new guy with fuzz face problem

[sonicforensics]

hello new to the board, I've been poking around this sight for a while and you guys seem really knowledgeable. I just built a silicon fuzz face off of the dragonfly layout page. I plugged it in and only got sound in my guitars parallel neck/bridge setting, series neck/bridge:nothing. tried a different guitar with the same results. I then put a new tube screamer in front of it even with the ts off, the fuzz face works like it's supposed to. I've built around 10 different pedals and have never come across this. The only significant changes I made were a 470 resistor instead of the 330 and used a 1k rev log pot for the fuzz control as I didn't have a linear around. I also added an indicator led.
I have checked, double checked and tripple checked the layout. If anyone could lend me some advice that would be much appreciated.
Thanks ahead of time

[Alex C]

Hello, and welcome to the forum. 

That sounds like a strange problem. 
Could you tell us a little more about the details?  It might help in finding what's wrong.

What kind of guitar did you use, what type of pickups, and what was the other guitar- does it also have the parallel/series setting?
Does this happen at all guitar volume levels?
At all effect volume/fuzz levels?
Does it work with the Tube Screamer on?
With the TS boosting the signal?

Does "no sound" mean absolutely nothing, or some hiss/hum, or faint noises?
Is the Tube Screamer true bypass or buffered?


Like you said, there are a lot of knowledgeable people here who are more than willing to help- it's a great place.  Again, welcome, and have fun!

-Alex

[aron]

If I had to guess, it's some sort of biasing problem. I'm not sure how, but plugging in that TS affects the bias. Very strange.

See if this helps you any:

http://www.diystompboxes.com/smfforum/index.php?topic=29816.0

[Gus]

If I understand the post correctly
The FF works with a TS but not with the guitar?

What is different?  The TS is buffered and has a output cap.  I would check the input cap area of the FF maybe the cap is shorted with a solder bridge or bad?

[sonicforensics]

Thanks everybody for responding. I read the debugging thread, I don't have time right now to take a reading on all my voltages, but I will this weekend and will post them then. As far as the input cap goes I've already changed that out as that was one of my first thoughts. With the new one, same results all solder connections look good under a 10x magnifying glass. I'll trace the circuit properly with a meter this weekend. The guitars:#1: telecaster, single coil texas specials wired to a fender 4-way switch, switch settings: bridge, bridge/neck parallel, neck, bridge/neck series. #2: epiphone dot: humbuckers bridge SD custom custom, neck SD pearly gates, wired traditionally to a 3-way switch: bridge, bridge/neck parallel, neck. Without the tube screamer in front: very, very faint sound not crackly just extremely low with pickups on either guitar set to single pickup settings or the tele's neck/bridge series setting. By the way the TS is a TS9-DX, I also tried a DS-1, same results. TS or DS-1 before the fuzz face:sounds good at all guitar settings with both guitars even with the TS or DS-1 turned off. Another thing I noticed is a sizeable volume drop if the TS or DS-1 is turned on even with volume controls maxed. The guitars are known to be good and so are the manufactured pedals and work just fine without the fuzz face in the mix. I know I probably repeated myself and may have been a bit long winded. That being said I'll be back this weekend with some numbers. Thanks again everyone. This is such a cool forum.