Breadboarding a Fuzz Face (Hornet) issues

[Pmelius]

Here's the schematic - http://www.diystompboxes.com/pedals/hornet.jpg

I've spent countless hours the last two days breadboarding this project with tested transistors/resistors from Small Bear and I'm about to pull my hair out.  No matter what I do, all this circuit does is pass clean signal and I've come to the conclusion that I'm just going crazy and missing something obvious.  I have removed both potentiometers for the sake of simplification.  The 5k pot is now a 4.7k resistor and the 500k volume pot is just removed and the .01 goes straight to the output jack.

I have started from scratch multiple times, referenced other fuzz face schems, tried other transistors, tried different resistor values, etc.

Please help me before I lose it!

[Mr.Kite]

I'm not an expert, but maybe try to over-simplify it: replace all the trim pots with fixed resistors, it is a "standard" FF circuit, it should work (fuzz)...if not, check all your connections and maybe restart from the beginning...

[Mr.Kite]

Uh, you've already done that! Re-check all your connections, be sure that whatever goes to ground actually goes to ground, and whatever goes to the battery + goes effectively to the battery plus...sometimes I miss the right "line" with components in series, re-check all of those too!

[thermionix]

Check continuity all the way along the + and - power rails on the breadboard.  Yours is different from mine, which has a single gap in the middle that needs jumpers.  I don't know if yours is continuous or needs jumpers at every gap, or what.  I would just measure for 9VDC across the rails at the far end from where your battery is hooked up.  Hope that makes sense.

[Pmelius]

Check continuity all the way along the + and - power rails on the breadboard.  Yours is different from mine, which has a single gap in the middle that needs jumpers.  I don't know if yours is continuous or needs jumpers at every gap, or what.  I would just measure for 9VDC across the rails at the far end from where your battery is hooked up.  Hope that makes sense.

I measured 8 something volts dc on the legs of the resistors I have coming out of my V+ rail.  That doesn't seem to be my problem.

Uh, you've already done that! Re-check all your connections, be sure that whatever goes to ground actually goes to ground, and whatever goes to the battery + goes effectively to the battery plus...sometimes I miss the right "line" with components in series, re-check all of those too!

The circuit only has 2 points at V+ and 4 points to ground, excluding jacks. I've wiggled everything all the hell around and I'm still just getting clean signal.   

[Pmelius]

The plus side to all of this is that I now can recall a fuzz face schematic from memory with no problems! 

[patrick398]

The output jack wires aren't the wrong way round are they? I can't tell the colours apart in those photos. I'm sure you've already checked that but just wanted to make sure

[Pmelius]

The output jack wires aren't the wrong way round are they? I can't tell the colours apart in those photos. I'm sure you've already checked that but just wanted to make sure

I actually, foolishly, wired them with opposite color coding not paying attention, but the jacks are definitely in correctly.

[patrick398]

Can't see anything obviously out of place, a couple of things are obscured but generally looks ok connection wise. What transistors are you using? Definitely got them orientated correctly? I'd check that, then also double check the values of the resistors. A few times i've been going nuts when something isn't working and it turned out i had a 3M3 resistor wired instead of a 3K3...although the pack was mislabelled so not totally my fault 

[Pmelius]

Can't see anything obviously out of place, a couple of things are obscured but generally looks ok connection wise. What transistors are you using? Definitely got them orientated correctly? I'd check that, then also double check the values of the resistors. A few times i've been going nuts when something isn't working at it turned out i had a 3M3 resistor wired instead of a 3K3...although the pack was mislabelled so not totally my fault 

Q1 - Ge 2n281
Q2 - Si 2n5087

Like I said these were also tested from Small Bear and came with resistors which they used in their circuit, which especially makes me scratch my head.

I have a cool little transistor tester which gives me the pinout and I've been double triple checking this the whole time.  I'm going to revisit resistor values...this is a good thought.

Only thing about it is that I've tried playing with almost all of the resistor values to see if it even affects the circuit and the only thing I've successfully made it do is make the whole thing more quiet.  Just quiet clean tone hahaha.

[Pmelius]

Here's a better pic just for fun 

[patrick398]

Again it's hard to see properly but is that 47uf cap going to ground in contact with the 1k going to 9v? If so you'll be shorting Q2 collector. Where they overlap it looks like they could be touching

[Pmelius]

Again it's hard to see properly but is that 47uf cap going to ground in contact with the 1k going to 9v? If so you'll be shorting Q2 collector. Where they overlap it looks like they could be touching

Nope, this is just an illusion in the photo.  Definitely none of my leads are touching outside of their terminals.

[patrick398]

Can you take measurements of the transistors with you multimeter? Confirm that the collector voltages are similar to the schematic? 0.822v Q1, 3.6v Q2

[Pmelius]

I questioned the reliability of my transistor tester and threw the transistors in different orientations and realized it does not give me accurate pinouts.  My Q2 Si was installed correctly but I'm having trouble finding a reliable pinout of the Q1 Ge 2n281 online.  The one pinout I found gives me no output in that orientation, reversed from what I had it gives me identical to my original results.

Doing some more digging on a correct pinout for that now.

[Pmelius]

Can you take measurements of the transistors with you multimeter? Confirm that the collector voltages are similar to the schematic? 0.822v Q1, 3.6v Q2

I'm actually getting 5.1 on q2 and 4.1 on q1

[patrick398]

Q1 collector seems high...i'm not expert and it's been a long time since i built a fuzz face but i'm sure it needs to be nearer 1v. You could try increasing the 22k resistor going to 9v but i honestly don't know if that'll fix your issue

[Pmelius]

I've determined the correct pinout for q1 and it was installed correctly, so nothing has changed there.

[Pmelius]

Q1 collector seems high...i'm not expert and it's been a long time since i built a fuzz face but i'm sure it needs to be nearer 1v. You could try increasing the 22k resistor going to 9v but i honestly don't know if that'll fix your issue

Just tried 100k which gives me closer to ~2v with no change in symptoms

[Electric Warrior]

Q1 collector seems high...i'm not expert and it's been a long time since i built a fuzz face but i'm sure it needs to be nearer 1v. You could try increasing the 22k resistor going to 9v but i honestly don't know if that'll fix your issue

It needs to come down, but not by tweaking the resistor. This is way too far off to be a simple bias problem. Something else must be wrong with it.