No sound in or out from a D6C

I brought my d6c with me to vietnam to make some mixtapes during the holiday.
In my time of need, Sony has failed me once again, leading to rather use a JVC KD-w55 that had not been turned on since the 90's and worked flawlessly without even needing any maintenance.

I tried using an external power supply which was rated at 5V and 2000A the D6C didnt really power on, so i went and bought batteries.
It seems to react when i am plugging or unplugging a minijack in the line out; by reacting i mean an observable blimp coming from the LED when set to peak and when it's half way being unplugged. (The LED still functions normally when set to display battery status)
Other than that, mechanically everything seems good other then a bit of delay; of when i turn it off and when noises stop. There doesn't appear to be any sound/noise generated, even when taping the head, but i can't tell since the phones arent responding, neither is the mic.

From my research this is probably the mute model that needs to be replaced, and as such I have ordered a new one from our very own @Deb64
This is assuming I have an early version of the D6C; my serial number is 32258 according to the sticker.

Is there anything I should do other then replace the mute module?
Do keep in mind that my electrical skills are undeveloped and non existant, so dont ask for some crazy amp mod from ANT or anything of that sort.

Thanks in advance and have a nice day

 

Was the polarity correct ?

 

I am unsure of the polarity of the external power supply.
Here is a picture of the power supply, it is modern.


Do you think that it is this?
"Take a look at C318, 220uf, 4V. That might be the bug.
When defect, all sound is off. Your symptoms match one of my units.
When you determine that the cap C318 is busted, you can use a 16V version. There's room for it."

 

Cannot see in your pic, but the D6C uses centre negative polarity.

 

It can't be seen clearly but looks like the polarity is wrong .

 

Now that i think about it, i don't think external power has ever worked on this machine. I could be wrong

I checked and you are correct the + and - are inversed.
I am assuming then that I need to replace the capacitor as well as the muting module?

 

Is the tape still running at the right speed?

Never use any power adapter on the D6C except the original that came with it. Or better still, never use one at all.

 

That's the thing, I just can't tell without hearing. From the way the spools are moving I think it looks normal enough, I'll upload pictures and a video once I'm done with my flight.

 

Just changed muting module yet nothing changed.

While I was inside I also took a look at a capacitor, that was mentioned in a tapeheads thread. The capacitor in my machine appears to have already been changed from the 4v stock one to a 220 microfarad 16v one.
I am unsure of what to do.
Speed appears correct.

 

Do you still have the 11V supply from the DC - DC convertor? Check the voltage on Pin 3 of the mute module, which should be 11V. The pins on the mute module are numbered 1 to 7 with pin 5 missing.
If there is no 11V then your mic and line recording pre-amps won't work, neither will the pre-eq amplifier off the playback heads.
On a D6, the motor will run too fast if there is no 11v rail, but the motor drive circuit on the D6C is different and does not rely on the 11V rail.

If your D6C has had the power connected with the wrong polarity, then it may have damaged the DC - DC convertor? According to Mihokm this is quite a common problem and he has posted information on how to repair it here:

WM-D6C DC-DC converter fixed