NEED HELP Breadboarding a Silicon Fuzz Face Pedal

Started by bonzoboi, January 26, 2017, 02:19:03 PM

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Ruptor

Quote from: duck_arse on February 01, 2017, 09:10:56 AMruptor - if you haven't already, can you post the circuit diagram you are working from, please,
DA! I think you have your wires crossed. :icon_lol: Bonzoboi has posted the circuit and a picture of the breadboard in first post. I was just trying to help fault find with the suggestion the 8K2 junction looks suspect and with my simulator rough voltages using 2N3904 transistors. :icon_rolleyes:

duck_arse

ruptor! get to it - do those measures!

sorry, Bonzoboi, now we are on page three, page one is soooo last eweek, so my circuit request is again valid.
You hold the small basket while I strain the gnat.

Ruptor

Quote from: duck_arse on February 01, 2017, 10:10:04 AMruptor! get to it - do those measures!
I don't need to because I have built a working FET based FuzzFace as on my thread here
http://www.diystompboxes.com/smfforum/index.php?topic=116629.0
Bonzoboi is the one building the breadboard unit on this thread.

bonzoboi

Hey everyone, once again, thanks so much for your responses and support.
Just wanted to give an update on my progress, and inquire about some further steps:

Right now, I'm going to test my breadboard to make sure all of the rails work, and I've already tested my components and every has the correct value. I have a feeling that the breadboard isn't the problem, but hey, maybe it is, we'll see. But I'm getting to the point where I just feel really lost in terms of where I should go next to test, modify, or troubleshoot this thing. I've followed the wiring layout at http://diy.smallbearelec.com/HowTos/BreadboardSiFF/BreadboardSiFF.htm exactly as it was shown, so is it maybe just an issue with this circuit layout? I know they said on the page that it was tested to work, but I'm having my doubts. Someone also recommended earlier that I try an LPB1 circuit instead? Like would it be a good idea for me, as a beginner in pedal construction, to try a simpler circuit? Sorry to appear kind of helpless, but I'm just feeling worn down by the troubleshooting process, and I REALLY want to get this thing to work.

Also, here are the pictures I've taken of my breadboard, would it be helpful if I posted other pictures?

Over-view: http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/20170127_140911.jpg.html
Closer over-view: http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/20170127_140957.jpg.html
Side-view: http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/20170127_141021.jpg.html

bonzoboi

As I expected, my breadboard is all good across every rail.

bonzoboi

I also went through the circuit and probed every connection between components (because I figured out how to do resistance testing correctly, I was doing it incorrectly before), and everything seems to have a connection. Still feeling stumped...

Ruptor

Try wiring the breadboard like the schematic with the positive rail at the top and the negative on the bottom. It would reduce the connections and make it easier to follow and would only take a few minutes.

duck_arse

I still want transistor type numbers, but I'd also agree with build an lpb. tear down the parts on yr bb, turn it around 180 degrees, just for kiks, and then build two lpb's using those transistors. if you can get them to work, should be a doddle on the FF thereafter.
You hold the small basket while I strain the gnat.

bonzoboi

@Ruptor I'll try that out today.

@duck_arse My transistors are silicon 2N9304 transistors. That info as well as other components specifics can be found on the 1st page of the thread where I posted all of my circuit/breadboard info. The webpage I am working from said the these transistors should work with this breadboard project. And other sources that have provided schematics and project details for the Fuzz Face have said that these transistors work.

bonzoboi

I tried breadboarding this with the positive rail at the top and the negative rail at the bottom, and this time, I still didn't pass a signal from the guitar, and whenever I touched the guitar or the output with my hand I got a loud buzzing, as if there was something that wasn't grounded on the circuit. I made sure to test continuity with my multimeter too and everything was good. I'm concerned that maybe my 1K pot is causing some issues? It's a 1K linear taper pot, as opposed to the 1K reverse audio pot recommended on the webpage I've been following. Could this be a source of the issue? I'm going to see if I have the parts to build an LPB-1, but would still appreciate pieces of advice for this, because I'm getting to the point where I'm going to have to set it aside soon, since I've spent at least a month trying to get this breadboarded circuit to work, and I feel like I'm wasting my time at this point since I feel like I've made all of the adjustments that I could. I'm not trying to give up, because I want this to work, but I feel like I've been going nowhere lately.

rutabaga bob

The pot's taper wouldn't cause you any issues like you describe...hang in there!
Life is just a series of obstacles preventing you from taking a nap...

"I can't resist a filter" - Kipper

bonzoboi

Hey everyone, so I breadboarded an LPB-1, and unfortunately it did not work.
I'm going to start a new thread to work on the LPB-1, and put this project on hold, unless anyone can notice something in the pictures/voltages I've posted thus far.
Thanks for all the help, it has been greatly appreciated.

Ruptor

#52
Where is a picture of the latest simplified breadboard? You can stick 1K and 500K resistors in place of the Pots to make things really simple. I did this on the simulator because I couldn't be bothered getting the simulator Pots to work. :)
What is LPB? :-\

rutabaga bob

Linear Power Booster.  A lot of people's earliest experience with guitar effects.
Life is just a series of obstacles preventing you from taking a nap...

"I can't resist a filter" - Kipper

Ruptor

#54
Here is the simulated circuit with your transistors but I think it might need a change of resistors to alter the gain which is too high I think.
http://s377.photobucket.com/user/Ruptor/media/FuzzFaceNoPots2N3904_zps60raduoi.png.html?sort=3&o=0

Electric Warrior

Hfe between 100 and 300 sounds more like they could have too little gain, but we don't know what his transistors read.
But before he can start worrying about that he needs to find the bug that's causing those weird readings.

Fndr8875

did u use the same 3904 in the LBP1? You board looks so fresh n so clean, i think you posted voltages on first page, illl look was curious what the 2nd collector was at, i have a clear breadboard just like that and used the same small bear tutortial and it worked but something was weird bc i used the same transistors he used and voltage was way off, so i redid it with the trim pot and at 4.5 volts it sounded like junk. but at like 2v it sounded like ud expect a FF to work. all your parts look new, long leads, bb looks new , did u measure yout pots on 1 and 3 to make sure they had good connectivity w wires, the 1 and 2 to make sureyou get smooth taper. ive had prob w pots in the past where itll jump way outta range then back in then to ground etc when i measure taper, but just measuring 1 to 3 gives me full value. so i always test both now. all i can think of...


The pots can cause no output if lug 2 of 500k pot doest have a good solder joint, trust me it took me a while to figureout why NOTHING i built worked, then id started measing pots before a build and seeing hmm why is multmeter not responding or jumping all over place. his soldering looks clean but something has to be wrong

bonzoboi

@Fndr8875 I feel encouraged to have someone on here who's done this project as well! And yes, I did used the same 2N3904 transistors on the LBP1.

I'm going to give this Fuzz Face another stab today, and give some careful attention to my pots and their solder joints.
I'm asking because I'm a beginner, but what is the best way to test my pots for good solder joints? Should I test them for continuity on the board, or test them for voltage when the battery is hooked up?

bonzoboi

#58
Here is an updated list of my voltages (the bottom/top/left/right leg indications are a reference to their positioning on my breadboard):

Voltage at the circuit board end of the red battery lead = 9.55 V
Voltage at the circuit board end of the black battery lead = 0.00 V

33K R
BottomLeg = 9.55 V
TopLeg = 3.38 V

100K R
LeftLeg = 2.78 V
RightLeg = 0.64 V

8.2K R
LeftLeg = 4.00 V
RightLeg = 9.33 V

330 R
Leg1 = 9.55 V
Leg2 = 9.34 V

0.01 mF C
LeftLeg = 9.33 V
Right Leg = 0.00 V

2.2 mF C = 2.78 V
PositiveLeg = 2.66 V
NegativeLeg = 0.00 V

22 mF C
PositiveLeg = 0.64 V
NegativeLeg = 0.00 V

Q1 T
C = 3.38 V
B = 2.78 V
E = 0.00 V

Q2 T
C = 4.00 V
B = 3.38 V
E =  0.64 V

500K P
CCW = 0.00 V
W = 0.00 V
CW = 0.00 V

1K P
CCW = 0.00 V
W = 0.64 V
CW = 0.64 V

I resoldered my pots, and made sure the connections were good across every component on the board with the multimeter. I also want to note again that the biggest issue I am having with this circuit/breadboard is that no signal at all is passed to the amp when it is plugged in, unless I touched the output jack with my hand, after which a loud buzzing comes from the amp. I'm still concerned that there is a grounding issue, but I don't know where it could be.

bonzoboi

#59
Wow, well, I think I found a big issue, and this is the part where I will probably look a little bit dumb.
I was under the assumption that I had ordered 2N3904 NPN transistors, and had been claiming that that is what I as using the whole time. However, I finally looked at the tiny inscription on the transistor and found that it was a 2N3906 PNP transistor. So, whoops! My apologies to anyone's time that I wasted by claiming I had different transistors. I'm going to look into obtaining some different transistors now to hopefully solve my problem.