Dual Footswitch Wiring - Right LED Turns off When Other Is Turned On

[natron_mn]

I'm having some trouble with a King of Tone Clone. The pedal works perfectly fine, but there is a quirk. When I have the right side engaged, and then I engage the left side, the right LED turns off. However the right side is still active, it's just the LED that turns off.

Below are pictures of the pedal itself as well as the wiring diagram I followed. One note - I used two 4.7k resistors. Could this be it? Would an LED turn off if the resistance was too high (9.4k)?

[thermionix]

I'm confused about several things here.  You have a 4.7k going to each LED?  They don't combine in series to make 9.4k do they?  That footswitch diagram calls for 339 ohm CLRs?  That's an odd value, and much lower than any I've seen used for that purpose.  4.7k seems to be pretty standard for "regular" 5mm red LEDS.  The "high brightness" LEDS that I've used want more like 47k.

When I have the right side engaged, and then I engage the left side, the right LED turns off. However the right side is still active, it's just the LED that turns off.

Is the right side supposed to remain active?  I think that's what you mean.  I'm not familiar with the KoT.  I've heard of it, but that's all.  No idea why turning the left side on would kill the right LED.  Does the left LED come on?

[antonis]

According to your diagram, it shouldn't happen..!!

Even if the current for both LEDs wasn't enough, the LEDs should equally dim..

[natron_mn]

The weird thing is, every once in a while the bug doesn't occur. That is, when both sides are active, both LEDs are on. But then if I switch off one of the sides and reengage that side, the right LED once again turns off.

I don't know if you can tell from the picture of the pedal, but I twisted the two ends of the LEDRs together and then soldered those twisted ends into the 9V pad on the PCB. From the wiring diagram, it appeared that this approach was equivalent to the diagram's.

[thermionix]

That sounds more like a funky switch.  Looks like you wired it correctly.