This circuit converts infrared pulses into audio and can be used in an experimental telegraphic link. The circuit is from a Popular Electronics from the 90s.
This 10-minute timer was found in the July 1994 Radio Electronics magazine. The relay must be...
This oscillator generates a sinusoidal tone of 1750 Hz determined by the twin-T. The circuit can be...
This is a basic inverter circuit for a 70 kHz crystal. We found it in an old documentation using an...