I have acquired a lovely DD9 which sounds amazing and works super, unless you move it and then it is intermittent. The play stops. Sometimes if you wiggle it comes on but mostly it cuts out. Is this a known problem and can it be repaired? Although it is good for home use I wanted it to use it as a daily walkman. Sometimes this does not happen, but other times when you push play it works but by the time you have put it into a pocket it has cut out. Obviously this is impractical when using it for commuting. Any help would be appreciated.

If it can't be repaired then does anyone want to swap it for a repaired DC2. It comes with the original instruction book and the walkman looks pristine.

Agentorange & Isolator42 will know

Hmmm, a tricky one, can't say I've come across this issue.

Dottor is an expert in the DD9 field.

Thx for the vote of confidence Nicolle, but I'm no DD9 expert, having only laid hands on one for a few months & failed to fix it!

Sounds like a power issue to me - maybe check the battery terminals & the connections from the battery terminals to the board?

Since the DD9 is logic controlled, any slight loss of power will cut it off (unlike mechanical units with push buttons).

Likely a poor connection in the battery compartment as you said.
Also look out for circuits that stop the unit when the door is open.

I have 2 dd9.. i wish sombody could build me a working one out of the two....

Thank you all for your replies. It is a power issue from the internal battery compartment. I have tried it with an external power supply and it does not cut out. Thats good as I was worried that it may have been a break in the cable from the logic controls to the walkman. Does anyone have the service manual for the DD9 as I now need to work out how to take it apart.

Thanks to everyone for helping.

I have realized that the problem could be as simple as the type of battery I am using. I was using an 'own brand' AA battery. I have tried two other types and this problem does not happen. I have noticed that the 'own brand' battery appears to be slightly smaller.  It could be as simple as the contacts having worn over time. I still want to take it apart and look at the contacts. I am also going to buy some Gumstick batteries and see if these work well.

I will keep you informed.

Thanks

If the contacts are bendable, they may have been pushed in over time, and you could try bending them out a little.

Happy days. I used the walkman successfully today with another battery and had no problems. I still want to take it apart and look at the contacts.

Thanks for everyones assistance.

Have you found a service manual yet?

Hi,

I was just about to post a thread about the DD9 when I saw this one. I have two DD9s, one of which works great, the other is giving me a bit of a headache. When I first acquired it, it played okay, but seemed to have trouble reversing at times. You could hear some grinding inside. Now, about half the time it plays and reverses properly the other half it will play for a few seconds and then start fast forwarding or rewinding for a few seconds and then shut off. It will also reverse at times, play a few seconds and then shut off.

My initial thought was that the logic circuit wasn't getting the proper feedback from the switches/sensor which was causing it to react as if the transition from forward to reverse, or vice-versa, had failed. Last night I opened the unit and checked the position switches and optical sensor. There are no visible problems or issues. The unit is very clean inside and out.

What is totally unfortunate is that the optical sensors are mounted on the top side of the bottom board. This means you can't operate the unit with the board removed so you could maybe see what the problem is.

I put the unit back together after staring at it for an hour with no clear idea for a fix. I thought about selling it for parts, but it's such a great unit, I hate to let it go. I decided to check with you guys to see if you may have any ideas for me.

I do have a service manual if you still need one.

Thanks,
Cameron

Sorry to hear about your problems Cameron. Thank you all for the offer but I have acquired the service manual. For me it was just an odd issue of battery size and the power cutting out. I have used it for mu commute for the last two days and all is OK.

Thanks

Hmm, about working on the DD9 with the board removed. In some of my service manuals for other models, there are pads you can bridge to disable the optical sensor in repair mode. Does the DD9 have any such feature? (Don't have my manuals with me right now).

Alternatively, you can supply a square wave to the optical sensors (read about it in a different manual) to fool the optical sensor.

Great tip! I suppose I should have spent a little time staring at the service manual instead of the Walkman.

I'm going to open it up again and try this. Do you recall which manual has details on the square wave? I have a B&K signal generator, but would like to know the optimal voltage and timing.

Thanks,
Cameron

What do you know, I just checked my DD9 service manual and it has instructions for square wave input on page 3. 20hz, 2.5v. Sony service manuals are so detailed compared to my crappy Aiwa ones.

I know the WM-7 can be bridged to disable the optical sensor.

Now all i need to do is get a DD9.

Awesome! I'm going to tear back into it tomorrow night. Speaking of Aiwa manuals, you wouldn't happen to have one for the HS-JX707 would you? It's the talking one and mine has an issue similar to the DD9 where it acts up when reversing.

Thanks,
Cameron