This 32 A circuit uses SCRs of the time. We found it in a 90s General Electric documentation. The transformer is a commercial type of the time.
Found in a 90s Popular Electronics, this circuit checks if a remote-control transmitter is...
This relay circuit with a dual channel MOSFET (not very common today) was found in an old American...
This application is not modern since few computers have parallel ports. But you can use this...