Over at Tiny Transistor labs, [Robo] took it upon himself to reproduce the classic 555 timer in discrete transistor form. For bonus points, he also managed to put it in a package that’s the same basic ...

The circuit was designed sensitive enough to trigger and activate the alarm upon sensing wetness, moisture or dampness on its probes. 555 Timer – an 8-pin electronic device used in several mixtures of ...

Whenever I use the 555 timer, it seems that the output polarity is invariably incorrect, and the way the 555 functions, it normally cannot generate a duty cycle of less than 50% — 90% yes, 10% NO!