Triac driver (CB22446E)

The presented circuit uses an optocoupler to trigger a triac. We found it in a Popular Electronics from 1992.

Transistor gain meter (CB21952E)
We found this circuit in a Gernsback documentation from 1960. The circuit is intended for...
Broadband Booster (CB23667E)
The frequency range of this circuit depends on the transistors used. The circuit is from a Radio...
Signal Tracer (CB921E)
This circuit consists of a good perfromance audio amplifier powered from two or four batteries and has...