D*A*M Forum

Yo,
I just built myself a little A/B switch with LED's and a power tap. I simply copied the one on the Fulltone site...

http://www.fulltone.com/PDfFiles/AB_switcher.pdf

Anyway, it works great unpowered (but this means no LED's), but as soon as I power it, it still works but it becomes quite noisey.

I'm no expert so it'd be great to get some advice on what might be going on here.

Thanks so much,
Xan :)

You do have the 2.2k resistors in there right?

Hey, in that pic it looks as if the jacks' tip connections are touching the resistor leads.
Check that.

Also, ¿What are you using to power that box?

cheers for the input, I checked the resistor leads and they aren't touching anything, it does look like they are in the picture but they are a decent distance higher than the 1/4" jack.
Someone over on TGP suggested that the cloth wire might be an issue, is this possible? It's the only stuff I had lying around and didn't really put much thought into using it!
And to power the box I'm using a T-Rex Fuel Tank Jr.
Cheers,
Xan :)

To rule out the PS you can connect a battery clip and check whether that solves the problem.
If not, I would reheat all connections - worst case scenario quickly rebuild. A lot of the time, that goes quicker

hmm, the test suggested is good but I don't think the PS is the culprit, because that Fueltank is a very good source.

smogfalls wrote:Someone over on TGP suggested that the cloth wire might be an issue, is this possible?

Hmmm, I don't think so, it would give you trouble even with the PS disconnected.

Try sticking a large electrolytic cap (100uF maybe) across the power jack.

SonicVI wrote:Try sticking a large electrolytic cap (100uF maybe) across the power jack.

That and a small plastic cap (0.1 - 0.33 [uF]).

well... a few days later and the problem now seems to have gone away. I took the advice on re-heating the joints and I totally re-did the one's around the resistors, and it seems to have fixed the problem.
Thanks so much for all the help, it's greatly appreciated. It's awesome to have a portal to knowledge sitting here in my bedroom!
Thanks again,
Xan :)