This circuit operates at a voltage of 1.3 V from a single mercury cell. We found in an old documentation and for the components used the frequency is 500 kHz.
This set-rest relay uses two SCR and two switches to control a DC relay. The circuit can be used...
This control panel allows the use of NO and NC sensors, turning the alarm on after 30 seconds...
This circuit, from the 1990 Motorola Dataar Databook, can use any LM139 series comparator. The circuit...