We found this CMOS circuit for excitation of a relay in an old documentation. The transistor is a general-purpose high voltage as used in the power supply.
Found in a 90s ARRL Handbook, this circuit is intended for the production of signals in the side...
This thermostat was found in a 1997 publication. It can be powered by 6 V with the use of a...
This simple alarm with latching uses a relay as the main element. The circuit is from a Radio...