"aasdf" wrote in message
ups.com...
Hi, I have an old Aiwa CX-NA50 that I bought in 1998. It's a three CD
(3 CD) mini system. From the beginning it would "reject" certain CDs..
it would spin them a couple of times, with a slight clicking, might
bring up the track directories every once in awhile, but most often
would skip to the next cd. After about a year of this it wouldn't play
CDs much any more at all. It's been sitting in the closet since about
1999. Recently I took it out to play MP3s and XM Radio via an FM
transmitter because the little speakers are excellent.

Today I took it apart and fiddled with the little potentiometer
(potter, pot) inside the machine right next to (behind actually, a few
inches toward the rear of the machine) the laser. It was a chore
getting it apart and I had to take off the side and part of the back.
I turned the little potter about 1/8 turn counter-clockwise, and it
started working and now seems to read and play CDs. Whether this will
"burn out" the laser at some point is not a concern to me since it
wasn't working at all before. I tested it to make sure this was
actually the reason by turning the potter back into the original
position, and sure enough it failed to work again. So I'm reasonably
sure this is what's the matter with it, or a "kludge" to get around
what is really the matter.

Previously I had tried to clean the laser, to no avail. For those of
you who have faulty Aiwa systems you should know that there was a
class-action settlement a few years ago that offered to replair the
systems for free, because many of the systems had this problem. It is
a very common problem. Unfortunately the period of time to take
advantage of that has passed, so now you must do it yourself unless you
simply want to pitch the system or pay money to have someone else do
it.

So if your mini CD player is not reading the discs you put in, you may
want to try this fix. Do this at your own risk.


This is actually not good *general* advice. Be sure that the laser will now
totally fail in pretty short order. The laser pot is neither intended to be,
nor ever should be, adjusted with 99% of the lasers used in audio and DVD
equipment. It's setting is carefully determined at the factory as a result
of measuring several parameters. One notable exception is Pioneer, where
there is a proper laid down procedure for adjusting it.

I have repaired many thousands of Aiwas over the years, but far from saying
that laser failure in them is common because of any manufacturing or design
problem, I would venture that the reason I have seen so many, is that I
service them for the trade, and they were a very popular item, sold through
several of the large chains here, so as a value for money item, which I
believe they are, they outsold many other brands and models.

The laser employed in them is one of the KSS series from Sony, and these
lasers are extremely cheap anyway, so if you've gone to the trouble of
stripping the unit far enough to get at the pot, you might as well replace
the laser.

I am pleased for you that adjusting the pot got your unit going to your
satisfaction, but it was possible that the fault lay elsewhere, and
adjusting the laser would only have compounded the problem by resulting in
laser damage. For that reason, if no other, I would STRONGLY advise anyone
reading this thread, to NEVER adjust a laser as part of a diagnosis
procedure, unless it is a valid and manufacturer-recommended procedure. Some
lasers are very expensive ( and very reliable ), and altering the pot on
them, when the real problem may well be some two penny resistor, is likely
to result in a written off unit.

Arfa