want to build a "one-at-a-time" loop switcher....

[M.T.G.]

My bad for the horribly amateur-sounding title, I know there's a word for that...

Anyways, I want to build a box that has three footswitches, an input, three loops (send & return jacks), and an output. It's for my dirt pedals. I don't like having to press two pedals to change my sound once, so here's how I want it to operate:

Let's assume the pedal starts out in bypass mode (no loops engaged). I press footswitch #1, and my signal is routed through the first set of send/return jacks. I press switch #2, and my signal is then moved to the second loop (the first loop is bypassed and the second loop is engaged at the same time). I press switch #2 again, and my signal is now routed straight through the pedal, and through none of the three loops.

I think you probably get the idea already. I'm looking for a switching system that only allows one loop to be active at any given time. Pressing the active loop bypasses the entire pedal. Any suggestions?

[mikebike]

have you checked out beavis audio? he has alot of cool stuff like this.

you might have to do a relay system. or like a cmos thingy

[littlewing]

here's one possible option: (see attached schematic)

use a 4017 decade counter to switch through the loops. the pushbutton sends +V to the clock input to advance the counter. outputs 1-4 go to the control pins ("A") on a 4016 CMOS switch. on switches 1-3, the output terminals ("B" & "C") go to send and return jacks. the output terminals on switch 4 are shorted for bypass. of course you could put the bypass as the first switch, or whichever order you want. in jack is connected to all the send jacks and out jack is connected to all the return jacks.
output 5 from the 4017 goes to the reset pin on the same ic to loop back to output 1.

i'm sure the circuit will need some tweaking. i'm a little concerned about having the in and out jacks connected to all the loop jacks, as this may load your signal even when it's bypassed. you could probably use another 4016 to switch the in and out jacks to connect only to the loop that's selected, but i didn't feel like drawing that out.

p.s. don't mind those weird labels on the jacks and switch on the schematic, they were the only pushbutton and jacks that i could find in eagle light.

perhaps someone with a little more experience can verify this, but it should at least serve as a starting point.

hope that helps!
vito

[littlewing]

i just realized that having the in and out jacks connected to all the send and return jacks will send and receive to/from all of them. that was dumb. hopefully something on the schematic will help you at least.

vito

[littlewing]

ok, let's try this one more time.

this time the schematic includes two 4016. one switches the in jack and one switches the out jack. so when the 4017 is at the first position, a pulse is sent to both 4016 and the switch is closed, connecting the in jack to send 1 and the out jack to return 1, and so on.

this seems to make more sense to me. anybody?

-vito