I dunno if anybody remembers this thread:

http://forum.beoworld.org/forums/thread/106583.aspx

I never did get the old CD mech to work... However, I managed to get a complete BC8000 CD assembly from some service center clearup. I checked the preliminary laser current adjustment (1 kohms over R3105 + R3106), plugged the mech in, and it spun the CD and started to play right away!

However, since the actual BC8000 service manual is not on site and I can note a number of discrepancies between the BC9500 manual and this machine, I plugged it off instead of tweaking anything further. can anyone confirm if this is the correct way of adjusting this:

1. Laser current: DC voltmeter across R3102, adjust R3106 to 50 mV +/- 5 mV;
2. Focus offset: test mode check no.2, adjust R3146 until display shows 02; further adjust until there is 400 mV +/- 40 mV accross R2136

?

(and oh yes, the new CD mech is similar with regards the spindle motor: just two leads directly soldered on the PCB)

AFAIK these are the correct adjustments. I have never seen any others quoted for CDM4 devices. Several versions of the CDM4 were fitted to the various Beocenters but are essentially very much the same and you can usually mix and match without problems.

If it works dont fix it!

Well, I did these adjustments (but of course I don't have the test CD, so I used a clean regular one) after all the cap upgrades recommended in the workshop.

It does read CD-R's now also, although it refuses a very scratchy one I've kept as a rudimentary player quality test disc. This must be the first time I've had the patience for a six month project! The girlfriend is already excited about the new Beocenter she'll get next weekend I'll keep the old CD module for mechanical spares...