potential hall sensor cheat?

[Miscue]

You guys are makig this way too complicated. The 555 thing would produce a recognizable audio signature, and would interefere with the motion of your fingers, (remember an astable 555 must haev duty cycle of over 50%)

Just connect the NC and NO leads on the switch with an HES. Works like a charm. Split off +9v and drop down to 5 or so with a 680ohm resistor. (better safe than sorry)

The boards out there already have a "recognizable audio signature," and the refs have been letting them on the field for quite some time. But yeah, the 555 I don't think would be practical - without a more complicated way of using it.

Let the software do all this stuff! You can do it other ways, but I don' t see why you'd want to other than novelty.