CD Player won't recognize disk
Bearded One
History: No recent falls, powerfailures, breaker trips.
The CD player powers up, and all LEDs function normally. When any disk is
inserted, the unit doesn't recognize that it's in there. The LED readout
asks for a disk by displaying "disc."
Any ideas?
Thanks
CLSNOWYOWL
use denatured alcohol on a damp swab and then apply. After afew seconds, then
dry off with a dry swab. Cleaning usually will help. If the problem persists
after a thorough cleaning ofthe lens, then you will need to check the sled
motor & lube (which actually moves the laser back and forth), spindal motor,
(which turns to cause the disk to spin).
Also checking laser power and laser alignment (focus offset, focus gain, and
tracking) with proper test equipment is also a good idea.
Bearded One
clsno...@aol.comjoe345 (CLSNOWYOWL) wrote:
>If the problem persists
> after a thorough cleaning of the lens, then you will need to check the sled
> motor & lube (which actually moves the laser back and forth), spindal motor,
> (which turns to cause the disk to spin).
>
> Also checking laser power and laser alignment (focus offset, focus
gain, and
> tracking) with proper test equipment is also a good idea.
The laser has no glow. Is it usually visible? I'm not looking at it
directly as per warning.
Spindle motor not turning, but noticed it barely budges forward sometimes
when powering off.
The laser repositions when powering up (good) and the whole carriage
ejects and closes with no problem.
Thanks for the suggestions. Any other ideas?
CLSNOWYOWL
what you found, but you need to verify this. Spindal motors put out about 6-9
volts DC to spin the disk.
Disconnect the power and unplug the spindal motor from the circuit board.
Connect up some clip leads from a 9 volt battery and run from + to + and - to
-. If the motor doesn't turn or labors when turning, it needs to be replaced.
also, placing a volt meter and measuring the voltage of the motor as it turns
is another way to confirm whether the motor is good or bad. Below 5 volts, the
motor is no good.
Sounds like the Laser is actually ok. No, you are not sipposed to see a glow
without an infrared card in front of the laser.
Subject: Re: CD Player won't recognize disk
From: beard...@nonvalid.com (Bearded One)
Date: 10/8/00 3:40 PM Pacific Daylight Time
Message-id: <bearded_One-08...@lai-ca4b-21.ix.netcom.com>
Sam Goldwasser
from an oblique angle while it is attempting to focus. The actual laser is
10,000 times more intense than it appears since the eye is not very sensitive
to 780 nm but most people will see something.
--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html
Bearded One
clsno...@aol.comjoe345 (CLSNOWYOWL) wrote:
> Actually, it sounds as though you might have a weak spindal motor, based upon
> what you found, but you need to verify this. Spindal motors put out about 6-9
> volts DC to spin the disk.
>
> Disconnect the power and unplug the spindal motor from the circuit board.
> Connect up some clip leads from a 9 volt battery and run from + to + and - to
> -. If the motor doesn't turn or labors when turning, it needs to be replaced.
> also, placing a volt meter and measuring the voltage of the motor as it turns
> is another way to confirm whether the motor is good or bad. Below 5 volts, the
> motor is no good.
>
> Sounds like the Laser is actually ok. No, you are not sipposed to see a glow
> without an infrared card in front of the laser.
Thanks again for your responses.
VOM showed a negligible voltage across the spindle motor while on board
(soldered in)
Off-board testing (with 9V Power supply) revealed what seems to be a fully
functional spindle motor (spins fast).
(I also noticed that when the spindle motor is off-board, the
repositioning of the laser doesn't take place on powering up.)
Power to the board has been confirmed. A red and orange wire deliver
8.5V, but when the spindle motor is reattached (at the (+) terminal) and
the unit powered up again, the voltage is zilch after 2 negligible
deflections (< .025V) and short duration moves of the VOM.
What could be next?
Bearded One
(Sam Goldwasser) wrote:
> RE: CD Laser. You should actually see a tiny red dot in the lens if viewed
> from an oblique angle while it is attempting to focus. The actual laser is
> 10,000 times more intense than it appears since the eye is not very sensitive
> to 780 nm but most people will see something.
Yes, there was a red light when I viewed it from an oblique angle with
black paper surrounding the laser for contrast, but It didn't seem tiny.
Hope my eye didn't get zapped. Any experience with this? It was only less
than a second til I turned it off again.
Thanks for your response.
Bearded One
> RE: Light from CD laser. No, you didn't get zapped. Since the beam is highly
> divergent from the lens, your eye can't focus it a significant portion of it
> to a small spot on the retina, thus no damage. Maximum output power is less
> than a mW at the lens anyhow - much less than a typical laser pointer - and
> the only way to have any possibility of damage from those is to stare into
> the collimated beam - I don't know of any substantiated cases of permanent
> vision damage from laser pointers and certainly not from momentary exposure.
>
> --- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
> Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
> +Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
> | Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html
Thank you Sam.
Sam Goldwasser
> Yes, there was a red light when I viewed it from an oblique angle with
> black paper surrounding the laser for contrast, but It didn't seem tiny.
> Hope my eye didn't get zapped. Any experience with this? It was only less
> than a second til I turned it off again.
> Thanks for your response.
RE: Light from CD laser. No, you didn't get zapped. Since the beam is highly
garage
the disk, it does this by moving the lens up and down a few times.
Some players focus then spinup the disk, others need to spinup first, so
check the motor is supplied during focus phase in case...
Wanna see a destroyed site?
Http://garage.free.fr
Bearded One
beard...@nonvalid.com (Bearded One) wrote:
> VOM showed a negligible voltage across the spindle motor while on board
> (soldered in)
> Off-board testing (with 9V Power supply) revealed what seems to be a fully
> functional spindle motor (spins fast).
> (I also noticed that when the spindle motor is off-board, the
> repositioning of the laser doesn't take place on powering up.)
> Power to the board has been confirmed. A red and orange wire deliver
> 8.5V, but when the spindle motor is reattached (at the (+) terminal) and
> the unit powered up again, the voltage is zilch after 2 negligible
> deflections (< .025V) and short duration moves of the VOM.
>
> What could be next?
Still don't know where to go from here. Any suggestions would be appreciated.
Sam Goldwasser
With the motor (and spindle) removed, it can't detect a disc so that
is why I assume it doesn't attempt to reset.
--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html
jerr...@hotmail.com
gentle. If this does not work it may be something that is obstucting
the free movement of the laser along its sled rails. This must also be
checked. The spindle motor must be free to spin.
If these basics are okay, then the problem can be a bad ribbin cable,
loose connection, or a cold solder connection in many cases. The last
place of a problem can be a circuit failure that would require proper
troubleshooting and analysis.
Jerry Greenberg
http://www.zoom-one.com
--
In article <bearded_One-07...@lai-ca4d-246.ix.netcom.com>,
Sent via Deja.com http://www.deja.com/
Before you buy.
Bearded One
> beard...@nonvalid.com (Bearded One) wrote:
>
> > VOM showed a negligible voltage across the spindle motor while on board
> > (soldered in)
> > Off-board testing (with 9V Power supply) revealed what seems to be
a fully
> > functional spindle motor (spins fast).
> > (I also noticed that when the spindle motor is off-board, the
> > repositioning of the laser doesn't take place on powering up.)
> > Power to the board has been confirmed. A red and orange wire deliver
> > 8.5V, but when the spindle motor is reattached (at the (+) terminal) and
> > the unit powered up again, the voltage is zilch after 2 negligible
> > deflections (< .025V) and short duration moves of the VOM.
> >
> > What could be next?
In article <SAM.00Oc...@saul.cis.upenn.edu>, s...@saul.cis.upenn.edu
(Sam Goldwasser) wrote:
> Did it focus successfully with the spindle in the proper position?
>
> With the motor (and spindle) removed, it can't detect a disc so that
> is why I assume it doesn't attempt to reset.
Yes, I think it tried to focus when I originally powered it up. The lens
would moves and then nothing would happen. The problem is that the
spindle motor doesn't spin when on board and it appears as if the CD is
not recognised Don't know what you mean about resetting.
Bearded One
> >beard...@nonvalid.com (Bearded One) wrote:
> >
> >> VOM showed a negligible voltage across the spindle motor while on board
> >> (soldered in)
> >> Off-board testing (with 9V Power supply) revealed what seems to be a fully
> >> functional spindle motor (spins fast).
> >> (I also noticed that when the spindle motor is off-board, the
> >> repositioning of the laser doesn't take place on powering up.)
> >> Power to the board has been confirmed. A red and orange wire deliver
> >> 8.5V, but when the spindle motor is reattached (at the (+) terminal) and
> >> the unit powered up again, the voltage is zilch after 2 negligible
> >> deflections (< .025V) and short duration moves of the VOM.
> >>
> >> What could be next?
> >
In article <1mirus88ouh2r8mje...@4ax.com>, Robert
<byr...@email.com> wrote:
> I fixed a Technics changer with this sort of problem. It had a bad
> dual op--amp that drives the spindle motor. It was a surface mount
> device.
>
> Robert
That wouldn't be more than an 8 pin device would it? Got lots of those in
there but a few much larger chips as well.
Mark D. Zacharias
to dust let in by useless cosmetic "cooling" slits. Often cleaning doesn't
help - too much has got inside to the turning mirror or grating lens.
Mark Z.
"Bearded One" <beard...@nonvalid.com> wrote in message
news:bearded_One-04...@user-2initmr.dialup.mindspring.com...
Steven Rice
Seeing a lot of the same thing with the latter bookshelf units (esp. those
with cooling fans for the amp sections and a large number of cooling slits
in the upper section.)
However, I have had good luck removing the black plastic covering around the
focus/track/lens setup and blowing-out the interior with 60+ psi air. This
seems to take care of interior dust. But it doesn't resolve the problem of
'oily' deposits on the optical surfaces, usually caused by smoking, cooking
or (esp. in wintertime) a good roaring fireplace. I personally intend to
try disassembly and cleaning of the various optics for as many units as I
can find, just to see if there is a significant change (when I can ever find
the time of course!) I will post all results of these attempts here.
"Mark D. Zacharias" <mzach...@kscable.com> wrote in message
news:sRcN5.14730$Se1....@typhoon.kc.rr.com...
Mark D. Zacharias
observe the RF waveform before and after, and the difference is miniscule if
any. But hope springs eternal, and I'll try it a few more times, who knows?
Mark Z.
"Steven Rice" <pu...@efortress.com> wrote in message
news:ComN5.15434$BW2.7...@news-east.usenetserver.com...
SATS
PSX and repair the CD electronics....i might be able to help>>>>