Sonus 1968 Jimi Mod Fuzz - HELP

[Motterpaul]

Hi - I took on this job to add an LED to the Sonus 1968 Jimi Mod Fuzz. Important - this is a PNP pedal so it is wired with a "positive gound."

It's very hard to find schematics or pics of this pedal guts, so I hope someone here has one or has worked on one.

On the DC jack is hard wired a 490-ohm resistor, a 9v Zener diode and a 100 uf Electrolytic cap. CAN SOMEONE SHOW ME HOW THESE COMPONENTS ARE WIRED? They connect to the DC jack. I also need to see ALL of the wire connections for the guitar and amp jacks.

Adding the LED is not the problem, it is that I disassembled it and now I cannot figure out the power connections. It has both a DC jack (wired backward for PNP) and a battery connector.

 

[Hawkmoon269]

Slightly different circuit, but look at the components in blue. The capacitor and diode appear to be optional power filtering and voltage surge protection.

As far as the 490-ohm resistor (possibly it's a 470?) it's part of the circuit:

Maybe next time take some quick pictures with your phone before disassembling.

 

[Motterpaul]

Thanks, I should have taken pics and I thought about it, but the phone was not handy and I was overconfident. I also found a few schematics with the filtering upfront But the thing is I am out of practice with doing these repairs. I think I have this figured out now.

 

[Motterpaul]

I am still struggling to get this working and I feel like a fool, but...

This PNP fuzz has NKT germanium trannys and a bias pot. Does anyone know of a schematic or wiring diagram for this?

 

[R Weaver FX]

The diode is for reverse polarity protection and the electro and resistor is for noise filtering on the dc jack

 

[Motterpaul]

Thanks, I think that part is pretty well understood by me. I am struggling with remembering how to wire a standard Boss DC jack along with a battery clip in a PNP circuit. Thanks for your input though, it helps.

 

[R Weaver FX]

Thanks, I think that part is pretty well understood by me. I am struggling with remembering how to wire a standard Boss DC jack along with a battery clip in a PNP circuit. Thanks for your input though, it helps.

 

[Motterpaul]

I finally got this sorted out. The maker did not leave any schematics behind, nor did he build the pedal in any usual way. He decided that it would take Boss center negative adapters, but he built NPN so it is still reverse polarity. He decided not to make it battery/adapter compatible. You can only use it with one or the other (but inserting an input cable does not save the battery life).

It was very confusing and I just had to keep trying things until I got it going.