is pin 14 still out of the circuit?

 

[Hexhclass]

Yes,the cap is also out

 

[Perry Babin]

What else is connected to the points connected to the base of Q10, pin 14 of the 339 and the positive terminal of the cap that could be preventing R37 from pulling up?

Do you have another 10k resistor to install in place of R37?