We found this circuit in a 1969 General Electric documentation. The circuit uses transistors of the time and the diodes in the dotted board must be mounted on the output transistor heatsinks.
This is one of the many modulated siren versions that can be found on our website. We found it in a...
This circuit was found in the May 1983 issue of Radio Electronics magazine. The SSM7046 integrated...
This isolated shield uses a common optical coupler that supports several equivalents. The resistor in...