AUTO ALARM
The auto alarm senses the door being opened because it is connected to the interior light power. Opening the door starts a timer which will blow the horn unless the key switch is turned on before the time runs out. When leaving the vehicle, a longer time is allowed to close the door and avoid setting off the alarm. Two burgle loops are provided, which can be connected to the radio or other appliance, and will blow the horn when the wire is removed. Jumpers on the PCB allow the entrance and exit times to be selected.
Logic Schematic and Parts List
One Sided Printed Circuit Board Layout
