Looking for a way to make a 555 timer astable circuit "triggerable." Seem
all the circuits I see (I think the some one over and over again) show an
astable 555 rigger to run constantly as a "clock." Right now I am using a
transistor to power up and down the 555, but it seems there should be a
better way. Basically I want "bursts" of pulses based on a trigger. (And it
needs to reset itself, not needing any manual reset.)

Thanks,
Henry