Acoustic 360 fuzz : voodoo issue when boxed

[eve-the-frog]

Hi,

Ok, I have to keep cool because this bug's gonna make me CRAZY !!!

This the layout of my build found on this thread http://guitar-fx-layouts.42897.x6.nabble.com/360-V-4-Bass-Fuzz-td8606.html#a8713



When Finshed I've tested it unboxed and all worked great. I boxed it and it didn't work : no sound at all, nothing. I unboxed it, re-wired it outside of the box and all work great. I boxed it again and it didn't work : no sound at all. I unboxed the board, checked each pot for a ground issue, changed the two output jack sockets, changed the the power socket and removed the transistor sockets to solder them directly on the board. Also checked the 3PDT switch. It worked perfectly well unboxed. And when I boxed it for the third time it didn't work. Same : no sound at all. Someting like a white noise when blend pot fully CCW.

AaaaaAaaaaaaAAaarrrrrrggggghhh ! I spent two days on this little piece of **** and it still didn't work !

Here is the guts of the beast.  Pretty messy wiring, but remember I've made it threee time !!



Did you experimented something similar ?

[PMowdes]

What's happening with the 9v supply? Looks like it's wired to the blend pot???? 🤔

[PMowdes]

Or is that the LED???

White noise in my experience in usuallyDC power leaking into the signal path

[eve-the-frog]

You're right : the big red wire is the LED.

What do you mean exactly by "DC power leaking into the signal path " ?
And why is it happening only when boxed ?

Another question : do you think it's normal to have 2,3KΩ between the red wire of the DC socket and the ground ?

[PMowdes]

Where is the 2k3?? Can't see it on the layout

[eve-the-frog]

Sorry, I probably don't tell it the right way (I'm french by the way).

When I measure the two wire of the DC socket (when the unit is disconnected from the power supply) I get this measure : 2,3KΩ.

I think there should be no resistance between these two wires... But not sure.

As I'm desperate I check stupid things :oD

[eve-the-frog]

I made it work ! :)

But I don't know how... :(


I found that when everything is boxed except the pots it works. I then tried to reinstall each pot individually and test the result : it works. I then reinstall the pots one by one and tried : it works to the point where all pots where boxed in place. And now it works.

It's cool that it works, but I'm a bit disapointed that I didn't understand what happened...

Anyway, thanks for your help PMowdes !

[PMowdes]

I wonder if one of the pots was shorting against the enclosure.

[Travis]

Could be an intermittent connection. You could try plugging it into your amp and wiggle/gently tug each wire around while the effect is switched on. If you hear a weird noise or the sound cuts out when you move a wire then check the solder joint and wire

[eve-the-frog]

I did all these tricks to find where something's grounding. But with no results...

Fortunately everything works fine now.

I know this not the pace to ask this question but in another build (Madbean Ping reverb) I wonder if I can replace the 1uF polarized electrolytic caps by 1uF non polarized film box caps ?