Hans said:
Thanks for the reply! I opened it up, and upon pressing down the thing
that would signify the player being closed (door sense switch as you
said), it looked like it wanted to read, the display went from 00, no, for
no CD. Anyway, the laser head does not move, and it seems rather dim, I
imagine it must be a worn out laser like you said. Thought I'd post here,
mostly out of curiousity
.
If the laser does not appear to try to move when you fool the player into
thinking that the door is closed by pressing on the switch, then this may be
your problem rather than a defective laser.
You will not be able to tell just by looking, if the laser is genuinely '
dim ', as its wavelength is primarily in the infra red section of the
spectrum, where your eye is not sensitive. Any red that you see is only down
to spectrum leakage, but can generally be taken as a good indication that
the laser is burning. Do not look directly into the laser, even though this
is considered to be
a " safe power " device. Only look from an oblique angle.
If the laser is burning, this will normally indicate that the laser is '
home ' and that the sense switch is correctly flagging this to the system
control micro. As well as the laser burning, at this time the lens should
also be moving up and down a significant amount as the optical block
attempts to obtain focus. With most players, if no sensible feedback is
received during the first one or two tries, the optical block will be moved
a short distance, in case it is looking at a dirty or damaged disc at that
point.
I would suggest that you apply gentle pressure to a solid looking piece of
the optical block, using the tip of a small screwdriver, or similar, and try
to push the optical block down its track, away from the centre of the disc.
Even though the block is usually driven by a worm gear arrangement on
portables, gentle force will usually cause the spring loaded pawl to slip,
allowing the the block to be pushed up its runners. When you have moved it a
couple of cms, push the door closed switch again, and watch what happens.
The optical block should first run quickly back to the centre, then the
laser should start to burn, and the focus search sequence should start. When
no disc is found, the block should shuffle about a bit, and try again,
before giving up with the " NO DISC " message. If this happens ok, it's
worth then retrying it properly, and you might just find that it now works.
If the optical block had become tight and got stuck, the act of moving it
manually and then allowing it to return under its own steam, will often free
it off enough to start working.
If it does, then the unit should be dismantled, and the laser sled drive
carefully cleaned of all the old grease using IPA or similar, then relubed
using floil if you can get it, or high quality very light synthetic machine
oil, applied sparingly, if not.
Arfa
