rookie issue... circuit works when touching resistor?

[jebop]

Hi all, I'm building a Voodoo Lab OD (schematic here: https://www.diystompboxes.com/smfforum/index.php?topic=118497.msg1103381#msg1103381), but it only seems to work when I am physically touching certain parts as well as my guitar strings. From my research, a decoupling capacitor will solve this...? I have the power section of the OD built on my breadboard too, which has decoupling caps, so I'm not really sure what the issue is. Thoughts?

[Marcos - Munky]

First of all, late welcome.

On your issue, something Is conducting when you're touching some parts of the circuit, and it doesn't conduct when you're not touching it. It seems to be cold solder joint issues.

Could You post a few pics?

[jebop]

First of all, late welcome.

Thanks!

It seems to be cold solder joint issues.

This is actually on a breadboard, so there aren't any solder issues (yet!). As far as conductivity goes, do you think the problem could be with thin leads on some parts?

[antonis]

IMHO, there is loose (or not at all) ground connection..

Some photos would help a lot..

[r080]

As far as conductivity goes, do you think the problem could be with thin leads on some parts?

While that can cause problems (which you can improve by tightening the breadboard socket from the bottom), as Antonis says, it seems like a ground issue based on the statement that you have to touch your strings as well.

Do you have your input and output jack rings tied to ground on the board?

[jebop]

Here are some pictures...

https://postimg.cc/gallery/pLn7Z47

The first is an overview of my board (jacks are mounted on the piece of metal)

The second shows the two resistors that have the magic touch

The third (blurry, sorry) shows the "power section" where I have +V going in and then going to the rest of the board.

I can send more with labels if anybody needs more clarification 

[r080]

I took a look a couple days ago, but forgot to reply. There were a few wires that appeared to be touching that maybe shouldn't be, but I don't think that should cause the issue. Nothing about those two resistors looked strange to me right away.

I noticed you did not solder your ground wires to the jacks. You might consider doing that, even with just a little bit.