switch issue? this is a new one for me...

pikingrin

what is this?
I'm still more or less a rookie when it comes to electronics; learned my fair share about the components but ran into a potential weird issue with a switch last night. Finished a WayHuge Red Llama OD clone, had to get it just because of the name, and it was an easy build. Very easy. 9 resistors, a single 4041 diode, a 12-pin IC and 2 pots to wire in (outside of the footswitch). This being my 11th or 12th build, I was confident until I got no signal when I turned the pedal on.

Doing my troubleshooting, I get continuity from beginning to end on the PCB and I get continuity from tip to tip from the input to output jack when in the off position. When on, continuity is cut and I can only trace it to the foot switch as everything else has checked out.
IMG_2715.JPG
So in the "off" position, I get continuity in all lugs EXCEPT 8 and 9. In the "on" position, continuity through all EXCEPT 1, 2, 6 and 9 - 9 being the output which is routed to the middle lug on a pot and then into the board through an outside lug.

When I crank both controls to the max, I get a static hiss output but zero throughput from the guitar. Curious if this is a bad switch as I've exhausted all other avenues of testing. Any ideas??
 
Hey,
I'm not sure I understand your continuity descriptions.
In one position you should have continuity between 4+1,5+2,6+3...(obviously 4/1/5/2 are bridged but never mind)
In the other position you should have continuity between 7+4,8+5,9+6.

If you ever have continuity between 2+3, for example, your switch is 90 degrees out.
 
Wow, thanks. I thought I had a clear understanding of these 3p2t switches but I guess not. FWIW, all of my continuity checks were done from the tip of the plug in the input jack since that goes directly to the switch. Not sure if that helps it make any more sense though...

Edit - just checked continuity through the switch the proper way and it checks out fine. Thanks, Steen!

Also, just in case, here's the wiring diagram for the pedal. Not sure if it will make a difference...
Screen Shot 2016-02-29 at 10.15.02 PM.png

Back to the troubleshooting. :o
 
Ah yes, OK, that makes more sense. Still, though..test the switch's basic functionality to prove correct orientation.
Does the LED even come on?

It's three switches in a row, each of which can go here or there.

IDK, if you imagine the middle row of pins (4/5/6) have stems coming up from them.
Those stems can fall up or down, as per your picture, bridging to 1/2/3 or 7/8/9. Make sense?
 
Re-reading your continuity descriptions now, yeah...that's not good.

In the off position your input tip should be continuous with 7,4 + 3, 3 being irrelevant in this position.
In the on position input tip should be continuous with 7,3+6...6 being the final output either way.

If you were to lift green from the board, blue from the pot, and tied their ends together, (removing the pedal from the loop) the switch should function as an on/on just passing dry guitar straight through. Maybe that's useful for testing?

Conversely you could lift yellow/green from the switch and tie them together,
then lift orange/blue from the switch and tie them together.
That removes the switch from the loop and has the pedal permanently on. Again, maybe a useful test or troubleshoot.


Also, measure for 9v at the pos and neg points on the board.
It's easy to wire those battery bypass power jacks wrong.
 
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