Hartley for 1 MHz (CB25588E)

This oscillator was found in the July 1993 Electronics Now magazine. The coil is wound with 28-wire in a 0.5 cm shape.

Projector control (CB8299E)
This old slide projector control circuit was found in an 80s Hands On. The circuit uses modern...
SUS Frequency Divider (CB19903E)
In the figure we have a circuit that uses unusual components, being indicated for low frequency...
Rain alarm (CB6955E)
The sensor of this circuit found in Popular Electronics can be formed by a piece of fabric between two...