This circuit from a 1966 General Electric manual makes use of an SCS. The time is given by the emitter capacitors of the unijunction transistor.
This amplifier was found in a Japanese publication in 1972. Transistors are uncommon today, and...
The current of this source is 200 mA at the most, and the output depends on the zener that may...
Found in Mallory documentation from 1968 this circuit uses an integrated circuit from that time. The...