Need help repair an ADCOM cd-player

[PowerAmpFreak]

I need some advice with a repair of this CD player, GCD-575. Please see the attached pictures.
The problem is reading is erratic. I changed the laser, KSS-210 already with no special improvement.
The problem is like this:

Insert a CD, spins up correctly and read the TOC quite fast, so far so good.
Normally starting at track 1 is generally no problem either.
But to skip tracks is troublesome. For example, going from track 1 to 2, will make the laser-sleigh go all the way to the outer edge of the CD and after a while, go back to center and occasionally succeed to read decided track.
I can't understand why the sleigh walk all the way to the edge.

Appreciate any advice!

[stj]

Re: Need help repair an ADCOM cd-player

sounds like the early playstations!

look closely at the sled and runners for flatspots or dried grease.
also look at all the gears for damage.
it should move smoothly with no play or binding.

2 big problems with old players are the sled running on plastic rails rubbing the plastic down, and grease going hard.
specially with sony build gear!

temporary test - once you replace the missing washer & screw at the rear-right mount is to run the unit upside-down.
that will detect worn runners

[PowerAmpFreak]

Re: Need help repair an ADCOM cd-player

Thanks,

On the laser unit I saw a few really worn out plastic teeth and this black plastic had went into the white gears, resulting in bad smoothness of the sleigh.
I then replaced the laser (including the plastic teeth since it's included in the laser assembly) and I also cleaned the white gears and now it seems to walk very smooth over its entire range.

I will try that upside down test, by the way, how will it detect worn out runners?

[PowerAmpFreak]

Re: Need help repair an ADCOM cd-player

I found another complete mechanics incl laser assembly and tried it with no difference to behaviour of the sled.
This must be caused by some electronic failure.
Then I believe this will not be worth looking for...

[stj]

Re: Need help repair an ADCOM cd-player

it could be as simple as a cap, i bet there isnt much to the sled motor drive.

[vinceroger69]

Re: Need help repair an ADCOM cd-player

maybe worth a read
http://www.diyaudio.com/forums/digit...gcd-575-a.html

[R_J]

Re: Need help repair an ADCOM cd-player

A lot of the laser pickups I'v changed over the years had problems with the clv motor, the one that spins the disc, if its in poor condition it won't respond to the drive signal properly, Sony & Panasonic had a lot of problems with the motors, I even recieved new Panasonc assembles that were bad right out of the box.

[charis]

Re: Need help repair an ADCOM cd-player

When reading the toc and after the laser goes to the end and back is because try to correct the tracking and focus to servo.
When you change laser you have to reset servo.
Some will do this again and again when you put another disc inside to calibrate.Then the cd plays natural.Dont adjust the potensiometer on the head especially on KSS if you dont have proper measure equipment.
Sometimes the problem is on plate and especially the springs make an small angle so when you pass the midway to cd start to jump.
Alot of KSS are not genuine and sometimes the genuine ones is destroyed from static or bad storage.

[Electone]

Re: Need help repair an ADCOM cd-player

Try a drop or two of oil on the shafts of each of the motors in the unit. Allow the oil to wick itself down into the motors. I had a skipping Sony that was cured by this procedure.