Messages

When I started to explore the world of building guitar pedals I knew I had to learn a lot, and I'm sure that asking pros on this site and practicing with the right advices are great ways to improve my technique.

Thank you nzCdog, for your precious time. As soon as possible I'll give you news about my challenge 

This is the rear:
http://imageshack.us/photo/my-images/850/img0924v.jpg/

and this is a close shot in order to focus on some joints that look connected in the previous image, but they're not:
http://imageshack.us/photo/my-images/853/madbc.jpg/

For any other pic just tell me!

Writing about the trimpot made me think about a thing.
Just to be certain.. another thing I did differently fron the project was to invert the pinout of two of the four pots.

I mean, in order to create a cool W-shape layout of the knobs, and having four pcb-mount pot, two of them must be rotate clockwise, and the other two counterclockwise. I actually did it (and did not tell you) knowing that a pot is a resistor with a sliding contact that gives an adjustable value. So I thought that inverting pin 1 and 3 would have just caused an opposite rotation.

Is this right?

Here they are.
The yellow wires are short extensions I did for the pot's pins.
As you can see the trimpot is mounted on the opposite side because the one I got has the correct value but wrong size. I just soldered it after bending the pins.

http://imageshack.us/photo/my-images/339/img0916kd.jpg/
http://imageshack.us/photo/my-images/339/img091823.jpg/
http://imageshack.us/photo/my-images/24/img0917zu.jpg/
http://imageshack.us/photo/my-images/571/img0921uu.jpg/

[beginning]

(Thank you wstimson! I've never studied electronics, I've just followed instructions so I didn't know that )

Well...in my local store I couldn't find ANY of the active components of the project, so I'm going to buy again on banzaimusic.com in order to replace all the ICs and transistors.

nzCdog, I'm thinking about when you gave me your VR and noticed that mine were all double value, so that one or more components at the beginning of the circuit could be broken.

For example, according to your VR, my Q1 (that I've never replaced) give me double voltage at the source pin. And it is actually at the beginning of the circuit.

This affects all the other components, right? So is a good idea to replace these active components?

[pin 6 - 1.50]

Guys, I've just finished to test once again my pcb.

First of all, I started to check again all the components.

- All the diodes and the ICs are in the correct orientation, and all the electrolytic capacitors as well. Good.
- I checked my old VR, being sure to collects numbers according to the correct pinout (as suggest by nzCdog) and yes, I did it right.
- In my last post, as I told you, I replaced Q2, Q3 but I forgot to tell that I replaced IC3 and IC4 too, with new ones. Since then, my VR have changed a little bit: I'll write them all again putting the changes in evidence:

IC1  TL072

pin 1 - 8.32
pin 2 - 8.33
pin 3 - 4.16
pin 4 - 0.00
pin 5 - 4.99
pin 6 - 8.34
pin 7 - 8.40
pin 8 - 9.05

IC2  LM324  

pin 1 - 7.77
pin 2 - 7.40
pin 3 - 7.82
pin 4 - 9.05
pin 5 - 7.83
pin 6 - 7.33
pin 7 - 7.77
pin 8 - 7.77
pin 9 - 7.40
pin 10 - 8.09
pin 11 - 0.00
pin 12 - 7.32
pin 13 - 8.10
pin 14 - 0.00

IC3 CD4013

pin 1 - 9.05
pin 2 - 0.00
pin 3 - 0.00
pin 4 - 0.00
pin 5 - 0.00
pin 6 - 1.50 (maybe I signed the wrong number in this one - my multimeter is digital, so I may have read 7 instead of 1)
pin 7 - 0.00
pin 8 - 0.00
pin 9 - 0.00
pin 10 - 0.00
pin 11 - 0.00
pin 12 - 0.00
pin 13 - 9.05
pin 14 - 9.05

IC4  CD4013

pin 1 - 0
pin 2 - 9
pin 3 - 9
pin 4 - 0
pin 5 - 9
pin 6 - 0
pin 7 - 0
pin 8 - 0
pin 9 - 0
pin 10 - 0
pin 11 - 0
pin 12 - 0
pin 13 - 9
pin 14 - 9

IC5 TL074

pin 1 - 7.80
pin 2 - 7.80
pin 3 - 7.88
pin 4 - 9
pin 5 - 4.7
pin 6 - 7.80
pin 7 - 7.90
pin 8 - 8
pin 9 - 8.15
pin 10 - 7.90
pin 11 - 0
pin 12 - 4.75
pin 13 - 7.80
pin 14 - 7.80

IC6  TL074
pin 1 - 8.45
pin 2 - 8.28
pin 3 - 8.58
pin 4 - 9.05
pin 5 - 8.58
pin 6 - 8.42
pin 7 - 8.45
pin 8 - 8.45
pin 9 - 8.33
pin 10 - 8.52
pin 11 - 0.00
pin 12 - 8.52
pin 13 - 8.21
pin 14 - 8.39

Q1 J201

pin 1 - 9.05
pin 2 - 8.32
pin 3 - 4.28

Q2 2SK30

pin 1 - 7.80
pin 2 - 8.40
pin 3 - 7.80

Q3  2SK30

pin 1 - 7.80
pin 2 - 8.40
pin 3 - 7.80



So, I started to check even the only thing I was sure about: resistors. And here's the buzz:

I bought my components on www.banzaimusic.com, so they arrived packed in plastic bags, with labels, with data on each one. For this reason, it is way more easy to solder the resistors following the order of their values.
I mean, for example, I put down all the 1M resistor, then all the 47k, and so on. Following the order of the resistors of the project (R2 after R1, ....R46 after R45...) forces you to open more than a plastic bag, and that is more risky.

Of course, I did everything very slowly and double checking, I was sure I put the right components in the right places before soldering. But actually I didn't use my multimeter on each resistor to test if the guys of Banzai did their job right.


Anyway, few hours ago I was in my lab looking for an issue, so I did it: I used my digital multimeter and test them.
Well... Some values are perfectly right...but some others....!
Here's what looks wrong to me:

R3 - 6.9k instead of 10k
R11 - 800k instead of 1M
R12 - 7.8k instead of 10k
R13 - 7.8k instead of 10k
R14 - 7.8k instead of 10k
R17 - 48k instead of 220k
R19 - 89.3k instead of 100k
R21 - 33.7k instead of 47k
R23 - 55.5k instead of 100k
R34 - 6.7k instead of 10k
R35 - 7.43 instead of 12k
R46 - 42k instead of 120k
R47 - 90k instead of 1M
R48 - 87k instead of 220K
R49 - 40k instead of 56k
R54 - 47k instead of 1M
R55 - 70k instead of 160k

Ok, you may say that these are too much. That I was drunk when I soldered my pcb. That I'm blind.

I just couldn't believe I wrong so many values. So I checked the stripes on each one: they ARE RIGHT.
So what the hell happened?! Are they burnt or something? Is my multimeter broken? It's me, that I'm not able to use it in the correct way? If it's me, why all the other values are perfectly right?

In any case, thank you all for your answers, I appreciate that.

Alle

[it worked!!]

I tried to replace Q2 and Q3 with new ones. Then I connected the pcb to the input and output jacks and plugged my guitar in: it worked!!
BUT when I turned the pedal off and on again... Once again, a noisy distorted sound.

Any idea??

[Project Name:]

Project Name: Lowrider

General description of the problem:
After I finished soldering all the parts on the pcb, I tested it and it worked great. So I boxed it.
Everything was fine, I plugged my guitar in and it sounded just as it should.

The same day, after a couple of hours, I turn it on again and I heard just some scratches, and some weird sounds, and no guitar signal at all.



Steps that I have taken to try to resolve the issue

I double checked my wiring, my part values, my part orientation, my soldering job.


When the pedal is turned off, the true bypass works perfectly.

After I tried to open the box in order to find out if there were some bad connection, I didn't notice anything strange, any part unconnected, or any weak connection. Then I tried again to play something, and this time I could actually hear my guitar signal, but distorted and with no octave.
The signal came and went, sometimes I heard no sound at all, sometimes a distorted sound.

Then I noticed that one of the pin of the 3PDT switch moved a very bit if you touched it. So I replaced the 3PDT with a new one. Now I don't hear no sound anymore, but it is still distorted and with no octave.

List any substitutions I used for parts/values

I left C12 off, and used a 1n capacitor instead of 10n for C10, as suggested by the .pdf project. The upper octave sounded a bit fuzzy, as the project said it would, but when the pot of the upper octave was all turned down the sound was perfectly clean, so everything was ok.

Here are my DC measurements on all the IC and Transistor pins (black lead of the Mulitmeter to ground, reliable power to the circuit)


Positive lead at jack/battery
9.04

9V in at board
9.04

Ground in at board
0.00

IC1  TL072

pin 1 - 8.32
pin 2 - 8.33
pin 3 - 4.16
pin 4 - 0.00
pin 5 - 4.99
pin 6 - 8.34
pin 7 - 8.40
pin 8 - 9.05

IC2  LM324  

pin 1 - 7.77
pin 2 - 7.40
pin 3 - 7.82
pin 4 - 9.05
pin 5 - 7.83
pin 6 - 7.33
pin 7 - 7.77
pin 8 - 7.77
pin 9 - 7.40
pin 10 - 8.09
pin 11 - 0.00
pin 12 - 7.32
pin 13 - 8.10
pin 14 - 0.00

IC3 CD4013

pin 1 - 9.05
pin 2 - 0.00
pin 3 - 0.00
pin 4 - 0.00
pin 5 - 0.00
pin 6 - 7.50
pin 7 - 0.00
pin 8 - 0.00
pin 9 - 0.00
pin 10 - 0.00
pin 11 - 0.00
pin 12 - 0.00
pin 13 - 9.05
pin 14 - 9.05

IC4  CD4013

pin 1 - 9.05
pin 2 - 0.00
pin 3 - 0.00
pin 4 - 0.00
pin 5 - 0.00
pin 6 - 0.00
pin 7 - 0.00
pin 8 - 0.00
pin 9 - 0.00
pin 10 - 0.00
pin 11 - 0.00
pin 12 - 0.00
pin 13 - 9.05
pin 14 - 9.05

IC5 TL074

pin 1 - 8.45
pin 2 - 8.28
pin 3 - 7.88
pin 4 - 9.05
pin 5 - 5.07
pin 6 - 8.44
pin 7 - 8.45
pin 8 - 8.45
pin 9 - 8.35
pin 10 - 8.25
pin 11 - 0.00
pin 12 - 5.04
pin 13 - 8.45
pin 14 - 8.45

IC6  TL074
pin 1 - 8.45
pin 2 - 8.28
pin 3 - 8.58
pin 4 - 9.05
pin 5 - 8.58
pin 6 - 8.42
pin 7 - 8.45
pin 8 - 8.45
pin 9 - 8.33
pin 10 - 8.52
pin 11 - 0.00
pin 12 - 8.52
pin 13 - 8.21
pin 14 - 8.39

Q1 J201

pin 1 - 9.05
pin 2 - 8.32
pin 3 - 4.28

Q2 2SK30

pin 1 - 8.30
pin 2 - 8.64
pin 3 - 3.00

Q3  2SK30

pin 1 - 7.90
pin 2 - 8.57
pin 3 - 0.00



IC3 and IC4 measurements look a bit...burnt, don't they?


Thanks for your time,

Alle, Sassuolo, ITALY

I replaced the 3PDT with a new one.
Now, when the pedal is turned on, I can actually hear the sound of my guitar, but it's dirty, distorted and there's no octave.

How do you test if there are some ICs or some transistor that need to be replaced?

[moves]

I noticed that one of the pin of the 3PDT switch (the one that brings the input wire to the pcb) moves a bit if you touch it!
I'm afraid I've blown it up while I was soldering...

As soon as possible I'll try to replace the whole 3PDT with a new one, then I'll let you know if it will work again.

Hello to everyone!
I found myself stuck in a very frustrating situation that I'm not able to explain!

this morning I finished to give life to my own Lowrider: everything was fine, I plugged my guitar in and it sounded great!
I left C12 off, and used a 1n capacitor instead of 10n for C10, as suggested by the .pdf project, so maybe that's why the upper octave sounded a bit fuzzy, but when the pot of the upper octave was all turned down the sound was perfectly clean, so everything was ok.
Well, I enjoyed playing my stompbox for several minutes and I was very happy about how it sounded.

This afternoon, when I returned home, I turn it on again and...there was no sound at all!

When the pedal is turned off, the true bypass works perfectly. But when i turned it on, I can hear just some scratches, and some weird sounds, and no guitar signal at all. After I tried to open the box in order to find out if there were some bad connection, I didn't notice anything strange, any part unconnected, or any weak connection. Then I tried again to play something, and this time I could hear my guitar signal distorted and with no octave.

I built a couple of stompboxes before, just following the instruction, and they all worked great. But I have to say that I'm not an expert in electrical engineering and I have no idea about what I can do.

Does anybody have any idea of what the problem could be?

Thanks for your time,

Alle, Sassuolo, ITALY