Uploaded November 2017 | Updated September 2026, 1 week ago
FM tuner was not working. I was able to work on this problem for a few minutes at a time before I finally really sat down to work on it The first things I did was check for power supply voltage to the tuner section (not shown on video) and used the signal tracer (Sansei 6100) with built-in speaker to see if any signal came out of the tuner section. There was no hiss heard through the loudspeaker of the tracer, so I suspected the problem was not in the RF section. I then fed a modulated (400 Hz) 10.7 MHz signal to the output pin of the IF amplifier IC; a tone could be heard from a loudspeaker which was now hooked up to the speaker terminals of the receiver. I then fed the same signal to the input of the IC; nothing could be heard. The voltage at the VCC pin to the IC was checked; this voltage was very low. The resistor between this pin and the actual VCC supply was found to be defective.
FM tuner was not working. I was able to work on this problem for a few minutes at a time before I finally really sat down to work on it The first things I did was check for power supply voltage to the tuner section (not shown on video) and used the signal tracer (Sansei 6100) with built-in speaker to see if any signal came out of the tuner section. There was no hiss heard through the loudspeaker of the tracer, so I suspected the problem was not in the RF section. I then fed a modulated (400 Hz) 10.7 MHz signal to the output pin of the IF amplifier IC; a tone could be heard from a loudspeaker which was now hooked up to the speaker terminals of the receiver. I then fed the same signal to the input of the IC; nothing could be heard. The voltage at the VCC pin to the IC was checked; this voltage was very low. The resistor between this pin and the actual VCC supply was found to be defective.
