Hi all!

I recently acquired a mint looking wm-d6c.

i tried it with a fresh set of batteries. The motor seems to work fine since the tape turns. But i hear only very faint sound over the headphone out and nothing at all from line out.

Is this a known problem with a easy fix?

I have a little bit of DIY experience, so with the right guidance i might be able to fix it.

or are there any known technicians in Europe which still work on these units?

any help would be appreciated.

I have also a D6C with the same problem ,speed is ok but no sound, a search  on the web led toa forum where a guy sugested that the problem was the dc-dc converter which drives the audio circuits.Dc-dc converter is a litle can sealed component with a tiny PCB in it which steps up the 6v battery voltage to something about 10v.The same guy tryed a 9v in place of the dc-dc converter and voila the machine worked fine .I tryed the same experiment myself ,with help from the service manual and i can confirm it works. Unfortunatly you can't find dc-dc converter as a spare part today and one  i saw lately on ebay was a 38euro buy it now item.I even opened the dc-dc converter to my D6C just to find some fried componets in it but i can't replace them because service manual lists the converter as a single component.         

So you can use this fine machine for some great recordings with this method but it will not be portable.

Hope this helps.

i measured the orange wire coming from the DC converter board with 11,3 V DC.

the SM says 10,8V so i guess my DC DC converter i fine.

It seems dc-dc converter is ok and that's good news!

I would proceed with most common cheks like volume control resistor,phone jacks,allthough no sound from audio out makes me think maybe there is a capacitor problem in audio amplifier.

since both line and headphone out are affected i think that it is indeed some capacitor problem. any ideas which caps to check first?

i tried recording to see if that works at least. While the record function basically works, i have a lot of distortion with record level set so that 0db would light occasionally.

further i noticed that the counter doesn't work.

You can start by checking  c135,c136,c306 these are feeding line amp ic301 which in turn suplies audio signal to headphone amp ic102 AND line out.These are for L-chanel.

If you turn volume to max and you can hear some amplifier noise and fainted audio signal maybe the problem lays to these components.

Update:to test recording function is a good idea as the recording button operates a sliding switch (s301) that selects play/rec mode.

Maybe it's stuck , dirty or defect .Sometimes if you operate alternatively play and rec bu

ttons functions again.Still you have to clean it or replace  it so its trustworthy.

The counter must be simple fix replacing the belt that drives it.

Note:my SM is from 1984 so there may be diferencies to yours.