Author Topic: 3PDT Question  (Read 3872 times)


3PDT Question
« on: March 12, 2005, 03:54:07 AM »
Hello all,
I've been lurking on this forum for quite a while now, but I just now got around to posting for the first time. I'm very new to stompbox building, and this site got me motivated enough to attempt my first solo build. I built the beginner project tonight, and it worked on the first try! Kudos to Aron for writing clear enough instructions that someone like myself (who just picked up a soldering iron for the first time) can make it work. Actually, saying that it works is a little bit of a misnomer. I cut to the chase and integrated a 3PDT into the pedal right away. I didn't have a 1k resistor, so I didn't wire the dead middle pin to 1k resistor to LED to sleeve. Now when I click the footswitch it's either active (boost working and sounding sweet BTW), or it's supposed to bypass, but no sound comes out. One thing that got me a little confused was the bottom 3 pins are labeled "varies with LED". Am I supposed to run any connections to/from them?  RIght now, I just have the setup:

Input | +9v (on circuit board) | Output
Stereo Input tip | Nothing | Mono Output tip
Nothing | Nothing | Nothing

Could someone be kind enough to tell me what I might be missing?

Thanks in advance.


3PDT Question
« Reply #1 on: March 12, 2005, 04:22:37 AM »
Connect the two OUTER "nothing" on the bottom to get a bypass.

See this:

and - reference the BLUE wire on the following picture:


3PDT Question
« Reply #2 on: March 12, 2005, 04:31:17 PM »
Thanks for the quick reply! I connected the other two pins on the bottom with a piece of wire, and bypass is working now. I ran the pin that's dead center to a wire to a 1k resistor to an LED to the sleeve on the stereo input. I ran a wire from the sleeve to ground on the circuit board. With the LED in place, the boost quit working; however, if I remove the LED and just run through the 1k resistor, it works fine. I've tried orienting the LED both directions since I know it's polarized, and neither direction works. I'm wondering if I'm missing something since you're diagram states that the bottom 3 pins "vary with LED"? Would you mind clarifying what that means exactly. Sorry for being such a newbie.


3PDT Question
« Reply #3 on: March 12, 2005, 04:35:33 PM »
Typically the flat side, and/or the shorter lead, is the ground of the LED.


3PDT Question
« Reply #4 on: March 12, 2005, 05:50:51 PM »
Thanks... it was a loose connection.


3PDT Question
« Reply #5 on: March 12, 2005, 09:52:27 PM »
I think the "varies with LED" statement is supposed to be referring to the resistor value - not the pins on the switch. I was confused by that when I first saw it too.
Congratulations on your successful build 8)