AES 3-Button Footswitch

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AES 3-Button Footswitch

Post by dorrisant »

I have one of these switches and wanted to change the state of the LED for the Tremolo on my footswitch. I read and followed the advice from here: ... h&start=15
and here: ... footswitch

I have used these before and never had to change the LED state.

I had this FS working, changing channels reverb and tremolo off and on... no problem. Then I changed the LED state for the tremolo switch and I get a weird issue. The tremolo relay will cylcle from off to on by pushing the switch once, then stays on (ground lifted from tremolo stop) while the LED cycles on and off with each push of the switch. So, the pilot for the tremolo acts normal but the relay gets stuck on.

Positive DC from the supply is daisy-chained to the positive terminals for the relay coils (determined by the polarity of the protection diode). I know that these relay coils are not polarity sensitive. The relay coil ground shows different readings for the LED on/off states.

Channel relay OFF = 0.29v DC = LED OFF
Channel relay ON = 4.98v DC = LED ON

Reverb Relay OFF = 0.27v DC = LED OFF
Reverb Relay ON = 4.98v DC = LED ON

Tremolo Relay OFF = 0.26v DC = LED OFF
Tremolo Relay ON = 2.76v DC = LED ON

I'm using a supply that has -2.5v and +2.5v nodes for the +5v DC, Omron G5V-2 Relays for all three. And no, the -2.5v DC side is not connected to ground in any way.

The 1k limiting resistors seem to be a little large, meaning smaller would shine brighter. The diagram from one of the links above is what I followed. I used 150Ω in parallel with the diode for the tremolo switch. Is the fact that I'm using 5v relays as opposed to 12v relays the thing that is biting me? Maybe I'm missing something. Let me know if you see anything that I seem to have missed.
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