2 Si NPN HP like fuzz

Started by Gus, May 22, 2011, 06:05:16 PM

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kvb

don't buy the non-polar cap. you can make a non-polar cap with two electrolytics. just connect the two negative ends. the result is a cap that can accept positive flow from either direction. I don't think the schematic intends to represent the cap as being non polar. If one lead is at negative ground then there's no need for a non-polar.
I wouldn't get too hung up on tantalums either. I think sometimes they are chosen for their small size. I've heard a few stories about bad tantalums causing problems. I think most people don't worry about it either way.

as far as noise is concerned there is something strange going on but I'm not sure if that is a breadboard issue or not. It is possible that there is some high frequency feedback happening that could be cured with a 100p cap somewhere. I won't know until I build it and put it in an enclosure. Honestly that probably  won't be soon.

EATyourGuitar

yeah I had crazy noise on the breadboard. sounded like heavy distortion on the tail end of the note. when I boxed it up it was less noisy but different. like a noise floor that is really high. almost like tape noise. the 15k shunt I put in my schematic helps but totally changes the sound and behavior of the pedal. 15k shunt is a bad idea. it affects every pedal on the board cause it lets any AC running on the ground right back up into the HP Fuzz where it gets amplified. it goes through cycles where it phases itself out to near zero volume and ramps back up again. I was gonna call it a fuzz trem but after I saw what it does to the pedal board, I want to just scrap the 15k and use shielded wire and board mounted pots.

another thing that is weird about this fuzz is how the transistors are not sitting at 4.5v base and yet it is actually really clean and loud without the diodes. goes against what I know about biasing a transistor.
WWW.EATYOURGUITAR.COM <---- MY DIY STUFF

stringsthings

Quote from: EATyourGuitar on July 22, 2011, 04:16:08 PM
yeah I had crazy noise on the breadboard. sounded like heavy distortion on the tail end of the note. when I boxed it up it was less noisy but different ...

"A solderless breadboard is probably the worst noise environment you can imagine"  - amptramp


EATyourGuitar

yeah thats true but my fuzz faces work fine on the bread board. depends on the circuit. and my finished pedal was noisy too FWIW
WWW.EATYOURGUITAR.COM <---- MY DIY STUFF