This timing circuit was found in old documentation. The technology is CMOS. The supply can be made with voltages from 3 to 12 V. The time depends on R1 and C1.
This circuit was obtained from the 1976 Siemens integrated circuits manual. It is the circuit for...
The circuit is Motorola's 1974 Unijunction Trigger Circuits for Gated Thyristor. A 2N2646 can be...
With the configuration shown in the figure, we have the relay being activated when the microphone picks...