Ls,
Not long ago I replaced the 8v bulb that sits behind the meters in this Amplifier.
It started failing, but would relight on light tapping.
Changing a bulb is about as good as I get with electronics, but I thought I'd try some quick metering before I turned to the AudioKarma Oracle.
So the bulb looks silvery, I think its burned out.
Testing the circuit with the "beep" mode (don't even know what its officially called
) circuit tester?
It beeps if test both feet from the lamp itself, but its still connected to the power supply wires, I thought that would test if the lamps insides were burned through. But I don't know if it would be connected through another route. I can't really read schematics.
So I tested the two wires running through the lamp on the side of the power transformer for voltage.
It shows a voltage of about 20V to -20V looping back and forth.
I don't understand that at all because the lamp is 8V.
Can someone explain that to me?
Perhaps that because there is no load on it?
Is there perhaps a Cap that is faulty?
I will include the schematics.
The entire service manual can be found at: https://www.audioservicemanuals.com/s/sansui/sansui-a40/127565-sansui-a40-service-manual
Highest regards,
Mac
Not long ago I replaced the 8v bulb that sits behind the meters in this Amplifier.
It started failing, but would relight on light tapping.
Changing a bulb is about as good as I get with electronics, but I thought I'd try some quick metering before I turned to the AudioKarma Oracle.
So the bulb looks silvery, I think its burned out.
Testing the circuit with the "beep" mode (don't even know what its officially called
) circuit tester?It beeps if test both feet from the lamp itself, but its still connected to the power supply wires, I thought that would test if the lamps insides were burned through. But I don't know if it would be connected through another route. I can't really read schematics.
So I tested the two wires running through the lamp on the side of the power transformer for voltage.
It shows a voltage of about 20V to -20V looping back and forth.
I don't understand that at all because the lamp is 8V.
Can someone explain that to me?
Perhaps that because there is no load on it?
Is there perhaps a Cap that is faulty?
I will include the schematics.
The entire service manual can be found at: https://www.audioservicemanuals.com/s/sansui/sansui-a40/127565-sansui-a40-service-manual
Highest regards,
Mac
