Amp powers up but no output .
I was checking for regulated voltages and on 1 opamp I bet the following voltages
NJM4556
Pin 1:21.35
Pin 2:12.79
Pin 3:12.79
Pin 4:12.62
Pin 5:0.02
Pin 6:12.64
Pin 7:12.78
Pin 8:12.78
Pin 9:21.53
Is this normal for these amps?
I was checking for regulated voltages and on 1 opamp I bet the following voltages
NJM4556
Pin 1:21.35
Pin 2:12.79
Pin 3:12.79
Pin 4:12.62
Pin 5:0.02
Pin 6:12.64
Pin 7:12.78
Pin 8:12.78
Pin 9:21.53
Is this normal for these amps?
Attachments
It looks like it may have a shorted transformer. What's the DC voltage on the RCA shields and on the negative speaker terminals?
If you still have the 120v incandescent lamp, connect it to the primary ground terminal and touch it to the negative speaker terminals. Does that drain off the DC or does it essentially remain the same?
What was the 12v power supply voltage when you read the 12.79v?
What was the 12v power supply voltage when you read the 12.79v?
Power supply voltage is at 13.88 volts .
If I use primary ground and connect the light bulb to the negative speaker terminal I still get 2.56 volts on the negative speaker terminal .
The relay won’t engage until I plug the rca jacks in or out the light bulb between primary ground and the negative speaker Terminal
If I use primary ground and connect the light bulb to the negative speaker terminal I still get 2.56 volts on the negative speaker terminal .
The relay won’t engage until I plug the rca jacks in or out the light bulb between primary ground and the negative speaker Terminal
I will check .
First I gotta find out what they are using for the regulators and where they are in the board
First I gotta find out what they are using for the regulators and where they are in the board
That's an inductor and should read approximately a dead short.
Measure the resistance from pin 5 of the 4556 to ground.
Measure the resistance from pin 5 of the 4556 to ground.
Edit to #9
Check for resistance from both primary and secondary grounds (negative speaker terminals).
If you find a short, look for a shorted Zener.
Check for resistance from both primary and secondary grounds (negative speaker terminals).
If you find a short, look for a shorted Zener.
Are you sure that you read megaohms from pin 5 of the op-amp to the primary and secondary (- sp terminals) grounds?