Signal Tracer and Capacitor Tester (T1241E)

This mains powered two-in-one instrument was found in a Radio Craft from March 1948. The headphone must be high impedance.

Solar radio (CB22491E)
This receiver for medium wave range with germanium transistor was found in a documentation from...
Low consumption monostable relay (CB9163E)
Found in an Elektor from the 90s, this circuit makes use of current components. The input voltage...
High Voltage Inverter (CB23523E)
The original purpose of this 1963’ circuit from a magazine is to replace the mechanical vibrators used...