Regulated supply for tube heaters (CB23725E)

This power supply for tube heaters was found in a January 1961 Radio Electronics. The circuit uses a power transistor from the time.

Temperature Sensitive Touch Switch (CB10236E)
This circuit was found in a 1987 edition of the United States' Hands-On Electronics magazine. The...
250V x 600 A series regulator (CB8820E)
This circuit was found in a 1966’s Delco Radio documentation. Transistors are from the era, high...
Triac LDR photo control (CB8327E)
Found in a 1960s RCA documentation, this circuit applies to most common triacs. The trigger device is a...