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REPLACING THE BULBFINAL STEPS. Screw on the contact arm. Then complete these circuit connections: Run one doorbell wire to the battery, the other doorbell wire to the contact arm, and a third line from the upper contact screw to the battery.
A WATCHDOG THAT NEVER SLEEPS. The system should work like a charm. Anyone opening a door that is booby trapped with this alarm will be in for quite a hair-raising surprise. Keep in mind, too, that this burglar alarm is truly portable. Since it has its own power supply, you can take it on family trips for use in hotels, motels, or house trailers. Maybe everyone will sleep with more peace of mind.