Simple 1-tube receiver (T960E)

This 1V heater tube circuit was found on a Radio Craft from 1945. The circuit is for medium wave and can be used as a tuner.

Electronic Relay (CB504)
circuit is used to increase the sensivity of a relay. A 50 to 100 mA relay can be triggered with...
Night Switch (CB12331E)
With S1 closed, when dark, the triac will supply the load with the power set in R4. The LDR is...
12 V regulator with 1 A (CB9155E)
Found in an EDN from the 90s, this regulator makes use of the integrated circuit of the time. The...