This sensitive circuit was found in the August 1971 issue of Radio Electronics magazine. The SCR is equivalent, and the transistor may be a BC548. The load may be a relay.
The A3906 integrated circuit from Allegro MicroSystems (www.allegro.com) consists of a single-step motor...
We found this circuit in a 1980s publication on telephony. The circuit uses an integrated...
This circuit can use a pendulum sensor. We found this configuration in a 1994 publication. The...