Dunlop JH 2 mod

[Kappajolly]

Hi what are the modo for increase volume and gain please? This Is my pedal:

[antonis]

Volume AND Gain..??
(are you trying to blow Jimmy's amp fuse..??) 

Volume: Try 12V power supply or lower Volume pot value..

Gain: Raise the value of first transistor's Collector resistance or place in series with it a pot wired as variable resistor..
On a second thought, it shouldn't work on an Emitter grounded amplifier.. 
(don't mess up with feedback resistor because you'll need rebiasing..)

Better read R.G.'s Fuzz Face Analysis..

[Kappajolly]

Is this mistaken "Replace the 470 ohm output resistor with 1K
Replace the 8.2K resistor at the collector of the second transistor with 18K
Replace the 1K control in the emitter of the second transistor with 2K."?

[GibsonGM]

Please provide a source for this information, so we can help, Kappa! Welcome to the forum! 

We will try to help you ... did you read R.G. Keene's "Technology of the Fuzz Face"?

[Kappajolly]

I search ed this information by this link http://www.diystompboxes.com/smfforum/index.php?topic=25408.0

But i don't understand if it is correct or not:( i don't speak very well english

[allesz]

Ciao Kappa.
The info you find should be good, but I would go with one mod at a time.
First the volume issue: you should replace the 330 Ohm (orange orange brown) resistor on the pcb with a larger value (from 470 ohm to 1k should be good).
This will increase volume, but will also change the bias of q2 a little (you may like it or not... just try).
For more gain I think it gets more complicated.... the fuzz face is quite a high gain circuit to me, I always had the opposite problem, trying to lower gain a little.

[Kappajolly]

Oh ok then i prefere first up the volume because is very limited imho, but this mod change the sound true?

[Kappajolly]

Then do i change only 330ohm and not the 8.2 with 18k?

[Kappajolly]

http://www.marshallforum.com/threads/hendrix-jh-2-fuzz-pedal-must-do-mod.37830/

[allesz]

Yes, I would first try the simple 330 ohm resistor swap.
Subbing the 8,2 K resistor for another value, or a small trim pot (and why not a full pot on the outside?), will change a lot the bias and the sound of the effect, but not necessarily increase gain.

[Kappajolly]

Ok thanks so much