Suggested modernistic cabinet for police call alarm is given above, left.
Paint edges aluminum, sides glossy black enamel.
Mounted in attractive cabinet atop regular receiver, this police call alarm automatically brings in local police calls over regular programs. One tube circuit is used. With this radio call alarm connected to your broadcast receiver you can listen in to broadcast programs at any time, yet hear every police call sent out from your local police station without touching the receiver controls. These calls are heard with enough volume to make them easily understood regardless of the type of program being received, provided the police radio station is within ten miles of your home. The alarm is simply a regenerative detector circuit tuned to the police wave band and coupled into the audio circuit of your receiver.