Vox 847 Wah power supply DC mod

[Alanford]

Hi, i'm modding my V847 Wah (true bypass, led, inductor, ....) and like to add also a filtered DC plug for power supply.

I removed the red wire of the battery clip from the multipin, and added a new wire to the + of the plug, the other + of the plug received the red battery wire and the ground was soldered to the 4th pin of the multipin. The result was a big big noise and no sound......

I searched on the net but couldn't find a wiring diagram for adding DC power to the 847 wah.

Please help!

Thank's a lot

[petemoore]

I removed the red wire of the battery clip from the multipin, and added a new wire to the + of the plug, the other + of the plug received the red battery wire and the ground was soldered to the 4th pin of the multipin. The result was a big big noise and no sound...
  when you say plug do you mean DC jack?
  If the jack is isolated, and the correct polarity DC is supplied to the circuit, it should work. Some Dc WW's let ripple through more than others...it is marked DC...? 

[Alanford]

Yes, sorry, i meant DC jack, and it's isolated. The WW is the standard Boss PSA that i use for other effects.

I was surprised when it did not work.....it seemed the easiest part of the moddding process!
I can't see what is wrong....

For filtering is a 220uF across the + poles on the dc jack correct?

Thank you!!!

[petemoore]

   Polarity...polarity !
  But yepp...'should' work and 'works' often are very very close, I think they sometimes conspire.
  Does the WW actually put out usable DC ? Does it work with other effects ?

[Alanford]

Yes, the WW works, i tried it with different pedals without problems....

Maybe should i rewire the DC mod? Just to be shure to exlude wire or solder problems.....although the solder look well done.

I really can't see the problem.

Is filtering needed for the v847?

Thank's a lot

[Alanford]

I tried rewiring but the result is the same.....

With the battery alone it works correctly, i also added a reverse switch to emulate the seagull effect on Pink Floyd Echoes that work perfectly.

Only problem is always the DC jack, as i attache the WW all goes BRRRRRRRRRRRRRRRRRRRRRRRRR big big noise

Please, if someone has a wiring diagram or can help me wiring correctly.

Thank's a lot!!!!