Trusty DCC 730 came "dead" from the attic

Hi there fellow enthousiasts

I own a DCC 730 that I bought soon after it came out. I used it a lot during my study time.

While experiencing some nostalgic vibes after watching a number of DCC related youtube video’s I decided to fetch my old and trusty DCC-730 from the attic.

Last time I checked it out was about 2 years ago, and it was working then (om most tapes I tried).
Now I appear to have an issue.

Mechanically, all is well apparently. Trying to play a DCC tape however renders a display with no playback information. (Time missing etc) and no sound. I then tried to see if the deck would find a next track (+1) . Low and behold, the machine revs up, displays time and then stops at the next track. At the start of playback however, time dissapears and … no sound.

time to try an analog tape. Hmm yes, that works! albeit a rather shabby and uninspiring sound with dropouts. After a while one of the channels breaks up and scratches. …

I decide to clean head and capstans. no effect. Then I enter service mode.

It shows a row of 8 ones after the word error. Moving through the channels with the next button gives Error 20 for each channel.

Now I have reached the point of posting this message here. I hope someone can point me to a few steps to follow to determine if the head is gone or if something else needs fixing.

There is a small board right over the head (and connected to it) , then 2 mounted vertically , behind the mechanism. Is there one of these I should focus on?

I hope some one hears this cry for help :wink:

Eager to get that 730 running again…

Hi And Welcome to the forum.

There a a few things that could be wrong;

  • The board on top of the head (read-write board) might need new smd capacitors
  • The pinch rollers usually need replacing
  • The belt could be stretched and the player now is too slow for DCC playback
  • Defective head.

Depending on your skill level you can attempt this yourself. Pinch rollers and belts are in our store and a easy test / fix.

Ralf

time to try an analog tape. Hmm yes, that works! albeit a rather shabby and uninspiring sound with dropouts. After a while one of the channels breaks up and scratches. …

That, to me, sounds very much like – best-case scenario – one or more of the electrolytic capacitors are shot. (Probably all of them.) Pinch rollers or stretched belt can cause errors and prevent digital playback due to speed variations, to be sure, but with analog playback you’d be able to hear that as wow, flutter, or just general “tape is running too slowly” pitch shift, I should think.

Worst-case scenario, of course, is that the head is defective or damaged. I’d be surprised if it just suddenly went bad from sitting untouched in the closet or attic for a couple of years, though – but I can easily see the capacitors going bad in that time, especially if the place you stored it in isn’t climate-controlled (which most attics aren’t) and your area is prone to temperature extremes in the summer or winter, high humidity, etc. Attics really aren’t good places to store expensive and temperamental high-tech equipment…

Thank you for your replies.

I will focus on the caps first. Is there a way to determine their state while still in place? They seem to look normal, with some discoloration.

As for the attic, it is indeed not climate controlled, but insulated sealed and therefore normal humidity, but yes, wit will be the warmest place in summer and slightly colder that the rest in winter. There are no better options for storing the keepers unfortunately.

Unfortunately, there’s no good way to test them while in-circuit, unless you have access to some pretty sophisticated test equipment. A basic ohmmeter can test for a dead short (zero resistance), but the other components in the circuit will make it difficult to test its actual capacitance, ESR (equivalent series resistance), and so on – and when an electrolytic capacitor starts going bad, those are the things that usually drift off-spec.

Unless @drdcc says differently (he’s one of the site’s resident experts :slight_smile: ), I believe the circuit board you should focus on is the small one just behind, and connected to, the read/write head. As far as I know, the 3rd-generation decks, which your DCC730 is, aren’t normally as prone to bad capacitors (certainly not as much as the 1st-gens, which are notorious for it), but your description of “slight discoloration” concerns me.

Any chance you could post a photo of what the board looks like? (Both sides would be best, but whichever side is visible without disconnecting and removing the board would be a starting point if you don’t want to start disassembling things just yet. :slight_smile: )

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