Passive Autofire

A cunning little autofire circuit based on a 74HC04 hex inverter that uses the voltage supplied to a button for power. While it does have a miniscule "pause" in fire rate every second or so, it's excellent for use with most games and is incredibly cheap to produce.

Schematic

Thanks to Yosai for drawing this

Usage

1. Unplug the GND from a button on your panel
2. Plug the spade connector from the circuit into the GND wire connector in your harness
3. Connect either blue wire to the GND on the button
4. (Optionally) connect the second blue wire to yet another button by disconnecting it's GND

Photos

• 
  In detail
• 
  74HC04 IC
• 
  100uF 16V capacitor
• 
  Resistors and potentiometer
• 
  Clone (by Yosai)