Fuzz Face build problem - Help : (

[beedoola]

So I built a FF using the linked vero layout below - one from the galleries here.

http://www.aronnelson.com/gallery/main.php/v/Richard-Boop-RLBJR65/album84/FFace.gif.html?g2_imageViewsIndex=1

I used most of the values listed but changed the 18k resistor to a 8.2 like most FF. I got two sets of trannies from Small Bear: All American & SINO-US

Both have tags for each set that give recommended resistor values to make Collector of Q2 4.5 volts....

The Fuzz Face works but sounds like shit, probably because the Q2 volts aren't correct. Can I just put a trimmer pot in somewhere to help dial in the proper volts? I bought the two different sets of trannies to test the different flavors of each transistor.

Is all I need a trimmer? If so, what value and how do I measure the collector of Q2 when the trimmer is installed to make sure everything is working properly?

[brett]

Hi

RE: Can I just put a trimmer pot in somewhere to help dial in the proper volts?

That's right.  Use a 25k or 50k trimmer, and connect the ends to where the collector resistor usually sits (remove the resistor first).  Connect one "end" of the trimmer to the middle (the "wiper").

Dial the trimmer while measuring the DC voltage of either +ve-to-Q2collector or -ve to Q2collector.  Adjust until the voltage is about 4, 4.5 or 5V.  Choose your favourite flavour.
good luck

[beedoola]

So using the layout above, do I remove the 18k resistor?

And how do I use a multimeter to measure the volts? where do I place the multimeter leads?

[brett]

RE: So using the layout above, do I remove the 18k resistor?

YES.

RE: And how do I use a multimeter to measure the volts? where do I place the multimeter leads?

Yes, use a digital multimeter, and put one probe (the red one if they are coloured) on the collector of Q2.  The other probe (black if they are coloured) goes to the battery -VE.
cheers

[beedoola]

Hmm, maybe I'm doing this wrong. I've tried 10, 20 and 100k trimmers and can't get the voltage to change...Keeps reading around 8.7

I took out the 18k resistor, put one leg of the trimmer in and attached the wipper to the other leg and put that in... Putting the red lead of the meter to the collector of Q2 and the black to the negative of the battery...

[oskar]

If it's boxed... maybe you didn't insert a cable in the input?

[beedoola]

No, it's not boxed but yes I've been having a cable in the input.

[oskar]

Do you get 8-9...ish voltages in the rest of the build?
If it doesn't have a path for the ground back to V- (hence my question about the cable)... you will see V+ all over the thing.
Why don't you just take like all of the voltages and post it here?   
This should be a quick fix ( famous last words...      )