Found in an old Popular Electronics this circuit is still current. The SCR can be of the 106 series and the relay according to the voltage used in the supply. The voltage can be 12 V.
This circuit was found in an American documentation from 1969. It serves to trigger circuits by...
This input stage has unit gain but a high input impedance and low output impedance. The circuit is...
The circuit presented was found in the Linear Applications Handbook of the National Semiconductor of 1994....