1940s commercial receiver (T1618E)

This receiver was found in a Radio Electronics from 1949. It is a superheterodyne of the time using 6 tubes.

Telephone Call Monitor (CB10509E)
This circuit was found in a 1985 English magazine, but it can still be easily assembled, as the...
Sonic defense (CB8238E)
This powerful sound emitter used in defense to intimidate people was found in a 90s Popular...
Constant Voltage Source (CB24066E)
We found this circuit in the August 1970 issue of Radio Elecronics magazine. It uses the CA3018...