Bang @ Olufsen Beogram service help needed

[[email protected]]

Hi all,
I am repairing a B&O Beogram player. I have repaired a good number of
players but this one is so far from the common cdp building methods
that I have problems with it.
The problem of the player is that it spins up the disc (very fast) but
doesn't read. Play simply doesn't start and the display reads 0000.
Seeing that the cd spins I guess the FOK signal is present. Can anybody
tell me how I can go to some kind of a service mode with the player?
Or, does anybody have the service manual? Any kind of help is
appreciated.
I have read somewhere that this player can very easily have connection
problems at its lower board, and the clock IC gets defect easily. I'll
check these, though I guess it wouldn't do anything without the clock
signal.
I cannot find any test points, that also can be a problem later. I
don't know where the RF, TE and FE can be monitored (though I'm not
there yet anyway).
Thanks,
m127

 

[Mark D. Zacharias]

Hi all,
I am repairing a B&O Beogram player. I have repaired a good number of
players but this one is so far from the common cdp building methods
that I have problems with it.
The problem of the player is that it spins up the disc (very fast) but
doesn't read. Play simply doesn't start and the display reads 0000.
Seeing that the cd spins I guess the FOK signal is present. Can
anybody tell me how I can go to some kind of a service mode with the
player? Or, does anybody have the service manual? Any kind of help is
appreciated.
I have read somewhere that this player can very easily have connection
problems at its lower board, and the clock IC gets defect easily. I'll
check these, though I guess it wouldn't do anything without the clock
signal.
I cannot find any test points, that also can be a problem later. I
don't know where the RF, TE and FE can be monitored (though I'm not
there yet anyway).
Thanks,
m127

I have heard that some B&O models suffer from bad feedthrough (solder)
connections on the CD process (servo etc) board. This would be a Philips
board, lots of copper plating visible.


Mark Z.

 

[[email protected]]

Hi Mark,
I have found another interesting thing, the player gets perfect if I
give it an hour to warm up. This fact told me that there may be some
parts that change their specs according to temperature. First of all I
made a list of all the elco caps and bought some good quality ones
of the same values, and replaced them all, but the problem is still the
same. What if I also have a bad solder connection as you say? Is a
problem like this visible? I just don't want to re-solder all the 6-7
boards in the player. If it's a wrong solder connecion could it be
affected by the temperature?
M