Marantz DD-82 plays with issues digital works with some dropouts, analog plays one channel

Hi DCC forum, I have a Marantz DD-82 1st generation recorder. I’m hoping you can help me get this machine working properly.

I’ve tried it with analog tapes, it has low level playback without distortion, slight tape wobble, normal speed.

I managed to get a single DCC digital tape which plays back song recordings (done I assume via digital ) at normal levels with led level displaying, there is some slight distortion & some dropouts.

I’ve cleaned the heads, it made a slight difference with analog playback. . I am going to recap the head board but I’m wondering if I need to replace the capstan belt at the same time.

I was thinking of wiping the BASF DDC tape with a bulk eraser & trying to record via digital inputs & the analog inputs? As it is an old tape it’s possible some of the data might be missing. I don’t have another DCC tape to try at present.

Also I was wondering if there is any way for the error correction data to be displayed when playing back.

Regards JK

Welcome to the forum! Here is a good explaination of the service mode to view error correction data by @Easy-Rider. Replacing belts and pinch rollers is also a good idea. I suggest getting any prerecorded tape that is known to be good to properly judge.

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Thanks for the welcome Max.

I couldn’t get the DD-82 to go into service mode to check the error correction data.

I’ve just tried recording, the tape plays along in record mode & leds monitor level, analog input sounds at the output, plus optical input from a CD player plays out thought the D/A converters without issues.

Tape playback has no audio recorded from the optical nor analog inputs.

I’m going to watch the video a few times, before I recap the PCB board inside the head assembly.

Regards JK

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Got the 2nd PCB out, looks like someone has been here before & wrecked the pads & traces, then replaced the 4 X 68uf caps instead with 47uf’s,

I can’t get any readings from the 4 X 10uf’s , the other two caps test fine.

I’ll have a go with & try some leaded caps, as the pads underneath are in very bad shape.

This is the best I can do, but it’s totally wrecked, I’ll give it a try later on.

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The digital board (under the cover) has some bad corrosion from leaking caps, I’ve cleaned it with Isoprophyl alcohol but it’s still rough.

I’ve noticed one cap has a lifted trace pad on the corner of the PCB. I have replaced all the rest apart from one bipolar cap which is on order.

It’s cap C429 10uf 16V negative pad is OK, The C429 positive pad is connected to L421 100uH inductor looking at the schematic?

Anyway I managed to expose the trace & made the connection & fitted the last cap in place.

I’ve just now got improved digital sound playback with less drop outs than before, some songs on this previously recorded DCC tape are actually playing without any errors. .

But still when I record it doesn’t playback at all. I’ll see if I can get some other DCC tapes to try out.

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This is a fault that I read often… perhaps because of the new caps the write current must be ajusted… @drdcc might have an answer, Ralf did you encounter this problem? Playing right but not recording at all?

Usually the read-write amp has a problem, but it could also be the potentiometer to adjust the current.

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I finally got into SERVICE mode as suggested previously by Max above, doesn’t look good.

In ALL ERR RATE mode he DCC tape plays back with some drop outs, displaying F on the 7th digit LED. The 6th digit LED fluctuates between 0-1-2 sometimes up to 4. All the rest are 0 display.

So user recorded digital tape plays back with some dropouts, analog cassette plays full level but only one channel, we have no output playing from recording. :frowning_face:

I need a pre recorded music tape to confirm this but I’m assuming the heads are faulty?

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One channel seems dead, one has problems. That is why you are getting the dropouts. A pre recorded might do a little bit better, but either the head or amp has a problem.

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I’m completely agree with Ralf.

To find out if it’s the read amp chip you have to check input voltages on the channel lines (0.6V) OR swap the board if you have a spare one.

The factory prerecorded tape give usually better results but you have still one damaged channel. You still get the sound thanks to the error correction but if the next channel dies, the sound disappears.