Progress, I think - the machine isn't imagining the OFF command, it really accumulates the "run-off" signal voltage at the test point over C33 from pulses coming from nowhere, while the ruler sensor is in the dark. But not always :-/ (Wish the nice folks at B&O had designed the machine so that I could probe with the oscilloscope while

Thanks, tried that. Didn't help :-/ (actually didn't bend them as they're on plastic holders, I just adjusted the ruler as close to the sensor as possible) Ummh... IR? We are talking about the same 6000 (a.k.a 4002), right? This has an incandescent light and I guess an LDR... The analogue control logic is diabolical and defies human mind

After some experimenting, I noticed that the problematic positions aren't random at all any more. They are invariably right after start, even so that the arm doesn't have time to lower at the 45 rpm landing zone ...i.e exactly where the wide black stripes are located on the position encoder bar, or whatever it's called. I removed it temporarily

I finally got around to looking into this. I replaced four caps on the capstan board (including the tiny 3u3, I didn't remember that it wasn't on your replacement list) and now the machine works just fine (everything l that I can check without a B&O tv, that is) The solderings under the caps were really ugly, I had a hard time getting them

Gee. Now I've replaced the two large power supply caps, as well as every single electrolytic (including tantalums) on the main board and the one on the sled. The machine still makes spontaneous automatic stops at seemingly random positions, though perhaps not so often. Anyone care to comment on what to check next?

The microswitch itself could be at fault. I think it's safe to test tripping it manually, it becomes visible when the sled is around halfway through its travel. The arm should raise and the unit shut down. Anyway, the power supply is controlled electronically, and not directly by the switch. You might have a bad solder / diode / transistor somewhere

By the looks of it, it seems that it's possible to switch any number of speaker pairs "on" at the same time (and the "protection circuit" just limits how many). If that happens, you'll be effectively connecting two amps in parallel. So I don't think it's a good idea... -mika

OK, now I've been inside the deck, and cleaned and lubricated the two fixed tracks of the transport, as well as the worm track. This actually helped a lot, now I've been able to play two consecutive record sides without the machine cutting out, but the problem still remains. I noticed that the tone arm "leads" a bit while playing,

fastone: I have a Beogram 5500 that needs an RIAA preamp board so it can be plugged into a 6500 receiver. The amp board from a Beogram 6500 would work but does any one where one is for sale or a similar substitute? I was adviced here earlier, that the option board for the Beomaster 6500 would still be available from the dealer, and not too expensive

beorebels: It was an problem in the sliding mechanism of the tone arm; the b&o technicans have cleaned this mechanism and they did an relubrication of the sliding mechansim. Thanks, lubrication will be one of the first things I'll check (I've learned this with about every single one of old B&O gear I've looked into...). Nevertheless