Comet
Williams, 1985
Sorcerer
Williams, 1985
Space Shuttle
Williams, 1984Hello. On my space shuttle, the U47 amp for sound on the heat sink gets very hot in a very short time. It has been replaced and I used thermo compound between it and the heat sink. CPU board is on the bench with a pc power supply providing 5v and +12 volts. What would be causing the amp chip to run so hot?
Thanks.
I believe it was a TDA 2002. No soldier bridges. The voltage is good. I think I replaced c25. Perhaps r72/r73 need looked at as well as the other axial caps in the sound circuit? Maybe C28 and C29 are shorted?
Where did the TDA2002 come from?
What type of cap at C25?
Nothing is plugged onto J15?
R72/R73 unlikely but weirder things have happened.
C26 would short out +12 supply and cut power to U47 - not this one.
C29 being shorted could introduce a DC offset into the amp. Yes, that can be bad but still not likely.
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