First Pedal, not sure where I went wrong

Started by Mastrofski, January 05, 2012, 12:41:46 AM

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Mastrofski

So I just started building my first pedal the other day, I went and finished it today, and lo and behold it won't do anything. I was hoping that some people here could share some insight as to what could've gone wrong. Also, because this is my first pedal(and subsequently my first debugging post), I'll do my best to include all the information I can but I'd be more than glad to clarify if I need to.

I used the fluorescent fuzz from : http://makezine.com/images/19/LB4PROJECTS.JPG

My initial idea was to use all parts from CFLs like intended but I ended up just getting parts myself.

I drew out the schematic by hand to get a feel for drawing them, but I labelled the parts so I could refer to them easier: http://img269.imageshack.us/img269/1640/fluorescentfuzzschemati.jpg

Here's where I placed everything: http://imageshack.us/f/403/fluorescentfuzzcompside.jpg/
And the backside: http://img80.imageshack.us/img80/2635/photodjh.jpg
The wires going to the bottom are for the ground

And just so you guys can get an idea of where everything is:
9V :  Positive A3
        Neg: A5
C2: I1 - M1
C3:  T3-U3
Output:    Hot W3
               Ground X5
R2: I3-M3
R1: D6-D10
R3: R6-R10
Q2: B P14
      C R13
      E R15
Q1: B E19
      C G16
      E G19
R4: M21-Q21
R5: V21-U23
C1: D23-D25
C4: Y23-Y26
Input:    Hot A25
            Ground C30

For the transistors I used 2 2N4401 NPN's

When I hooked it up, I'm not getting any sound from the amp UNLESS the battery is unplugged and I press my thumb up against the battery jack


Where I think something may have gone wrong(and again this is my first pedal so I'm kind of just guessing):
R5 - I used an resistor out of an old record player and I don't think age will kill these things but I figured I'd mention it
C4 - I used a tantalum capacitor and while I'm fairly certain I hooked it up right, I was a little confused when putting it in as which side should be pointing where
Jacks - I'm not 100% certain I wired them up correctly as most guides I saw how to do it were showing how to wire it up with a switch and I did not include a switch with this
The transistors I'm wondering how I would go about checking them to see if I had left the iron on for too long
C3 - I actually salvaged this from a CD player, and I think caps go bad swith age but this CD player is only like 10 years old and I'm not sure they're lifespan

Some things that are throwing me off:
When I put the battery in and test the positive and negative leads I'm getting a solid 9Volts, but no continuity, so that's confusing to me
I tested the resistors, both R5 and R4 are testing at 1.687 KOhms

I guess how would I go about fixing this and what would you guys be looking for?

lopsided

hi,
I don't have time right now to study this, but just a few tips.

When debugging the best information you can give are the voltage readings of all active components, in this case the two transistors, all three lugs.
For more tips on how to make your post as helper friendly as possible check here: http://www.diystompboxes.com/smfforum/index.php?topic=29816.0
For a perf layout the general rule is to use as little wire jumpers as possible, and use just the leads of the components. The more unnecessary paths you make, the more possibility for a mistake.
Also a good idea is to use sockets for transistors, this way you won't hurt them while soldering and you can easily switch them if necessary.

One more suggestion, should this go over you're had, consider going back and trying the beginner booster project at this forum, which leads you through the whole process step by step. 
J.

Perkla

I really think u should buy a beginners kit or at least build something that have alot of information about it here on the internet so u get a touch about what its all about when building pedals and what components are used etc etc, with a beginners kit u will get all the parts u need and u can study them and learn how they work.. including the 3PDT footswitch. I started of by building a simple Booster kit...with all parts included..  :icon_biggrin:

deadastronaut

breadboard it.......then you can tweak it, test it, see if you like it........ ;)
https://www.youtube.com/user/100roberthenry
https://deadastronaut.wixsite.com/effects

chasm reverb/tremshifter/faze filter/abductor II delay/timestream reverb/dreamtime delay/skinwalker hi gain dist/black triangle OD/ nano drums/space patrol fuzz//

J0K3RX

Quote from: deadastronaut on January 05, 2012, 09:12:20 AM
breadboard it.......then you can tweak it, test it, see if you like it........ ;)

+1 on that! Also, with a breadboard you don't have to plug in your soldering iron ;)
Doesn't matter what you did to get it... If it sounds good, then it is good!

Mastrofski

Well it's a little too late for me to breadboard it considering I already have all the connections soldered in.

Also, I just realized I had grounded R4 out for some reason so I cut that and now it still won't work but when I plug in the cord to the guitar I'm getting a little bit of a noise from the amp and nothing after that

alparent

#6
Sorry, not much help for now.

Do you have a tester? Pictures of the input and output jacks could help.

deadastronaut

@mastrofski, i had a minute so i knocked this up for ya!... ;)

this is how it should be from that schematic you posted ok...hope it helps..






https://www.youtube.com/user/100roberthenry
https://deadastronaut.wixsite.com/effects

chasm reverb/tremshifter/faze filter/abductor II delay/timestream reverb/dreamtime delay/skinwalker hi gain dist/black triangle OD/ nano drums/space patrol fuzz//

PRR

> I used the fluorescent fuzz from

Yet Another Fuzzy Face.

Collector of Q2 (where the 6K8 goes) must be more than 1V but less than 8V. Odds are it is stuck at zero, at +9V, or you have a problem with the signal in/out wiring.
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petemoore

  I was under the impression those bulbs are a hazmat item' when broken.
Convention creates following, following creates convention.

DavenPaget

Quote from: petemoore on January 06, 2012, 06:01:30 AM
  I was under the impression those bulbs are a hazmat item' when broken.
Probably not , i have never found any mercury in the CFL's i broke ( they are burnt out ) .
Hiatus

mrmoo1337

you don't see it because they contain mercury vapor!   Do not break the bulb!


DavenPaget

Quote from: mrmoo1337 on January 06, 2012, 12:48:49 PM
you don't see it because they contain mercury vapor!   Do not break the bulb!


... I did :icon_mrgreen:
As in obviously i can't see it but the vapor turned into MERCURY !
Hiatus