Published in an old Popular Electronics, this circuit makes use of components that are still current. The circuit must be powered with 9 V and eventually adapted to function as a shield.
Waking up to a loud and clear sound from an audio oscillator, after up to 5 hours of sleep, or...
This circuit was found in a publication from the 90s. The circuit can be assembled with modern...
This conventional oscillator with the 741 can be precisely adjusted to produce a 400 Hz signal. The...