Bench thermometer (CB20501E)

With an ultra-low consumption, this circuit can be powered by solar cells. The circuit is from a 1991 documentation.

Radiation Monitor (CB4561E)
This circuit was obtained from an 1974 Everyday Electronics magazine. The circuit is still current as...
Super heterodyne input stage (CB8393E)
Found in a 90s Popular Electronics, this circuit uses components from that time, for a...
Tone Generator for Remote Control (CB526E)
The output of this circuit can be coupled to a radio control transmitter to perform a...