Done(-ish) with the Beomaster 5500, it's in service and sounding better than the Beocenter 7700.
So now on to the battered Beogram CD 5500.
This Beogram CD 5500 came to me pre-broken from an eBay seller that had sold it and shipped it without the transport locks engaged and it arrived at the buyer broken. It got shipped back for a refund, likely adding to the damage, and then I bought it as scrap and it got shipped again!
By the time it arrived, the disc transport was thoroughly battered. A pity, the transport locks were safely in the storage holes!
Last week, I got the time to go through it. Fortunately, only one rail was loose due to a non-replaceable rear mount AND the broken piece was still inside.
Some industrial epoxy that works well on plastics got the busted rail mount fixed, lots of Windex to clean out the dirty chassis and drive mechanics, a better belt for the disc tray, put it all together, get the mechanical adjustments roughed in and,..... doesnt read the disc,
Also, sometimes the motor spins backwards! This sound like power related, so a check at the platter motor connector revealed the -9.5 supply was very erratic. Unplug the motor and the supply seems fine. Maybe the motor draws too much current? Out with the mechanism, hook up two 9v batteries, give it a control signal and the motor runs just great. Put it all back together and track the -9.5v supply and it's sagging right back to the diodes. Let's see, even the un-rectified AC sags at the diodes! Check at the power transformer and it's fine. Ah-Hah! cracked solder joint at the main power connector on the main circuit board! Touch up the pins and...... Still won't read the disc, though the -9.5 rail is now nice and steady like the other voltages.
The Internet says C2103 is a good likely cause, so check it and the ESR is way high and the capacity is at 22uf instead of the rated 33uf. Installed the suggested 47uf and... Still no read, except it did just once.
Out with the servo PCB for another look for bad solder joints and, say, what is that sticky substance all over the bottom? Perhaps it's bridging the traces and SMDs? Some alcohol and a toothbrush, try again and now it works! sort of. Move the player just slightly and it conks out. Still, now that it's running, I set the laser current and the focus offset to no effect. They were pretty close anyway.
Finally, another Ah-Hah! It seems that "roughing in" the mechanical adjustments just isn't good enough! Set the disc height and now it runs nicely.
Another Learning Experience!
