This interesting digital counter with relays with complementary outputs was found in the Radio Electronics magazine of October 1961. The supply voltage is in accordance with the relays used.
This circuit is from a June 1992 Radio Electronics. The circuit is for 4.5 MHz signals from old...
This circuit, calibrated to the degree Celsius scale, was found in a National Semiconductor...
The photocontrol that we give in this project of a 1982 documentation allows to activate a circuit...