Matching antenna (CB7458E)

The coil and sockets of this circuit found in a QST depend on the frequency band that is intended to be tuned.

Interface for resistive transducers (CB20995E)
We found this circuit in an Analog Devices documentation from the 90s. The circuit is based on a...
Triac Timer (CB24046E)
This circuit turns off a load after an interval of 8 to 80 seconds adjusted on the potentiometer. The...
Simple Alarm with SCR (CB24114E)
Found elsewhere in this section, this circuit is from the April 1971 Radio Electronics magazine. Note...