I modified my first machine with an autostop chip and it works great. However after playing with it for a while, I've decided that I like stopping the reels myself. I do like the credit add feature. I've read of several ways to add this feature on your own. Those being the switch on the coin hopper for automatic dispensing, rerouting the tokens so they fall back to the tray and I believe that someone added a switch to the optical comparator(s) to fool it into thinking that the coins have passed. I really like the last option, but the 2 machines I have (NET and Macy) have 2 optical devices. I assume that one tells it that a coin enters and the other tells it that it passed, so it would require some type of double pole switch or relay.

Has anyone played with a switch like this or are there other more simple ways to do this?

How do you do add credits to your machine and what are (were) the pitfalls of doing it your way?