It took me years to find a decent Laserdisc player in Austria, and a few years ago I managed to get a Sony MDP-650 at a foreclosure auction. I was the only bidder. There is neither supply nor demand for LD players in this country, which isn't surprising as the system was never really popular here, so barely anyone even knows that these things exist.
Anyway, my player worked perfectly fine for a few years (I just had to replace the belt that connects to the gear lifting the LD at first), but recently it stopped working.
What happened was:
- The disc gets raised
- The disc gets lowered (this is how it always goes, so nothing unusual here yet)
- I press play
- The disc gets raised again
- The laser module moves back and forth around 4 times, with about 1 second between each try
- The disc gets lowered again, the player just displays "disc"
It was the same for CDs and LDs, which made it unlikely for the Laser to be the issue as it was unlikely for both Lasers to break at the same time. I suspected the skew motor, which keeps the Laser in focus, but upon closer examination the skew motor was fine. I did however manage to get the player to play discs by turning the skew motor in a way that the Laser is very low. The player could then read discs for a few seconds.
Thanks to a suggestion by the user rein-o in a thread I posted at the lddb.com forums I figured out that the discs were at the wrong height, so I found out where to adjust that and got it to a height where the player seems to be working after a few tries. It seems that the platter slipped down slowly over the years and just needed some readjustment.
I hope this helps if you're experiencing the same problem. I also have a PDF of the Sony MDP-650 service manual, so if you're in need of that, just drop me an e-mail!