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Schematic - Push Button Fire

Schematic - Microcontroller

The Build

I ended up using a Sonoff SV since it had everything I needed. Instead of having to use a transistor to switch the 12v, I used the built-in relay.  The Sonoff SV also has 3 GPIOs available which I used for a RGB LED. It also exposes the GPIO-0 (button) which I used for the foot pedal. The foot pedal made things so much easier.

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