For information only.
Picked up this set a few days ago with symptons no sound. Opened up the back to take some measurements and the sound returned. No amount of flexing and tapping the board would stop the sound.
Main Board T.MSD306.68A 12023
After running for about 4 hours the sound dropped out again and again no amount of tapping, flexing or cooling around the audio amp (R2A15122FP) would bring the sound back.
Out with the meter. Supply voltages on VD1 (Pins 13 & 14) and VD2 (Pins 37 & 38) were both present at 25V.
Checking the mute input (Pin 34) the voltage change on the pin when mute was selected on remote was 3.4V to 2.9V.
Followed the mute control line back to the two smd transistor (H1A & H2A) close to the audio amplifier "Power In" connector.
Resoldered the two smd transistors and problem now appears to be solved.
Picked up this set a few days ago with symptons no sound. Opened up the back to take some measurements and the sound returned. No amount of flexing and tapping the board would stop the sound.
Main Board T.MSD306.68A 12023
After running for about 4 hours the sound dropped out again and again no amount of tapping, flexing or cooling around the audio amp (R2A15122FP) would bring the sound back.
Out with the meter. Supply voltages on VD1 (Pins 13 & 14) and VD2 (Pins 37 & 38) were both present at 25V.
Checking the mute input (Pin 34) the voltage change on the pin when mute was selected on remote was 3.4V to 2.9V.
Followed the mute control line back to the two smd transistor (H1A & H2A) close to the audio amplifier "Power In" connector.
Resoldered the two smd transistors and problem now appears to be solved.
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