Rotel RCD 965BX stops playing after several tracks

[jnewbold]

Hi,

I have a Rotel 965BX player that I modified almost year ago, mainly new and additional PSU, regulators, op-amps and Tent clock. It has been working well since then and the mods were a big improvement.

However, the player stops playing after about forty minutes, on every CD. The track number it stops on is different for each CD and it stops at any point in the track, so it seems to be a time based thing, although I haven't timed it exactly.

There is no obvious obstruction to the movement of the laser swing arm.

When I use the remote or the front panel buttons to try to get the player to read the next track, the laser just searches, unsuccessfully, and stops searching after a few moments. If, for example, the player stops on track 8, I can go back to track 7, or to the beginning of track 8 and the track is read – until the same point is reached and off it goes.

Any ideas?

[Sonusthree]

I would clean and re-lubricate the laser sled. Often the old grease will harden and accumulate in a particular spot giving the symptoms you describe.

[stephensank]

There is no laser sled on a 965. It uses a CDM-4 radial tracker.
The symptom sounds like either cold solder joints, usually in the supply, or failing electrolytic capacitors(usually Philips), which could be anywhere on the main board. Particularly look for any caps that are axial & blue.

[jnewbold]

Originally Posted by stephensank

There is no laser sled on a 965. It uses a CDM-4 radial tracker.
The symptom sounds like either cold solder joints, usually in the supply, or failing electrolytic capacitors(usually Philips), which could be anywhere on the main board. Particularly look for any caps that are axial & blue.

Yes, it has a CDM4 and the radial arm moves very freely across its full travel. Thanks for your suggestion of cold solder joints. I will check. However, all the electrolytics on the PCB have been changed to either, Elna Silmic or Panasonic FC or Nichicon ZA, depending on their location.

While I have extensively modified (upgraded?) most of the power supply, I have not touched the power supply to the CDM4 and associated digital bits.

I am mystified as to why the CDM 4 reads up to a certain point on track and then stops reading at that point. I can then send it back to the beginning of the track and it reads the track, but stops at the same point. I suppose In really should time it accurately on a couple of CD's

Cheers,

Joe

[jnewbold]

Originally Posted by Sonusthree

I would clean and re-lubricate the laser sled. Often the old grease will harden and accumulate in a particular spot giving the symptoms you describe.

[QUOTEOriginally Posted by ]stephensank: There is no laser sled on a 965. It uses a CDM-4 radial tracker.[/QUOTE]

I have found the problem and it was connected with the swing arm of the CDM4, but not too far from Sonusthree's suggestion. I thought the swing arm was travelling properly, but on rechecking it I discovered slight check or hesitation in its ravel. I thought maybe the ribbon cable was catching on part of the mechanism.

So I dismantled it and was surprised to find an insect pupae attached to the inside wall of the well in which the arm swings. The pupae was about 12mm and was catching the ribbon cable and retarding it enough to stop the arm swinging freely.

That's why the music stopped after about 40 minutes on every disc.

Now, each track on every disc is played. No problems.

I have included a photo of the pupae. Although the focus is poor you can make out the brown coloured object (inside the red oval) in the curve of the swing arm well and the ribbon touching it.

Cheers,

Joe