1-minute delay (CB21408E)

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

Simple VHF Receiver (CB19598E)
This VHF receiver with three transistors and loudspeaker listening was found in European...
Liquid level sensor (CB23807E)
This sensor was published in Radio Electronics magazine in April 1962. The two-transistor circuit...
Monostable LM3900 (CB19295E)
This circuit consists of a monostable multivibrator using the LM3900 transconductance operational...