B&O Beogram 8002: Help Needed with Unusual Operation

[Marcham93]

Hey, all.

I'm having trouble with a Beogram 8002 that I picked up and was hoping someone could help. I've done some work on the unit, including recapping it, so I'll fast forward to the current state of affairs. Right now, the two primary issues are that the platter turns constantly, even when in standby, and four red dots appear on the LCD at all times.

Taking a look at the board, the +15V and +5V rails look good, but there is a problem with the -15V rail. I've taken a few readings in the power supply region, and the transistors seem to test fine with my little component tester, so I can't seem to find the issue. I'm hoping once the -15V rail gets sorted out, everything will improve with it.

Any help would be greatly appreciated.

Thanks, all.

 

[Marcham93]

Just bumping and popping in with an update.

Still at the same point but been poking around the board and reading voltages.

I noticed that the main chip’s voltage on pin #38 (on/off) swaps between 0V and 2.5V. However, the chip seems to be getting its primary 5V at pin #30 without issue, so could the chip be the issue in any way? I tried reseating it, but it did not change.

Poking around TR19 and TR21 trying to figure out why there is still no -15V signal. I feel that’s the heart of the issue.

Thanks, all.