It's been a long time since college physics and basic circuits so I'm hoping someone here can be of help. I have a pair of photocells that are used at the finish line when my club times whitwater slalom races. The photocell gives a short low voltage impulse when the beam is broken. I would like to add a buzzer to indicate to the racer when the line is crossed. I picked up a piezo buzzer at Radio Shack, but need help getting it wired in. I would like to use a 9v battery for the buzzer and keep the circuit as small as possible. I don't want the buzzer circuit to feed back into the impulse path as that is connected to a timer. Connecting to the photocell is easily done. I would also like to be able to get the parts at my local Radio Shack. Thanks for your help.
Andy
