I noticed that my 390 receiver has maybe some capacitor issue in the audio board (i suppose).
Unnoticeable while connected to an antenna, when the receiver is disconnected from the ant, i ear some (frrr frr frrrrr i cannot really write the sound
) from the speaker not continously but randomly present.
If i pickup the audio from the diode output, the problem is not there.
So it's probably a condenser leaking in the audio amplifier stage.
I have never dismantled a 390 and i need some help of the best and unpainful way to reach the audio amp ad check condensers on it.
thank you.