Mark D. Zacharias wrote in message
.net...
wrote:
Couldn't that only happen if the clock frequency slowed due to a
faulty crystal or loose loading cap or related fault.

I suppose it could be that or even a mechanical failure (servo motor
problem,
not enough lubrication, spindle off center, spindle bent), power
supply rails at the motor or controller not to spec (too low or too
high). I'm just wondering what the most likely causes are for the
scenario that I've presented.

Mike


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

A regular CD player can only slow down a small bit and still get
intelligible audio. As it slows down a bit, the sound may get static-y and
at some point probably cut out. Decoder IC's are locked to the incoming
signal via a crystal oscillator. If the frame drop-out exceeds a certain
amount, they just mute or stop playing.
Don't adjust the potentiometer on the pickup - this is a laser power
adjustment and at best it would accomplish nothing for you, at worst it
would destroy the laser diode.
Wouldn't hurt to clean the lens and lube the spindle motor top bearing -
but
don't expect any miracles.

Mark Z.



I would have thought a bit of braking would have no effect until its run out
of repeat redundant code and then drop out rather than drop pitch.
Next time I have one open I will try loading the timing crystal and see if
that drops the pitch even if only for 1/2 second or so.
I've come across a cracked crystal from being dropped causing intermittent
problems, not in a CD though.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/