Andy Cuffe writes:

On 22 May 2007 08:56:26 -0400, Sam Goldwasser
wrote:

Andy Cuffe writes:

This high end laser disk player from 1990 plays CDs fine, but when a
LD is inserted, it only spins for a few revolutions before it ejects
it. My first instinct would be to say the optical pickup is bad, but
other LD players I've seen with problems try a lot harder to play
before giving up. I don't think it's the spindle motor because when
it's playing a CD it has plenty of torque (I actually can't slow down
the disc by holding the spindle). The pickup moves freely and the
tilt motor is working. Since I don't have a service manual, I'd like
to hear any ideas before I really dive into it.

So the spindle motor on this one is used for both LDs and CDs?

With only a few revolutions and I assume never getting up to speed, it
can't even know if the LD is valid so sounds like it may be shutting
down due to another problem.

There is also the newsgruop alt.video.laserdisc though they don't do
much in the way of repair there.


Yes, it uses the same motor for both which is obviously massive
overkill for CD playback. Since it has lots of torque when playing a
CD, I would think it could spin a LD faster than it does.

It never gets faster than about 10 RPM when loading a LD. I can see
some RF at the test point (although way below its normal frequency due
to the low speed), so it must be more or less focusing.

It seems strange that it gives up so fast. Other LD players will
grind away for a couple of minutes when they have trouble playing a
disc. It's also odd that it ejects the disc when it fails. I'm
hoping someone can tell me what this model normally does when it can't
play a LD.

I've already checked for obvious problems such as power supply
voltages and gross mechanical problems. I'll double check for sensor
problems that might be causing it to reject the disc.
Andy Cuffe

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.

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