Philips CD 202 - Fixed!

phimor

Member
2004-02-06 7:35 am
Adelaide
Hi,

I'm a relative newbi to this board, though I have looked in over the years. I got some success with repairing a CDP today (after weeks of trial and error) so I thought I would share what I learned. I know the search function was a great resource for me, I hope this helps some-one.

Well, the CD202 would play from cold, then after a short time it would speed up (wierd - hey) not so much a rise in pich as just a faster beat. Then the sound would distort - become sort of metallic. I imagined something like a Dalek playing music, if Daleks played music. This was followed shortly by just noise and shut down. Repeated starts only shortened the time before failure, until it would not even read the TOC.

After mining the archives I replaced all electro caps, to no obvious change. I then found a reference to the Philips manuals, which I ordered. Now this really helped (though my Dutch is as good as my Mandarin - at least the pictures were good).

This variant of the CD202 is the early one, with a hybrid Sony board doing the error correction, before Philips came up with the SAA7020. The disk speed control is done (in part) through a bunch of 74LS chips rather than a dedicated chip (like the SAA7020). For some-one who knows nothing about electronics, this was a great introduction to not so integrated control systems.

Anyway after many frustrating trial an errors (my soldering skills are now second to none!) it was a HEF4046, described as a PLL, which I understand to be a phase locked loop.

Some of you wiser heads are probably smilling at this, as a loss of synch with the data stream was probably some timing/locking problem.

I managed all this with not electronic background, but some serious study of the schema and reading a lot of posts on this board. So thank you for being here.

Why bother.

Well I like the sound this player makes, unmoded. I have another in the same generation but greatly moded by a professional outfit - A MCD by Meridian. I find little difference between them. If anything the Philips has better timing, though the Meridian is more 'accurate'. Both are warmer than my 206 DS, though not as clinical.

Ok back to it, I have to close the case back up, and start on the next project - B&O CDX :D

Cheers

Philippe