■ FIGURE 1.
Figure 2. It also wakes up every 2. 3 seconds and looks for
a valid transmit signal and code for 20 microseconds. If
there is none, it goes back to sleep. It counts four 2. 3
cycles and then flashes either green or red indicating the
door positions. If it receives a signal from the transmitter, it
changes its display and will flash the LEDs until the
transmitter stops its transmission.
Both micros control the transceiver’s power using the
PDN line control. The T/R SEL pin differentiates between
sent data and received data.
Construction
Boxes
Go to the downloads link indicated here and
download Garage. There are templates included in the
attached files. Print and cut them out. With the two halves
together, turn the box over and locate the battery holder
area. Place the battery area towards you and turn the box
face up. The board and antenna go on the far end as
shown in Figure 3. (The box will not go together if the top
half is reversed). Using a glue stick, glue the antenna
template, front panel template, and side templates to the
box. Using a drill press, drill the proper size holes as
indicated on the templates. The receiver box is done the
same way, however, there are no side holes; only the front
panel and antenna. After the holes are drilled, use hot
water to remove the templates and glue.
Transmitter
On the top of the board, mount the Linx module first,
then the microprocessor, capacitor, terminals, and the
voltage detector. The tilt switch is mounted on its side
with its terminals toward the edge of the board. The
transducer is mounted on the bottom of the board. Look
at Figure 4. Note the polarities on the components which
require them. Thread the wires from the battery holder
through the slots of the battery compartment, through the
antenna, and place it through its hole. Add the board over
the antenna and secure with a screw. Use two self-tapping
screws to secure the board to the box.
■ FIGURE 2.
Receiver
On the top of the board, mount the Linx module first,
then the microprocessor, capacitor, resistor, and the
voltage detector. Add the transducer, LEDs, and the switch
on the bottom side. The best way to insure the correct
length of the LEDs is to place them in the board, place the
board in the box, seat them in their holes, and solder the
leads. Take a look at Figure 5. As above, solder the battery
holder wires and install the antenna.
■ FIGURE 3.
November 2010 39