- 1). Raise the window. Place a sensor plate against the bottom of the window and screw it in with wood screws using a Phillips screwdriver. Close the window. Draw a line, using a grease pencil, against the edge of the bottom of the window where the sensor plate has been attached. Raise the window again.
- 2). Place the sensor plate attached to the wireless transmitter on the windowsill, over the line that was drawn, so that it is now even with the plate on the bottom of the window. Screw the sensor plate into the windowsill with wood screws using a Phillips screwdriver.
- 3). Open the battery compartment lid on the bottom or back (depending on the manufacturer) of the wireless transmitter; if there is a screw on the lid, remove it first with a Phillips jeweler's screwdriver. Insert a battery or batteries (depending on the manufacturer) into the battery compartment. Close the battery compartment lid and reattach the screw if one is present.
- 4). Place the wireless transmitter against the wall, beneath the windowsill. Do not stretch the cable going from the sensor plate to the transmitter. Screw wood screws through the slots in the transmitter to the wall with the Phillips screwdriver. Slide the selector switch on the side to "On" or press the "On" button, depending on the manufacturer. If there is no button or switch, ignore this step. Slide the "Channel" switch to the "1" or "2" channel, depending on your preference. If there is no "Channel" switch, ignore this step.
- 5). Place the wireless alarm receiver near your bed where it can sit undisturbed. Plug the power cord from the receiver into a wall outlet for power. Slide the "Channel" switch to the "1" or "2" channel, depending on what the transmitter's "Channel" switch was set to. If there is no "Channel" switch on the transmitter, ignore this step. Slide the selector switch on the side to "On" or press the "On" button, depending on the manufacturer. The alarm will now sound if anyone raises the window that's now protected.
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