Trying to get fuzz box to work...but its not quite there, need help

[tungngruv]

I fixed the drawing. The pink line is a jumper, it can't touch the green line under it. Sorry about that. Also, make sure you check the switch wiring compared to the link.
http://www.diystompboxes.com/pedals/DPDT.gif

[Joecool85]

Well, just went over everything, all of it is wired great...including the switch.  Wondering if maybe I messed up my germaniums my having the polarity messed up at the beginning.  Radioshack has 2n3904s and 2n3906s, those are both pnps, could I swap in those or would that not work right?

[Joecool85]

Also, off Q1's emitter, it should have full power (and it does) because I had the negative connected to the neg on the power and was running the positive to points to check for power.

**edit**
If I test the other way, only Q2's emitter gets anything.  Thats why I had posted (-) or (+) next to my findings in those posts.  Is that bad?  Should the trannies be getting neg through them?

**edit again**
I think my next step will be to socket the resistors/trannies so that I can actually swap things out without soldering all the time.  Then try some stuff.  Like those 2n3906s or something.  I still think I might have fried my germaniums.   Is there a way to test that?

[tungngruv]

I'm at work now, so I'll try to help when I can. If you get a good tone from it, it is working right, just have to resolve the volume issue. If it's possible, can you take one more pic of the underside of your board, up close (like your first pic)? Also, I know the trannies are supposed to be fragile, but I've done some stupid suff and all of mine survived.

The pedal is "working", right? Just no volume?

I always solder in Q1 (2n3906) and socket the germanium. Also, if all else fails, you can rebuild the Easy Face layout at my site or Runoffgroove.com  Multi Face with the parts you have, but that would be a last resort.

Also, off Q1's emitter, it should have full power (and it does) because I had the negative connected to the neg on the power and was running the positive to points to check for power.

Most of my fuzzes are PNP and I get 0 volts off of Q1's emitter. Also, looking at your voltages, every pin was getting close to 9 volts, weren't they?

Also, off Q1's emitter, it should have full power (and it does) because I had the negative connected to the neg on the power and was running the positive to points to check for power.

But Q1's emitter is connected to ground , and you are building a "positive" ground fuzz. Is it possible to just use a reg battery connector till you get it working?

Radioshack has 2n3904s and 2n3906s, those are both pnps, could I swap in those or would that not work right?

2n3906 yes, 2n3904 is NPN

Also, this is right from a current thread that has  a similar fuzz issue. Here are Martymarts voltages:

Q1 
C 1.97v
B 0.67v
E 0.0v
Q2
C 4.79v ( this is about right and sounds good used a 10k trim pot here from 9v)
B 1.97v ( same as Q1's collector as they are directly connected )
E 1.24v ( this will change depending on where the "fuzz" pot is, this is at MAX fuzz setting

And here is the thread:
http://www.diystompboxes.com/smfforum/index.php?topic=39353.0

[Joecool85]

Its not now that I have my caps in the right direction and everything.  If I crank my amp way up it has ok sound and then fades out and then ok sound and then fades out etc.  It is a positive ground FF circuit.  I could connect it to a regular battery till I get it working, but there will be no difference.  I'm thinking maybe I will grab another board (since mine is getting a little messy) and use the resistors that smallbearelec sent me, socket the trannies and see what happens.  If that doesn't work I might plug in a couple 2n3906s and see what happens.

[tungngruv]

If you do rebuild it, try socketing the trannies. I still think your germaniums are ok though! Also, if you do rebuild, use a 10K trim instead of the 8.2K. You can really dial in your 4.5 volts using that. Also, look up your trannie data sheets to make sure they are PNP. Look also at Runoffgrooves.com multi face. Pretty clear explanation and pictures, just sub your parts in.
http://runoffgroove.com/multiface.html

[Joecool85]

Yeah, like I said, I think I'll socket the trannies and use the resistors that came with it. 

IE-  Instead of what I have right now
33k     33k
670     470
10k     8.2k
120k    100k

Basically the set that came with it has more resistance, but since the original schematic didn't use those values, I didn't either.  Now that it doesn't work, and evidently these pnps were "matched" using the resistors that came with them, I'll try that and see what happens.

[petemoore]

  Here's how I test.
  stick the transistor in question in a FF [with PNP or NPN, depending on what you have of course] that I know works.
  Stick the transistor in the Hfe checker of the DMM, this tells gain story, nothing about leakage, but...will tell if it's at least amplifying.
  Do the B/E diode check just as you would check a diode, less conclusive than Hfe or circuit test...I use this mainly to determine whether I have a PNP or NPN, and where the emitter is.

[Joecool85]

What if you don't have a working fuzz pedal or a Hfe checker?

[tungngruv]

It might be a good idea to carefully unsolder all the parts, get a new board and try it again. I would suggest the you actually run the component leads to each component, use a socket for at least the germanium and connect the wires through the board to the wire between componenets. If a component lead is too short, just make a bridge using parts of the component leads you have already cut. It's very close to the Easy Face layout on my site and do yourself a favor and use the 10K trim ($1.29 at radio shack if you don't already have one). Also, know your pinouts of the trannies you are using . You could probably use a 2n3906 for Q1 and then make a socket for Q2, that way you could swap the trannies to make sure the right one is in the right place. Steve usually marks the hfe on the outside of the bag they come in. That 10K trim pot is unbelievably useful for dialing in the right volts and you can see how to hook it up on my layout page or at runoffgroove.com under the multi face. Here is a pic of my Dinosaur fuzz I just finished using the component leads to connect each component, sorry about the bad camera focus.

http://www.picturetrail.com/gallery/view?p=999&gid=8800236&uid=4033194&members=1

[Joecool85]

What exactly is a 10k trim?  Would this take over where the 8.2k resistor is now or is this in addition to?  Excuse my ignorance.

[tungngruv]

A 10K "trim pot".
http://www.radioshack.com/product/index.jsp?productId=2062301&cp=2032058.2032230.2032275&parentPage=family

You use it as an adjustable resistor so you can use a small screwdriver and vary the resistance until you reach 4.5v on the collector. You really need to check out the runoffgroove.com article on the multi face just to see how you can perf up a circuit and take a look at the trim pot.

http://runoffgroove.com/multiface.html

[Joecool85]

Yeah...I guess the plan right now is to just get some sockets, a new board, re-do it socketing in the trannies and put in the set of resistors that came with them and see what happens.  Not sure exactly when all this will happen.  Being a college student and classes end in 2 weeks leaves me a little busy lol.

[tungngruv]

You know, you could literally throw the multi face together with radio shack parts and it sounds killer! Really. Then put your germanium together as time permits.

Also, check your email.

[Joecool85]

I dunno about the multiface, while it looks cool, I think if I'm going to take a break on my fuzzface pedal I might make a bazz fuzz pedal:
http://home-wrecker.com/bazz.html

Super easy and sounds pretty different.

[Joecool85]

I GOT IT WORKING!!!!!!!!!!!!!

It sounds great too.  Basically I redid the whole thing on a new board and socketed the ge's and now it works.  Go me!

Next up: Bazz Fuzz

[tungngruv]

That is awesome news!!!! Glad you got it working!