The Beomaster 8000 is on the bench again. After about two weeks of happy service in the living room after 'completing' my restoration, out of a sudden it went into standby. Turned it on again...half an hour later: Standby! Not great. Tried it a few more times....Standby! And again!. I swapped it out with Beomaster 8000-2 (it is like with classic cars...one best has two if one is supposed to run at all times...;-), and opened it up. It turned out that the standby pin (#14 on IC4 - the microprocessor responsible for the radio, volume and startup) occasionally disconnected from the power supply causing the Beomaster to go into standby. This becomes evident by a larger-than-0V voltage (~3.5-4V) at pin 7 on P76 on the microprocessor board (#9). I traced the problem to a bad via on the board. Resoldering the via between P76-7 and pin 14 of the processor solved the problem. Here is a picture:
I resoldered all three vias above the microprocessor (to the right of the C97 label) for good measure. This is done best by simply putting a dab of flux paste on each via, and briefly reheating them with the soldering iron (340C). Use the usual precautions against ESD if you do this in a dry-air environment...the microprocessors are hard to find...;-).
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