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Hi again.
Lately my Germanium Fuzz (first build ever) started to behave very oddly. Low volume, cracking noise, the whole shabam. Bypass works fine.

I opened it up. Hell, my soldering was really something special . First pedal, remember
Anyway. I reflowed, checked some things. Couldn't find anything.
I got my signal tester and started probing.

Remember, I still have a LOT to learn, but i couldn't really understand the following:
With my amp cable in the signal tester (and grounded):
- i probed the IN on the PCB: weak and crackling signal with pedal ON, no sound with pedal OFF
- so I probed the tip of the IN jack (coming from my BOSS looper, so I don't have to play guitar all the time ): with the pedal OFF, the signal was loud and clear. With the pedal ON, the signal became weak.
That does seem odd to me, or am I proving that I really could use some more lessons in electronics?

Greetings
tom

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Somehow I remembered that there was an extensive troubleshooting section in the instructions of this pedal, so I tested it (fuzzinstructionsrev2.pdf => i can't attach this)

This is what I found out:
- not the transistors i think, because the S9013 had the same problem
- didn't check the power or bypass problem, because i have power and the pedal works in bypass
- i checked continuity outside the pcb, everything fine
- i checked the audio path, NOT as it should be:
* clean tone from 1 till 5
* fuzz at 6 (but only when fuzz knob is full CCW, with the knob fully CW there's NO sound at 6)
* fuzz sound stays the same until 14, but that seems logic depending on the setting of the trimpot
* after that no change

- i checked the voltage at the Q2collector bias. something i didn't understand here:
* with black probe on any sleeve and red probe at 1: i get the voltage i should (between 3 and 6 depending on the trimpot)
* but with red probe on 2 i get 9.15V with trimpot fully CCW and 8.30V with trimpot fully CW

So far my understanding of what's happening

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Post some clear, well focused pictures of the front and back of the board. Someone should be able to help you solve the problem.

Here they are.
Sorry about the soldering. It was my first pedal
I reflowed every joint real quick. Remember I did the audioprobe test (as mentioned above).
Every picture is either around 200kb or more then 1 Mb (which I can't attach). I hope they're clear enough (to see the lousy soldering )

Thanks for helping me out!

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How do your jacks look? If a pedal is OK and then starts having problems after several years of use, it's usually something to do with the jacks and not a component on the PCB. I can't tell you how many times something like this comes up and it ends up being a cold solder joint on the jack that finally broke loose.

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Please do not PM me. email is prefered. keith@buildyourownclone.com

Thanks Keith
I'll double check, but bypass is ok and my audiosignal passes through the pedal.
Isn't it weird that my audio signal starts to "fuzz" at 6 (as described above?).
I followed these instructions:
3. Test the audio signal path.
Do this using a Signal Test Probe. If the audio signal stops at BLUE8, then you likely have a problem with Q1. If it stops at Blue11, you likely have a problem at Q2. You should notice a large volume boost at BLUE9 and deminished volume at BLUE 6 - 8 when compared to BLUE1 - 5. You should notice “fuzz” at BLUE12 and all points there after.
And I noticed quite different things.

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Check your foot switch wiring as well. The wires for bypass may be fine, but the wires for send/return might not.

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...or the internal connections for the "engaged" position within the footswitch may be compromised. As an electro-mechanical component, the footswitch is probably more prone to failure over time/usage than anything else in the pedal.

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Ok. I'm learning a lot here

I checked continuity in the footswitchbefore posting my problem.
I asume that if the continuity is as it should be, theswitch can't be the problem?
It either "passes" or it doesn't. Or is this incorrect?

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Generally, that's the case. But what you've described sounds like an intermittent contact problem, and it's possible that such a condition could be present inside the footswitch. Most commonly, these problems are caused by solder joint issues, but if you've gone through the pedal thoroughly and re-flowed all the solder joints, then it makes sense to look at other possibilities. (And if you didn't re-flow every joint in the pedal, I'd strongly recommend that you do so.) Try wiggling the top of the footswitch and see if it makes the problem come and go. The other electro-mechanical parts to check out are the pots; try turning each of those back and forth and see how the pedal output responds.

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“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Ok
This Fuzz is driving me loco.
Been building a lot of pedals since, so I took this "problem pedal" back on my bench today.
Re-checked the whole troubleshooting guide in the instructions.
Re-read every post in this thread.
Re-flowed everything just for the heck of it

No "errors" in the Troubleshooting guide until the section 3 with the audiopath.
Perfect clean signal in 1 to 5.
Then on the other side if this 100K resistor: stuttering, phasing/flanging, fuzzy sound.

Checked the resistor: was 110K. Changed it for a new one anyway.
No difference.

Then I checked the B1K fuzz pot. Because there wasn't (a lot of) stuttering fully CCW. Only when turned CW.
Found a problem here: The pot was defective. Luckily I had another one that I put in.

Now, the phasing stuttering is only fully CW.

Maybe this is how it should be, but STILL:
1/ audio path in 6 should be slightly less volume then in 5, not louder and fuzzier (fuzz should only start at 12)
2/ When checking the Q2 collector bias: No way I can get less then 6,8 V however I turn the trimpot.

It's driving me crazy, for such a small PCB whit such a low component count, i feel like like starting it all over again with new components, if it wasn't for the price tag.

Any suggestions?

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If you can't get less than 6.8V, there is a problem with the transistors.

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*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

I tested the PCB with the replacement transistors (that were included) a while ago and it was the same problem.
Therefore i concluded the Ge transisors where fine.

I'll test again tomorrow.

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