DCC900 does not record

[thechosen2k]

I’m new to DCC but have a lot of experience with other types of A/V equipment.

I recently got my hands on a DCC900 that, as far as I know, has never been serviced. After some experimenting, I noticed that the analog playback volume on the right channel was lower than the left — and both were too low overall.

After doing some reading here, I realized the SMD caps needed replacing. I did that, and now analog playback is working fine. I cleaned both boards with IPA and didn’t see any damaged traces.

The deck came with a bunch of prerecorded DCCs and some self-recorded ones. Playback of the prerecorded tapes is flawless, with zero errors. Some of the self-recorded ones play fine too, but others have error issues. At first, I thought it was the felt pads, but the issue shows up on two tapes with second-generation felts. Kind of odd.

Recording doesn’t work at all. It writes the track numbers, but no audio gets recorded. Even on a tape that plays back perfectly, the recorded section shows a lot of errors.

Could this be due to worn pinch rollers? Even though the prerecorded tapes play fine?

I haven’t checked the vias — how should I go about that? Could they be part of the problem?

Any ideas what else might be causing this? I’d really love to get this deck back in working condition.

Thanks for your help!

Greetings from good old Germany!

[drdcc]

Hi And Welcome,
The problem is common unfortunately. It will not be caused by the pinch rollers, but either by a defect in the RW board or a broken head. The RW is usually the first problem to look at. Check all via’s. We have new RW boards available in our store if needed.

[Sergey]

If the playback of DCC tapes works well (and you can really hear the music) and service mode shows 00 00000000 most of the time (it can be some errors like 1 across all the channels depends on the quality of the tape itself already) than you should probably check first if all the tracks of the ribbon cable from the head to RW board are OK.

Considering that playback is fine you can check even numbers of those tracks (see the picture).

If the ribbon cable is fine than it is still some traces of the RW board are damaged and you need to check accurate those traces for recording part using Service manual schematics as a help.

I do not believe that having the working playback there is a damage of the head for the recording heads (there are too narrow to the playback heads in the gap).

Can be a damage of R167 of the RW board (that prevents to overwrite correctly the tape) but very highly likely.