CDM9 /65 problem, help needed!

[Malefoda]

Hi,

in order to keep or not a CD951 with a CDM9/65 I want to try to fix a problem:

take appart the fact I've changed some parts in the player (caps, opamps... ) as it was faulty out of the used box, I now can repeat conditions for troubelling the CDM, taking disc in and out and then try to play track 1, it does maybe 1 time on 3:

• More or less slow TOC reading, once on 50 completely refuse, power off/on then starts again fine,
• when TOC ok then press play and access track 1: slight noise, a delay of around 4/5 sec, then a "gzzztttt" noise wich seems to be the lens arm motion and starts to play, or no noise and "Error".
• when TOC ok then access later tracks as 3 then it almsot start immediately,
• when come from start to last track the laser arm is very slow to access it, but when there it runs fine.

All this with any disc, same behavior with real CD or CDR-W.

So far and after some reading,
Service mode shows no error,
I've checked the free motion of arm, it's seems OK,
I've run the motor alone on 7.5V and slightly lubricated the bearing from a small hole under,
no success.

Beside this one my CDM12 is faster than light ( and so noisy! )

Thanks for helping,
Matthieu

[Malefoda]

Have sneaked around the Net, tried the PFM's tips like pull the disc platter a bit up & down to see, no change.
It's defo a problem accessing track 1 from stop position. But not with some pressed CDs, not at all with CDR-Ws, but with some CDRs wich sometimes work fine, a test with a good (but 10 year old now!) Kodak Gold CDR burnt with maybe something like a x1 or x2 burner long time ago... even don't want to start from track 2!
They all run fine if I start accessing track 3 or further then ask 1.
Maybe it's just a media & burner problem? Have some of you guys seen that?
They do fine in other gears.

Matthieu

[Malefoda]

Don't want to read? Ok, here we go:
YouTube - MOV00218.mp4

One CDR on a CD/CDR-W/CDR/CDR test has problem starting.

[martin clark]

It might be something really simple. The TOC is right at the centre of the disc - have you checked there's nothing stopping the arm/laser head from travelling far enough toward the disc hub?

[Malefoda]

Sir yes sir!
As it always reads the TOC and I'm no more sure it ever failed, that should not be that anyway. And it moves freely.
But, in matter of bunring CDs flaws, the ones who have difficulties to be read at the very first tracks, 1 and 2 at least, where burned in Track At Once mode, meaning the laser burns well after a while therefor have a delay of 2 secs between tracks, and all other in Disc At Once mode, so only the first track has this "fully warmed up" laser issue. And such disc have problem... only at track one!... any link? And CDR-W where burnt several times, maybe first bits are very neat now?

Maybe I should try turning the small potentiometer on the ribbon? A potentiometer is meant to be turned anyway...

"Really simple"... ok Martin, let me introduce you Mr Murphy, and my friend Murphy has a law...

[event horizon]

I think you may well find that the laser is on the way out

What you just showed with that youtube link reminded me of a problem i used to have with a Theta Data Basic CD transport. It would play most cds fine & always read the TOC, however it messed about with certain cds on the first track as yours appears to be doing. This one would even do the same thing on normal cds with a couple of discs. Once the CDM9 Pro laser assembly was swapped for a new one it never missed a beat

Have you tried cleaning the lens? If not get a cotton bud & some isopropanol & very gently give it a clean to remove any dirt/dust etc. Just lightly moisten one end of the cotton bud with the isopropanol & gently wipe all over the lens, then use the dry end to clean & dry it..

If you do this please turn the power off beforehand (though i'm sure you aren't daft!).

Good luck.

[Malefoda]

Yep and that makes sens with the weakness of burnt at the begining of tracks as they are less clean... and I've confirmed that with other disc in DAO with first track and TAO with some tracks... and cleaned lens of course
Maybe it's time to mess with the pot on the head...

[martin clark]

A potentiometer is meant to be turned anyway...
A very small pot is meant to be set in the factory and left alone by people who don't have teh calibration details...

"Really simple"... ok Martin, let me introduce you Mr Murphy, and my friend Murphy has a law...
Very true.

- And I haven't encountered the exact problem you describe re: cdrs. Sorry!

[Malefoda]

That pot storry is just a stupid statement in order to allow myslef doing what I should not
After... touched the pot in one way or another, messed more or less the player (and had no better anything), I've check more about that problem and found more stories of too old lasers.

This is the end!

Thanks Martin and Event Horizon, a last word for this old beam?
As for me: "rust in peace".

http://www.hifidiy.net/channel3/2007...070623_943.htm

[martin clark]

Well then: you can either rob the corpse, or sell it on ebay to someone who wants to...