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|To activate the alarm, simply turn the radio’s power
switch to “on.” If any of the window or door switches
are “triggered,” the radio will instantly sound a warning.
Reset the alarm by replacing the pulled-out piece of
Instead of a radio, you can use an electric bell as the signal device. You’ll need a “front door bell” (sold in hardware stores) and a 6-volt battery. The fifth diagram shows how to wire the bell and battery to the window and door switches.