can hide the wire under baseboards
or at the joint of the baseboards and
carpet. Typically, a twisted pair from
each door module routes into the
basement, and the series loop is
completed with a few well-placed
junction points.
You can use two different
methods to mount the indicator
LEDs. The first is to drill a hole in the
casing for the LED as in Figure 6. In
this case, mount the LED vertically on
the prototype board. Then, pull off
the door casing and press the LED
through the hole in the casing so that
the circuit board is tight against the
back of the casing.
Hollow out a space in the
sheetrock for the circuit board so the
casing can go back tight against the
wall. Once you get the switch and
I/O connectors to the circuit board,
the casing can go back on.
If you don’t want to disturb the
casing, you can mount the door
circuit and LED as shown in Figures 7
and 8. The circuit is contained in a
short section of 1” PVC tubing with a
1.5” diameter PVC face plate. Use a
1” hole saw to put a hole in the
sheetrock about 1.5” past the edge of
the casing (to avoid door frame
studs). This hole should be centered
on a horizontal line to the center of
the dead bolt. When you get the
June 2017 25
■ FIGURE 6. A dead bolt lock and its associated
indicator mounted in the door casing.
■ FIGURE 8.
The diode
logic circuit
board
installed in a
homemade
PVC module.
■ FIGURE 7. Security indicator located in the sheetrock adjacent to a
deadbolt lock.
