This simple circuit is powered by the logic circuit itself. Components are still common, although they were obtained from somewhat old documentation.
This 80's General Electric circuit is guarded by the noise-guard for operating current. The...
This two-door doorbell was found in a 1990s US publication. The circuit is still current as...
August 2017 - Rectron's Schottky Barrier Diodes can now be obtained from Mouser Electronics. The...