We found this circuit in a 1965 Electronic Design. Transistors are still common but admit equivalents for some of them. The circuit drains a current of only 4 mA.
This circuit can be used as a lockable shield. A pulse activates the relay that remains on even...
Found in a 90s documentation, this circuit makes use of D1, a switching diode that is uncommon today....
June 2017 - New Honeywell MT MICROSWITCH Series can be ordered from Mouser Electronics for...