On 31 May 2007 19:30:37 -0400, Sam Goldwasser
wrote:


It does realize it's an LD in there and not a CD, right?

With any RF, it's focusing. I assume you mean 10 rps. I doubt there is
any way it can conclude the LD is bad at 10 rps. I assume you've tried
more than one LD.


It does correctly say LD in the display. I actually do mean 10 RPM!
It's a stretch to call it RF at that speed, but there's a definite
signal at the test point. I compared it to a different LD player and
it spins up the disc as soon as it detects it.

It's definitely a problem with the LD spindle servo which is separate
from the CD servo. There's virtually no voltage on the LD spindle
error line (which is labeled on the board). I tried applying an
external voltage to it through a 10 k resistor and the spindle motor
immediately came up to speed (of course, not in sync). I traced the
error signal back through an amplifier circuit and everything seems
fine there. It then goes back to a large custom IC.

By this time, the player was working better than before. It was
actually spinning the disc at almost the right speed and produced
intermittent video. After allowing it to cool down it was exactly as
it was before. Leaving it turned on in stop mode for about 30 minutes
is enough to get it to start partially working again.

Clearly there's a thermal problem. Hopefully just an electrolytic
somewhere. A couple of times it has suddenly turned itself off
without warning (as if I had pulled the plug). I'm going to pull the
power supply and also check the various regulator circuits scattered
around the other boards. Fortunately, unlike most Pioneer LD players,
most of the boards are accessible while the player is assembled.
Andy Cuffe