This receiver was found in a Radio Electronics from 1949. It is a superheterodyne of the time using 6 tubes.
MCP19124/5 Contains Independent Voltage and Current Control Loops Plus a Full Suite of...
A modulated (flashing) siren using the four gates of the 4001 integrated is shown in the figure....
Several types of OSEPP sensor modules can be obtained from Mouser Electronics for Arduino...