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CB's MANY USES
CB radio is easy to understand and operate. There is really nothing technically 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
follow P & T rules.
Here are some of the many uses for CB Radio:
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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.
•
Remember, the biggest party line ever is CB (for listening Fun).
SINGLE SIDEBAND
Conventional 18 channel (AM) units operate on a transmitted signal consisting of 3 parts;
CARRIER, UPPER SIDEBAND and LOWER SIDEBAND. Both UPPER and LOWER SIDE-
BANDS are located on either side of the CARRIER and contain identical information (all the
audio) being transmitted.
EXAMPLE:
A unit with 3 watts RF output modulated 100% (maximum audio), the useful transmitted
power is only 1/2 watt (either sideband).
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 3 watts would be used to transmit the
selected sideband. This results in, perhaps, twice the useful 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
(NOTE: AM does overlap or interfere with SSB on the same channel, so the 36 SSB "channels"
are not new independent transmission paths).
2. Since the carrier is not transmitted on SSB, the receiver must recreate a "carrier" to enable
demodulation. Since this recreated carrier must be accurately on frequency, a "clarifier"
control is necessary to fine tune.
3. Conventional AM receivers use AGC circuitry to guard against overload signals. But AGC
needs a transmitted carrier to work. Thus, SSB units do not have AGC and instead, have an
RF Gain Control so the operator may manually adjust level of incoming signals.
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