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Beolover SyncDrive: DC Platter Motor Replacement for Beogram 4002 and 4004 (Type 551x and 552x)

Late Beogram 4002 and the 4004 (Types 551x and 552x), which have DC platter motors instead of the earlier synchronous AC motors usually suff...

Friday, June 6, 2014

Beomaster 8000 Power Supply Restoration - More Dead Caps!

Today, I rebuilt the power supply of the latest Beomaster 8000. Nothing very surprising. Two of the reservoir caps were out of spec. C31 was at about 2000uF instead of 4700uF and it also measured a slight current when hooked up to my bench supply (this was the one that felt slightly warm when I tested the outputs the other day)...C35 was disconnected due to a broken lead, but it also tested 20nF (instead of 10 uF), i.e. it did not really matter whether it was connected or not. Since the Beomaster worked fine even with these caps in place, it appears that they are not essential...but the 5V supply would definitely have shown an out-of-spec ripple. Her are a couple of pics before and after rebuild:

And after:

I also cleaned all the pin headers on the board with a fiberglass pen and then slightly bent the pins alternatingly to increase the contact pressure. 

On to the main reservoir caps!

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