Sound Detector Latch
for use with the sound detector circuit/electret mike amplifier. when the 555 ic goes into timing mode (triggered by an output signal from the sound detector amplifier,) the timer's output (pin 3) is set into HIGH for a duration set by C2, and R2. adjusting R1 will adjust how long it listens, from 10 seconds all the way down to 2/10ths of a second. this could be used to listen for hand claps.