General Information; Antenna Systems - GE 3-5875A Use And Care Manual

GENERAL INFORMATION
CB's MANY USES
23 channels of Citizens Band (two-way) Radio were approved by the
FCC in 1958 and expanded to 40 channels in 1977 to be used by
private citizens for personal and business communications.
CB radio is easy to understand and operate. There is nothing technical
you must know. . . no more than what it takes to use a telephone or
operate any standard AM or FM radio.
When communicating with your CB, always be brief, never use
profanity (against the law and carries severe penalties), and follow the
FCC rules as outlined in Part 95.
Here are some of the many uses for CB radio:
.
Personal or Family. Keep in touch between your car, home,
friends, and neighbors.
.
Hunting, Fishing, or Camping. Talk between campsites, to fishing
boat, boat-to-shore, hunting parties, or camper-to-camper.
.
Travel and Vacation. Request directions when you are lost on the
highway, need help to repair a flat tire, or to report an emergency.
.
Security. Some cities have established a Volunteer CB Patrol that
provides concerned citizens with a communication line t6 local
police for reporting suspicious or criminal activity.
.
Business Use. Save time and extra trips: call your office for
messages.
.
Sales and Service. Save valuable time by using CB for those quick
contacts or confirming appointments.
.
Truckers, Deliverymen, Farmers, Ranchers, or Construction
Crews. Whether you're calling for road and traffic conditions, farm
tractor to house, or coordinating work crew activity, two-way radio
can play an important role.
SINGLE SIDEBAND
Conventional 40-channel (AM) units operate on a transmitted signal
consisting of three parts: CARRIER, UPPER SIDEBAND, and
LOWER SIDEBAND. Both UPPER and LOWER SIDEBANDS are
located on either side of the CARRIER and contain identical informa-
tion (all the audio) being transmitted.
Single sideband transmitters cancel out the carrier and one sideband,
and devotes the final stage to transmitting only one of the sidebands.
That is, all the wattage would be used to transmit the selected
sideband. This results in perhaps twice the useful transmit range of
conventional AM.
Points of Interest:
1. Since the operator of an SSB unit has the option to select either
upper or lower sideband on which to transmit for each CB channel,
he effectively has twice as many transmission paths or "channels"
as an AM operator. (Note: AM does overlap or interfere with SSB
on the same channel, so the 80 SSB "channels" are not new,
independent transmission paths.)
2. Since the carrier is not transmitted on SSB, the receiver must
recreate a "carrier" to en'able demodulation. Since this recreated
carrier must be accurately on frequency, a "clarifier" control is
necessary to fine-tune.
EMERGENCY CHANNEL 9
A major beneficial use of CB radio is for public safety purposes.
The Federal Communication Commission has issued "call signs" that
include "0911" numbers to public safety agencies. These numbers
coincide with the "911" telephone numbers coming into greater use by
public safety agencies (state police) for telephone communications.
The call signs for state-level agencies use 3 letters and 4 numbers,
with the second and third letters being the official Post Office state
abbreviation, and then the number
"0911"
(e.g., KMO-0911 for
Missouri, KIL-0911 for Illinois).
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ANTENNA SYSTEMS
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ANTENNA SYSTEMS
For best reception and transmission, your CB transceiver should use
an antenna especially designed for a frequency of 27 MHz. Antennas
are purchased separately and include installation instructions.
Numerous types of CB antennas are available that range from
emphasis on ease of installation to emphasis on performance. Often
the difference in performance between many of the antennas is
modest.
Your transceiver has two standard antenna connectors: type SO-239
(located on rear panel) for easy connection to standard PL-259 coax
plugs. If the coax antenna cable must be made longer, use coax cable
with impedance of 50 ohms, frequency ratings for 27 MHz, and use
only enough cable to suit your needs. This will insure a proper
impedance match and maximum power from the transmitter to the
antenna.
BASE STATION ANTENNAS
When using this CB transceiver as a base station, any Citizens Band
ground plane, beam, dipole, or vertical antenna may be used. The
range of the transceiver depends basically on the height of the an-
tenna. Whenever possible, select the highest location within the FCC
limits.
NOTE: You can connect 2 antennas to your CB, or 1 antenna and one
dummy load. See Accessory Order Form.
GROUND PLANE
BEAM
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COAXIAUCOLlNEAR
GROUND PLANE antenna is the most commonly used antenna for
base stations. It is fairly effective, omni-directional, lightweight, easy to
mount, and economical. It is designed for medium-long range com-
munications.
COAXIAUCOLlNEAR antenna is a high-efficiency radiator with im-
proved omni-directional characteristics. It provides an effective in-
crease in power when compared to a regular ground plane antenna. It
is designed for medium-long range communications.
BEAM antenna is highly directional and must be used with a rotor
unless you are communicating with a fixed station. Since it is direc-
tional, it greatly reduces noise and interference from all other direc-
tions. The increased forward gain and the higher front-to-back ratio
results in an effective power gain many times that of a standard ground
plane. It is designed for long range communications.
Whatever type of antenna you choose, ground the antenna mast and
connect a lightning arrestor to the coaxial lead-in. This will protect your
system and reduce static interference.
Follow all safety
instructions
when
installing base station antenna.
Use coaxial cable rated for the 27 MHz frequency when connecting
your base station antenna to the transceiver. Use proper connectors
and terminate them well when installing the antenna system. Usually
RG-58/u cable is adequate up to 50 feet. If installation requires over 50
feet of cable, use RG-8u type to reduce any in-line signal loss.
Antenna cable can also act as the antenna, so keeping length to
minimum not only reduces signal loss from cable, but also pick-up of
static signals.
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