CD63 won't read

I just replaced the laser in my CD63 because it was sometimes skipping. It cured the problem.
But now (a couple of months after the change) it won't read some disks. But will play others fine. It will read a CD-R, scratched old one. But not a new one. Examlpes these not a general pattern.
Does anyone have any ideas as to where I could start tracking down the fault?

 

I've found this with some new, silver CD-Rs in a DPA Enlightenment drive with new laser (same laser model as CD63) and my car's player. But these same 'problem' discs play fine in an old Naim CD2! ( CDM9 - based).

I'm wondering if it is to do with finer track spacing as the CD-capacity is generally increased over nominal thes edays - it's quite easy to get 800MB onto a 700MB disc ...

 

first try cleaning the laser, if that doesn't work then I would suggest the laser is out of focus.

I had the same with my cd50 se cdm 4/19 mech.

 

hmm, what do i do with an out of focus laser?

 

Sounds like the clock may be going

 

OK I've just tried again (few hours break) the problem cds again. They work, although one of them after a few times of turning on and off. Sounds fine when they play. Still sound like the clock? If so what's this like to replace, and how much for a stock one?

 

there is normally a small pot to adjust but make sure it is the right one.

I don't know which one it is on that board.

I think if I were you I would first try cleaning the laser.
then try taking it apart, mark the position of the pots with a marker, the ones near the cd mech, then fiddle with them with a cd playing till it works only move them a very! small amount as it wont be too far out.

well that is what I did I got it checked out with an oscilloscope (the proper way of doing it) by a friend and it seemed I got it right and needed no further adjustment, but I think that was 99.9 % luck

I think there are normally two pots at least one is voltage one is focus ?

hey if you mess it up just buy a new one off ebay (normally the cheapest option)

if the clock is gone it would be worth trying a trichord clock 2 or 4 and getting them to fit it. unless you are familiar with surface mount stuff as it easy to wreck the pcb when you remove the components round the clock chip / quartz bit.


here : http://www.kuro5hin.org/story/2004/3/24/45212/6874

 

if you need the cd63 service manual and schems ....just ask

 

already pulled them off DIYaudio thanks. Might try the adjustment then. I could actually bring it into uni and use an oscillascope in our dynamics lab. What am I measuring where?

 

Probably the laser needs aligning. My dvd player wouldnt play certain discs untill it was set up right. Jim.

 

There are no tracking/offset/focus pots to adjust in the CD63, it uses 'digital' servos controlled by the SAA---- decoder IC.

There is a tiny pot on the back of the laser, which adjusts laaser current - leave it alone! There is also a tiny screw which adjust the grating - haven't tried that, so can't advise... but it's mentioned very near the end of the current monster Maraz Cd63 mods thread over on DIYAudio.

 

I'll second felix ......

could be the problem lies elsewhere

have you run the unit in service mode ?

this should give you an error code ....helping track down the issues.....

press stop and play when you switch the power on ....let me know what the code is !

 

well this is mystifying. The error is not constant. Just tried all the problem cds again, and they all play. So I can't even run the service mode to find the error?