We found this circuit in a 90s Popular Electronics. The circuit uses a pickup coil that consists of 100 to 200 turns of wire 28 around the cable to be monitored.
This circuit locks when the sensors are opened. The relay can be 6 or 12 V depending on the power...
The indicator instrument of this transistor tester, from an Argentine publication of the 1970s,...
Found in American documentation from the 90s, this circuit uses TTL technology and is therefore...