Anyone know electronics?

[HelpDeskHustler]

Ok so here's the deal. I have two identical negative wires and one positive. I have no idea what the voltage or current is, I know the voltage is less than 12V. I need to make a circuit as simply as possible that alternates current between the positive to one of the negative wires and the positive one to the other negative wire. Sort of like an electronic three way valve. The only restrictions on how fast are between .5Hz and 20Hz. I only care about it changing, I don't care if it's on one for longer than another, it just needs to change a certain number of times consistently. I cannot suck power from the line to run the device unless all the voltage will reach the end. My dad thinks there's a way to do it with just one well picked capacitor and a transistor, but I can't figure it out.

[Ace24]

I think you just need to stop trying to mod your rockband guitar.

[HelpDeskHustler]

I have a pump gun now, I can't mod that.

[Ace24]

Duckslide it.