Fuzzrite Build - Is this the right diagnosis?

Started by terryward, October 08, 2011, 10:15:27 PM

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terryward

Hi all,

I'm building a Fuzzrite pedal using the kit from General Guitar Gadgets.  I've made no substitutions or modifications to the schematic.  The project page is here:  http://www.generalguitargadgets.com/projects/73-fuzz-tones/257-mosrite-fuzzrite

Schematic:
http://www.generalguitargadgets.com/pdf/ggg_secf_sc_mrfr_si.pdf?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a

Layout:
http://www.generalguitargadgets.com/pdf/ggg_secf_lo_mrfr_si.pdf?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a

I'll be perfectly honest and admit I followed the layout over the schematic, this being only my second pedal build.

After wiring it all up, I had power, but when I engaged the pedal, the output volume dropped at least in half, and there was barely any fuzz to be had.  To get any amount of fuzz I really had to dig into the strings, and that was with volume and fuzz controls turned up all the way.

The transistors that came with the kit were 2N2369A, with a pinout of 1-Emitter, 2-Base, 3-Collector.

Here are the voltages on the transistors:

Q1
1       3.40
2       0.55
3       0.00

Q2
1       3.39
2       0.55
3       0.00

Now, based on Fuzzrite transistor readings I've found by searching the forum, it seems like my transistors are in backwards.  That is my readings should be


Q1
1       0.00
2       0.55
3       3.40

Q2
1       0.00
2       0.55
3       3.39

SO, does the problem I described seem to correlate with my diagnosis of reversed transistors?  I want to be sure before rotating the transistors, in case that's not actually the true problem.

Thanks!

John Lyons

The collector should show the most voltage.
So yes, looks like you have them in backwards.
Basic Audio Pedals
www.basicaudio.net/

terryward

Thanks for the reply!  I switched them around and it seems to be working properly now.

John Lyons

Basic Audio Pedals
www.basicaudio.net/