1-minute delay (CB21408E)

This circuit with PUT is from a 1967 General Electric manual. The relay must have voltage according to the supply.

FET and Bipolar Amplifier (CB18870E)
This good power amplifier was found in a Japanese magazine from the 1970s. The circuit uses...
Light operated switch (CB8321E)
This circuit was found in 1960s Radio Electronics. The circuit uses components from that time. The...
Variable Phase Counter (CB24763E)
This circuit for counting down pulses was found in the September 1983 issue of Radio Electronics...