Radar Detector Position.
the case of a
front facing radar detector
there are a number of locations
one could place a radar detector facing backwards in a Diablo. The
simplest option would be to simply attach the unit to the rear window
behind the drivers seat. I found this to be somewhat unsatisfactory
for two reasons. First the unit is very visible and open to been
stolen. More importantly I found it not to be very sensitive to radar
signals. For a radar signal to reach it, it has to travel under the rear
wing/spoiler up over the engine area and into the cabin area. This appears
to lead to a weak signal. I decided to place the unit behind the
radiator grill at the back of the car as shown in Figure 1. It is
important to place the unit on the extreme right hand side beside the tail
lights. The central region of this grill gets very hot and could damage
Please read a description of
placement before proceeding with the installation of a rear facing unit.
As before take care that the speaker leads do not short against the Bel circuit
Unlike the case of the forward facing unit,
the rear unit is exposed to the outside environment and thus has to be
made waterproof. The approach I used was to place the circuit board of the
Bel 980 unit in a custom plastic box (1" X 3" X 5" in
size). In the side of this box was cut a hole such that the LED display
could be pushed through.
Power Connection. A second
hole was made for a single 4 conductor cable. The red and black
speaker wires connected to the circuit board were removed and two of the
above four leads from the above cable were soldered to the board. The four conductor
cable should be at least 20 feet in length. The Bel units speaker is soldered to
the same pair of leads at the other end of the wire. Test the
speaker is working by applying power to the unit.
Next we need to
hookup the two remaining leads of our four conductor cable to the 12 volt
power supply to the unit. We need to make sure the +12 volt supply
goes to the internal ring of the radar power plug and the ground lead goes
to the outer ring of the connecting plug. Make absolutely sure you
get this right. Before you cut off the cigarette socket plug from
the power wire, plug it into the car. Determine which is + and which is
ground on this small plug using a volt meter. Write these down and
store. You can solder the leads directly to the circuit board or to the
plug socket lead. The latter takes up less room in the box but requires a
slight knowledge of circuit board layouts and a volt meter. In any
event again check the unit is functioning by applying power to the
unit. The sound and LED display should work.
Now we need to configure the unit to "Auto scan"
and "Quick Start" modes. Please read the Bel manual for details
as to how to do this. When you are sure you have things configured
correctly you can then seal the unit in the box using plastic glue. It is
essential the whole setup be completely waterproof. In particular seal
areas around the LED display and where the cable comes out of the
box. Figure 2 shows a unit ready for installation.
2. Waterproof custom box containing rear radar detector unit. Note
3. Top view of radar detector installed in Diablo. The unit is
glued to frame on two sides. A metal support is also used.