wrote in message
oups.com...
I had this unit in the shop about 6 months ago with a bad motor. I
replaced the motor, being very careful to measure the height of the
platter before disassemling the old one . The new one went in without a
hitch and the unit worked fine. It just came back with the complaint
that it would not play. I determined that CD's will play fine but when
attempting to play a DVD I get a No Disc message.
I cleaned the laser and there was no difference. I then swapped the
laser asssembly with one from a known good machine and it works. So I
have determined that the problem does not seem to be the motor. It
appears that it is either in the laser itself or perhaps could the
platter height of my replacement job have been marginal from the last
repair, and perhaps the laser has aged somewhat now causing the CD's
to read OK but not the DVD's.? I'm just guessing here. If a machine
will read CD's should it just follow that it should also read DVD's? I
don't see a power adjustment on the laser assembly and really wouldn't
want to mess with it unless I was sure anyway. Does anyone have any
opinions on this and also a quick easy way to rule out platter height
vs laser aging as the source of the problem? Thanks for any assistance.
Lenny Stein, Barlen Electronics



It's a bad laser, as was recently discussed in detail, DVD players generally
use two separate lasers in a single pickup, one IR for CD's and one visible
red for DVDs. What you're seeing is one of the most common failure modes of
DVD players.