BeoGramCD 6500 with focus issue ??

Hi all,

i have been working on that CD player fir a while:

what started out as a possible Datalink issue seems to be a different issue.

the player plays a couple of CDs perfectly fine and suddenly won’t read another disc - starts to spin, 

and stops without reading the TOC.

i have been through the service mode procedure x times, set the focus offset as per manual, checked the

laser current - all fine…..well, for a couple of discs that is.

it looks like the focus offset is breaking down after having played some CDs in a row.

All elco caps on the servo board have been replaced - the famous blue axial philips cap has been replaced with its Vishay replacement.

the laser supply voltage is present.

suspicious solder joints have been reflown - the two big golden Roederstein caps from the power supply on board 5 have also been replaced.

i wonder if one of the ICs on the servo board have a problem ??

the laser is not dead but my main suspect is the focus offset setting - something seem to break down ?!

at the end as usual: any inputs, suggestions or solutions are desperately needed here.

thank you 

ALF

I’ve had a strange focus issue, too. Take a very close look at the laser lens. The neodymium magnets may have developed some needles which fills the magnetic gap.

Thank you for your input,

however that doesn’t seem to be my issue - after closest examination of the lens I could not detect any of those deposits ☹️

i did a run and checked all voltages again - present 👍 

pushing in the unloaded tray gets the laser in and I can see up/down movement, indicating it tries to focus…..but

exactly that up/down movement is not always present……….which could tell me there is a focus issue or do I interpret that wrongly ?

The two ICs involved with focus are IC6101 and IC6104 - the latter powering the focus motor, unless I read that wrong ?!

I still believe the problem has to be found on the servo board and not on the laser.

Remember, on a good stretch I can play 4 or 5 CDs without an issue.

still positive we can fix that 👍 with a little help from some friends

ALF

I would order a caps kit from Martin, it has the proper cap for C2103. Any other won’t work.