Carlsbro Fuzz tone pedal 1966

[Cloudhopxx]

Has anyone successfully cloned this ? There is a schematic on the internet and ive copied it exactly ….it doesnt work. My OC71s are tested and are good. Ive seen various amendments to this circuit and people have got it working ….but Im stuck. There must be faults on the schematics ? Ive sussed the capacitor values and changed those . Still no joy.
I had the original back in 1968 but over the years it fell to pieces …if only i had kept them. The best fuzz box i ever used. More overdrive than fuzz.

 

[SillyOctpuss]

You're better off checking out freestompboxes and pedalpcb for help with this.

Out of curiosity what schematic did you use and what did you build it on? Pcb or vero? What fault are you getting? No sound or sound but no fuzz? If you have the hfe and leakage and took bias readings for the transistor voltages that would help too.

 

[Cloudhopxx]

Thanks for your reply SillyOct. Someone out there cares !!!

I started with a double tag circuit via Amplified Parts. That didnt work. Had two goes …nope. Then i tried the original Carlsbro schematic and drew a copper board pattern exact to the circuit. Nope. Didnt work.
There are a couple of veroboard strip board versions with slight variations on connections and componenets. I used these for experiments but still no joy.

Right now the signal passes thru the circuit with or without battery . It buzzes and crackles to buggery. Their is some overdrive (I think) but hard to tell. Vol and attack controls work but you cant say its a working module. In fact i still dont really know if the battery connections are reversed as some circuits say 9v , others say -9v.

I would just love one definitive schematic that has been verified and has been made and works correctly. Not too up on taking transistor readings …with such a small circuit the blasted thing should be working. Ill try the free stomp box site …thanks for that tip .