There is something has seemed odd but I didn't want to ask you to recheck all of the voltages. The emitter of that transistors should read 0.00v since it's directly connected to ground. The small errors in voltage could be critical in troubleshooting because the threshold voltage for the transistors is only about 0.5v. Why to you read about 0.5v on the points that should essentially have no voltage on them?
I am not sure, are you asking me? I dont know why something directly connected to ground would have voltage.
Q3 has been replaced twice so I doubt its that but Q4, Q5, Q6 could be defective or leaky I suppose. I have not found any burned traces so far.
Maybe something is backfeeding those transistors voltage???
Q3 has been replaced twice so I doubt its that but Q4, Q5, Q6 could be defective or leaky I suppose. I have not found any burned traces so far.
Maybe something is backfeeding those transistors voltage???
What is the resistance between pin 7 of the 494/7500 and the point where you had the black probe?
What point did you have the black probe on when you posted the voltages previously?
What point did you have the black probe on when you posted the voltages previously?
The resistance is 000.1 to 000.3 ohms pretty steady sometimes jumps around a bit.
I was using the amps ground terminal for the black probe while measuring the transistors.
Power it up again. Place the black probe in the amp ground. What is the DC voltage on pin 7 of the 494?
What is the DC voltage on the emitter of Q3?
They should both be essentially 0v (down to a few millivolts) and should be the same.
What is the DC voltage on the emitter of Q3?
They should both be essentially 0v (down to a few millivolts) and should be the same.
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