Installation (Cont.)
Ignition Noise Interference
Use of a mobile receiver at low signal levels is normally limited by the
presence of electrical noise. The primary source of noise in automobile
installations is from the alternator and ignition system in the vehicle.
Under most operating conditions, when signal level is adequate, the
background noise does not present a serious problem. Also, when ex-
tremely low level signals are being received, the transceiver may be
operated with vehicle engine turned off. The unit requires very little cur-
rent an therefore will not significantly discharge the vehicle battery.
Even though the COBRA radio has an automatic noise limiter, in some
installations, ignition interference and other forms of automobile gener-
ated noise may be high enough to make good communications difficult.
The electrical noise may come from several sources. Many possibilities
exist and variations between vehicles require different solutions to
reduce the noise. Consult your COBRA dealer or a 2-way radio techni-
cian for help in locating and correcting the source of severe noise.
Base Station Operation (Operation from 120VAC, House Current)
To operate your transceiver from your home or office, using the regular
house current as the power source, you will require a 12VDC power
pack that has been specially designed for the purpose. It is available as
optional equipment from your COBRA dealer. It consists of a 120-volt,
60 Hz AC to 12-volt DC power converter with a 3A rating. Simply con-
nect the red (+) and black (-) leads of the transceiver to the correspond-
ing terminals of the power packs.
DO NOT ATTEMPT TO OPERATE THIS TRANSCEIVER BY
CONNECTING DIRECTLY TO 120 VAC. SERIOUS DAMAGE
WILL RESULT.
Temporary Mobile Operations
To operate your COBRA transceiver from a car on a temporary basis,
you may want to purchase an optional cigar lighter adapter from your
COBRA dealer. This adapter and a magnetic mount antenna allow you
to quickly "install" your transceiver for temporary use.
Installation(Cont.)
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