Found in an Elektor from the 90s, this circuit can be powered directly by the power grid. The circuit uses a rectifying bridge that can be replaced by 4 common diodes.
This circuit produces the ticking of a clock on a common piezoelectric transducer. The circuit has an...
The basis of this circuit is a double T in the feedback, which has the components calculated to...
This configuration was found in the Texas Instruments optoelectronics manual. PNP transistors...