Need help building 3 channel pedal. Possibly using relays?

[mitch95]

Hi everyone! Quick background cause its my first post, I registered on here today because it looks like the BYOC forums are no more. I'm 18, I've built several pedals, both from kits and original designs, and I've been playing guitar for 11 years.

Anyway, I'm working on a new project, and I need some help. Its essentially a 3 channel pedal, so there will be 3 separate effect PCB's inside one box. I want to have 3 stomp switches, and when you step on one, it will switch to the effect tied to that switch while simultaneously turning off the other 2. (Only one effect can be turned on at once). I worked this through in my head and on paper, and it seems impossible to do with standard 3DPT switches. So I was wondering, is it possible with relays? I haven't worked with relays before, so if anyone could explain to me how I might go about this, that would be extremely helpful. Also, are there any potential problems I could run into if the outputs of the 3 effects PCB's are all soldered to the same output jack? Would I need to modify any circuitry so they don't have unintended electronic interactions?

Thanks, looking forward to being a part of this forum!   

[psychedelicfish]

Relays would be more trouble than they're worth. You might want to consider doing something like this

[Seljer]

If you need 1 out 3, 1 at a time, and 1 always on, you can do it electromechanically with latching relays, momentary footswitches and a bunch of diodes to route the switching signals.

It gets tricky when you add the switching logic necessary for bypassing (unless you add a 4th switch for bypass).
The simplest solution really is to take a 8 pin PIC microcontroller and let it handle all the switching logic and then switch the audio with regular relays (or the CD4053 that was linked by psychedelicfish there).

[davent]

Hi everyone! Quick background cause its my first post, I registered on here today because it looks like the BYOC forums are no more. I'm 18, I've built several pedals, both from kits and original designs, and I've been playing guitar for 11 years.


Thanks, looking forward to being a part of this forum!   

Works ok for me.

http://byocelectronics.com/board/

[mitch95]

Can you recommend a particular latching relay?

[jubal81]

TH_Custom makes just the the think you're looking for. Called the "Ultimate switch strip"

http://diy.thcustom.com/the-ultimate-switch-v1-0-diy/

[davent]

If you google Mictesters ultra low current relay you should get a thread on another forum that has a cool little circuit as well as the part number for the needed latching relay.

dave

[PRR]

> looks like the BYOC forums are no more

http://byocelectronics.com/board/  -- ??

There is a different URL which seems to have lapsed recently.

[tranceracer]

4049 Flip-flop relay ckts are pretty easy to build.  You can build two relay latching ckts from one 4049 16 pin (6) flip-flops.

Here's a couple quick vids of the ones I build.
http://s215.photobucket.com/user/tr-stompboxes/media/MVI_0007.mp4.html?sort=3&o=44
http://s215.photobucket.com/user/tr-stompboxes/media/MVI_0003.mp4.html

My quad relay switcher:


Tactle switch assembly.  There's pre built N-O switches for sale at small bear.


Someone on the forum has a really nice micro processor switch that uses less components and is a little more elegant than mine!  (;
Cant remember who it was tho...

[screamersusa]

I'm using plain old 3pdt switches.
For a three channel say clean, rock and hell I'd do:
Button 1, clean and button 2 feed
Button 2, rock and hell.
I've been using 2 resistors on the leds so they will dim on the unused bank so
the active channel is bright and the other side is not.
My 5 channel is wired as follows with 4 buttons:
Button 1 is bank 1, clean (Vx100)or rock (marshall),
button 2 selects bank 1 or 2
button 3 is rock (mesa/marshall), and Engl Savage
Button 4 is a lead override that doesn't care what is selected on bank 1 or 2.
I'm switching both input and output to each device, shorting the unused inputs to ground..

I'd love to see a simple digital one.