"Rob" wrote in message
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On Oct 2, 6:56 am, "Arfa Daily" wrote:
"Rob" wrote in message

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Kyocera DA-310CX. It plays fine straight through, but when I try to
jump from track to track either forward or backward, it can't lock
onto the next track about 1/4 of the time. The track number is
displayed, but the countdown display stays blank (a series of dashes
across it) and no sound. It either does not play at all or every now
and then it will begin to play after a long delay with the track
number displayed, but the countdown does not start up. When it does
this, it begins to play from a spot inside the track, rather than from
the beginning. Now, if I jump forward, then back again, it does lock
in. It appears to play both CD-R and factory CDs in this way.

Is this most likely a cleaning/lubrication issue? Can I rule out any
problems with the laser or other unfixable problem? When you put a
disc in and play it straight through, it appears to work without any
problems, it goes from track to track smoothly (albeit it with a 4
second delay in between tracks, as designed).

The tray mechanism clearly needs cleaning, as you have to help it open
and closed or it does not move.

I have read the very good tutorial on CD player repair from this site
and will certainly look at the laser for cleanliness, clean and re-
lube.

When playing straight through, apparently ok, how 'tap-sensitive' is it ?
A
clean laser in good order should stand a knock to the cabinet that is
enough
to shake the lens, when there is no disc in - if you see what I mean,
That
is, not violent enough to guarantee a jump, but hard enough to make a
noise.
If the laser is clean, but jumps easily when the cabinet is tapped, it is
likely that the laser is low emission or dirty internally, either of
which
problem means replacing it. Again, if it is a laser problem, a burnt disc
rather than a pressed one, will usually behave worse, due to its lower
reflectivity.

Another possibility, if the player has setup pots, which most these days
don't, is that the E-F balance is a little off. This can cause just about
exactly the symptoms that you are describing. However, it is often the
case
that the E-F balance is poor because of internal dust in the laser, and
without a pot to offset the opamp that the diodes drive into, you're
stuck.
If the laser is one of the Sony KSS series - particularly if it is a
KSS213B
or a KSS240A, then the problem is probably laser related. All the KSS
series
are readily available from multiple sources, and not expensive. They are
not
hard to replace in most players, and if you buy a 'genuine' replacement
rather than a second source 'ringer', they are usually just 'drop in'
without any setting up issues.

Arfa

Thanks Arfa. I went in and posted my results and a picture he

http://www.diyaudio.com/forums/showt...06#post1315606

Optical assy is the KSS-123A and they appear to go for $25. Results
of the tap test are inconclusive. It does jerk it a bit, but maybe
I'm just hitting it too hard? So, what do you think, adjust the E-F
now? In which direction?


I've seen Kyocera's of this type have slightly sagging suspension springs,
so that the disc scrapes slightly as it plays. You might check to make sure
the disc rotates absolutely freely when clamped in PLAY position and that
there is a bit of play in the vertical plane, meaning that the clamper or
disc isn't very close to scraping.

Also, sometimes we see other things - even a bit of hair wrapped around the
spindle motor shaft can cause a problem, and while we're on the subject, the
tray load belt (underneath the mech) is a real troublemaker on these.
Perhaps it's just not clamping fully.


Mark Z.