Yo Carlos, check your mute circuut, see the output schematic :
(Test by remove the diode)

Hi Cees.

Thanks for the reply, but the problem wasn't in the mute circuit.

Let me explain:

After disconnecting the diode, I tested the tuner on the workbench, and it was working. I reconnected the diode, and it was working fine.
I put the tuner back in the music center, and it started malfunctioning again. (The problem was there.)
I checked everything and discovered that the antenna cable was broken near the connector.
This problem must have happened when I moved the music center during cleaning...

Best regards,
Carlos

I repaired my tuner which had a broken zener diode in the power supply.

It worked very well until now, but another problem has appeared:

The output level is very low, and it's almost inaudible.

I tested the amplifier and it's okay.

I checked the power supply and it's fine.

My suspicion falls on the output integrated circuit, UPC 1235C, but I would like to have some more certainty and for that I would like to know what voltages are present at its terminals.

In the diagram I have, I can't see these voltages clearly.

My question is:
Does anyone have the original schematic, where these values ​​are perfectly visible?

Can you tell me what the voltages are at each pin?

Thank you.
Carlos

Yes I have, send me a pm and you get it.
Greetings, Ben

Many thanks Ben.

PM sent.

Best regards,
Carlos

Does anyone have the service manual for the Akai AT-A102 tuner?

I need it to try to repair my tuner.

Many thanks,

Carlos