Quoted from bobukcat:I seem to remember a solution for adding another leaf switch to the start button and wiring it to the coin-in switch wires so that every time you press start it also adds a credit.
^^^^ this works perfectly.
1. No need to change the replay value (changing the replay low makes the knocker go off- it is more fun to earn the knock)
2. Very cheap (no expensive new board or chip replacement)
3. Totally reversible and easy to install.
4. Fool proof option- works every time.