MP Fire Red Fuzz output

[roccster]

Hi all!

New to the forum and fairly new to pedal building. The MP Fire Red Fuzz is the 3rd pedal I built.
Everything seems to be working ok, except I think the output volume is a bit low.
I basicly need to crank it to match the dry input volume.
Any ideas?

Cheers!!

/ Richard

[IvIark]

There should be plenty of volume, post you voltage at each transistor pin and we can see if anything looks obviously wrong

[roccster]

Ok here we go:

Q1
C: 3,93V
B: 0,637V
E: 30,00mV

Q2
C: 4,13V
B: 0,660V
E: 40mV

Q3
C: 3,9V
B: 0,645V
E: 0,42mV

Q4
D: 380mV
G: 0,660V
S: 380mV

Q5
D: 0,660V
G: 330mV
S: 0,660V

Q6
G: 0
D: 2,927V
S: 2,64V

brgds

/ Richard

[roccster]

Oh and I noticed that the loss of output is when i have the tone at 10-13 o clock. When the tone is rolled back or full the volume is as it should.

[Frank_NH]

Check your volume pot - perhaps it's defective?  Or you have a log pot (versus linear)?

[roccster]

Ok ill check that just to be sure.
Is there anyway to verify a pots function?

[dbat69]

The easiest way is to measure the resistance at various points around the sweep of the pot.  If it is linear, the resistance will change at a constant rate.  e.g. if the pot is a 100k linear, at 1/4 turn it will read 25k, 1/2 turn it will read 50k and at 3/4 turn it will be 75k.
If it is a log pot there will be slow rate of change at one end of the sweep and a much faster rate for the best part of the sweep