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DIY Stompboxes => Building your own stompbox => Topic started by: dam28 on May 05, 2011, 05:38:37 PM

Title: Yet another FuzzFace problem.
Post by: dam28 on May 05, 2011, 05:38:37 PM
So, I built the following fuzz face of vero board...

http://www.aronnelson.com/gallery/main.php/v/DRAGONFLY-LAYOUTS_0/album18/album144/SILICON_FF_VERO_001.gif.html

Its works and sounds nice if it wasn't for the REALLY loud and annoying whistle / noise. It gets worse the higher the fuzz pot is turned up. The circuit also goes into oscillation when the input (guitar) is unplug.

I know this is a question everybody probably asks but ive built it, it sounds nice but its unusable because of the noise! Please help!

-D
Title: Re: Yet another FuzzFace problem.
Post by: R.G. on May 05, 2011, 07:16:04 PM
This is nearly always either
1) Lack of clean power supply and/or grounding
2) Mistakes in wiring/routing.

Or both.

For 1, install a 47uF to 1000uF electro cap in parallel with a 0.1uF ceramic across ground and the power supply on the PCB. For 2, figure out how to make every single wire as short and direct as possible.

There are others, but these are my first responses.
Title: Re: Yet another FuzzFace problem.
Post by: dam28 on May 05, 2011, 07:34:28 PM
I tried number 2 but ill give number one a go! Thanks for your help :)
Title: Re: Yet another FuzzFace problem.
Post by: LucifersTrip on May 06, 2011, 03:58:22 AM
Quote from: dam28 on May 05, 2011, 05:38:37 PM
It gets worse the higher the fuzz pot is turned up.

This sounds like what happens with a higher gain silicon FF.  Try a small cap 100 - 200 pf across BC of Q1