Ignition Noise Interference
Antennas
Use of a mobile receiver at low signal levels is
normally limited by the presence of electrical
noise. The primary source of noise in automobiles
is from the alternator and ignition system.
Typically, when signal level is adequate, the
background noise does not present a serious
problem. Also, when extremely low level signals
are being received, the transceiver may be
operated with the vehicle’s engine turned off. The
unit requires very little current and therefore will
not significantly discharge the vehicle’s battery.
Even though the Cobra 29 LTD HD LE has an
automatic noise limiter, in some installations
ignition interference may be high enough to
make good communications impossible. Many
possibilities exist and variations between vehicles
require different solutions. Consult your COBRA
dealer or a 2-way radio technician for help in
locating the source of a severe noise.
CB Antenna
Since the maximum allowable power output of
the transmitter is limited by the FCC, the antenna
is critical in affecting transmission distance. Only
a properly matched antenna system will allow
maximum power output. Cobra loaded type
antenna models are highly recommended for
most installations. Consult your Cobra dealer for
further details, or call 773.889.3087 and speak to
a Cobra representative.
Marine Installation
The transceiver will not operate at maximum
efficiency in a boat without a ground plate,
(unless it has a steel hull). Before attempting
installation , consult your dealer for information
regarding an adequate grounding system and
prevention of electrolysis between fittings in the
hull and water.
CB Antenna
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Note
For optimum performance in
passenger cars the ideal
antenna location is on the
center of the roof. Second
choice is on the
center of the trunk.
Note
Because many newer trucks
feature fiberglass door skins, the
outside mirror must be
grounded to the chassis via a
ground strap when antenna is
mounted on the mirror bracket.
Note
3-way Combination
Antennas are also available
which allow operation of all
three bands (AM-FM & CB),
using a single antenna.
However, this type of antenna
usually results in less than
normal transmit and receive
range when compared to a
standard-type “Single Band” CB
antenna. Call 773-889-3087 for
further information.
6
1
A standard antenna connector is provided
on the transceiver for easy connection.
All manuals and user guides at all-guides.com
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