CDM 2/29 Problem – HELP!

[Bassivus]

A few days ago I was doing some work with my Grundig CD 9000. I found that the four-lead cord from the servo board is quite stiff and that it pulls or pushes the wobbly CDM, so I decided to change it with more soft one. I changed the solid wires with the litzy wires that I took from microphone cable. I got stuck with the little connectors for hours just to find that I have fitted two ends in wrong order. I had no more patience to disassemble all again so I cut the wires and soldered them together in proper order. I checked with DMM all fine.

I fired up the player and it started spinning the disc but doesn’t recognize it. The laser makes two tries upon startup, up and down, but no lock… Since than I have been searching and reading but found no solution that works for me… I have found service manuals only for similar players but there is no servo or CDM schematic… My player uses the same main board as Philips 640, 650, 660… but CDM 2/29.

I can provide photos of the board/player for someone that has the patience and goodwill to help!

Could it be that new no solid wire makes the problem?

Here is the photo of the servo board (without THE cable)

[aparatusonitus]

Hi Bassivus,

Mail me, I have a service manual for CDM2, the board image in your attach is the same as in manual.

[stoolpigeon]

These plugs are designed for a specific size solid core wire because the action of assembling them cuts through the insulation and makes the contact.

If you have disassembled them and used different wire this could be your problem.

Removing these plugs can also crack the dreadfully cheap circuit board used by Philips because you need to bend down the locking tab for removal. I did this and the crack in the board just happened to be where a track was. Took me a long time to find it.

[Bassivus]

Hmm,

I think you are talking about the connector type like we see today in computers. These are in fact 20 years old type with separate chambers for each contact and connector feet you can take out.
At least the disk spins and the laser tries to do something when its connected, only it does not read the disk...
Here is the pic of the wire and connector foot taken out:

[Bassivus]

I have got the manual now, thanks to aparatusonitus so I hope i will be able to do something... I am more and more convinced that I must have done some harm during disassembling of the CDM and servo board, perhaps disturbing some old bad joint.

In previous posts I have forgot to mention that it is the motor power cord that I have changed, +2, -2, ┴, Vc .

[Bassivus]

Only thing I am able to find suspicious is that I don't measure nothing across the 2136, and the manual says I should measure +-400mV adjusting the pot 3146! If I could read Dutch...

[aparatusonitus]

Bassivus, please do check your mail, I've sent you another one in english, yesterday I think.

[stoolpigeon]

aparatusonitus, could you send me the service manual please.

Bassivus, this is the connector I am thinking of. The wire goes in unstripped and the v shaped part of the pin is forced over the wire, cutting through the insulation and making contact.

You can of course check the continuity from socket to socket (cable plugged in obviously) to see if your connections are ok.

[tubee]

I have dealt too with cdm2 a few times, had same errors.

There is also a big (9 wire?) connector for HF signal to SAA7210 , this one can have faults too. (servo pcb to decoder pcb) Best is to repair that cable as the 4 pin, a check with DMM allways proofs nothing, when reassembled the fault re occurs, i had that at least. After 18 years of duty some connectors may oxidise. Or the solid wires can be broken on the ends.

The grey philips connectors can be dismantled, the copper pins have a fork wherein the solid core wire makes contact after pressing the connector parts together.
I have repaired some: First align the wires on both ends with tape. After dismatling of connectors (lift clips) shorten wire 3 mm each end. Press all the tiny forks a little bit smaller with a small flat gripped tool, and reassemble connector, by pressing it carefully in a bench vice. Before that check if all wires are in the correct position in the connector, not too far in or out of it. In special the big connector has to be pressed some to be reassembled. The vice helps to press the parts straight aligned (parallel)

Btw the whole wire assembly with connectors is allways mirror-symmetric. (pin 1 becomes pin 4 in a 4 pin connector) and the connector has a wedge for fitting in the female pcb part, it is pounting outwards

Good luck.

[aparatusonitus]

Originally posted by stoolpigeon
aparatusonitus, could you send me the service manual please.

Of course, it's about 15Mb so be shure your email account can take it..mail me please.