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Posted-By: auto-faq script
Archive-name: cb-radio-faq/part2
Rec.radio.cb Frequently Asked Questions (Part 2: Getting Started)
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[Last modified 4/15/92]
Questions discussed in Part 2: (dates indicate last modification)
* What is CB? (1/92)
* Do I need a license to operate a CB radio? (4/92)
* What are the CB Frequencies? (3/92)
* What are the common brands of CB radios? (3/92)
* What should I consider when choosing a location for my antenna? (1/92)
* Once I hook up my CB and antenna, is the radio ready to use? (2/92)
* What are good antenna characteristics and what are some good antennas? (3/92)
--Rec.radio.cb Frequently-asked Questions-----------------------------Part 2--
* What is CB?
-------------
CB stands for "Citizen's Band" radio. It got that name because its main idea
is to be a kind of radio anyone can use. Depending on the country you live
in, it is either a minimally-regulated or an unregulated set of radio channels
used for short-range (local) communications. Many people use CB radios in
their vehicles, homes or both.
This UseNet newsgroup, "rec.radio.cb," is all about CB radio. Readers can
expect to find discussions, questions, and answers about CB here. There are
also other newsgroups for other radio applications, such as rec.radio.shortwave
and several subgroups of rec.radio.amateur, for amateur or "ham" radio. Radios
either wanted or for sale are the subject of rec.radio.swap. (Though, an
article about a CB radio for sale should be cross-posted to rec.radio.cb and
rec.radio.swap with a distribution limited to your city, state or province.)
* Do I need a license to operate a CB radio?
--------------------------------------------
The answer to this question depends on the country you reside in. We currently
have information on the US, Australia, the UK, Japan, France, and Germany.
--- in the US
You are no longer required to have a license to operate a CB radio in the
United States. The FCC (Federal Communications Commission) did at one time
require a Class "D" license for for Citizen's Band which required nothing more
than filling out a form and sending it in to the FCC with the license fee. The
FCC then sent you a call sign which might look like "KPS 2720" or something
similar. During the CB craze in the mid-70's, the FCC decided that the paper-
work burden outweighed the benefits and put CB under blanket authorization.
The FCC permits the use of the following to identify yourself:
a. Your old Class D callsign, if you have one.
b. K, your first and last initials, and your zip code (i.e. KPS 68123)
c. your name (i.e. "Paul")
d. some unique nickname or Handle (i.e. "Cobra", "Rubber Duck", etc.)
--- in the UK, Japan, and Germany
No license is required. You may identify yourself by your name or a handle
of your choice.
--- in Australia
Australia's CB regulations are similar to what the US had before it deregu-
lated CB. A license is required but there is no examination. We are looking
into more details - if the government issues you a callsign, you have to use
it to identify yourself. Otherwise, you may identify yourself by your name
or a handle of your choice. We have not received any more details from our
source in Australia that brought this to our attention - if anyone else can
fill in more details, please send them to us.
--- in France
You are required to obtain a license but there is no examination. At the time
of this writing, the license costs 190FF every 5 years. You have to send
France Telecom the "agreement number" from your radio. Once on the air, you
may identify yourself by your name or a handle of your choice.
--- notes for all countries
There are rules and regulations that must be complied with while using CB, no
matter which country you live in. If you don't have a list of those rules
(which most likely were included with your CB), you will probably find them at
any store that sells CB radios.
* What are the CB Frequencies?
------------------------------
The answer to this question depends on the country you reside in. We currently
have information on the US, Canada, the UK, Australia, Japan, France, and
Germany.
--- in the US
Legal CB transmitters use the operator's choice of AM (amplitude modulation)
(with 4 watts maximum power) or single sideband (with 12 watts maximum power)
on the following frequencies.
frequencies (MHz) modulation description
26.965 - 27.405 AM/SSB 40 channels, max power 4W AM, 12W SSB
1=26.965 11=27.085 21=27.215 31=27.315
2=26.975 12=27.105 22=27.225 32=27.325
3=26.985 13=27.115 23=27.255* 33=27.335
4=27.005 14=27.125 24=27.235* 34=27.345
5=27.015 15=27.135 25=27.245* 35=27.355
6=27.025 16=27.155 26=27.265 36=27.365
7=27.035 17=27.165 27=27.275 37=27.375
8=27.055 18=27.175 28=27.285 38=27.385
9=27.065 19=27.185 29=27.295 39=27.395
10=27.075 20=27.205 30=27.305 40=27.405
* Channels 23-25 are not in ascending order due to historical reasons. CB
started with only 23 channels. Later, 24 and 25 filled a gap between 22
and 23 and 26-40 were added in ascending order.
Special-use channels:
9 - emergency, monitored in some areas by "REACT", a volunteer group
coordinated by the local Sheriff's office (not in all areas)
17 - unofficial "trucker's" channel (California & western U.S.)
19 - official "trucker's" channel for traffic and speed trap advisories
30-40 - Often are used for single sideband (SSB) activity
Note that US regulations disallow "DX" long-distance communications (over 150
miles in this case) with CB.
--- in Canada
We don't have specific information on Canada but, "reading between the lines"
on articles posted from Canada, we believe that made-for-the-US radios are
legal.
--- in the UK
The UK has 2 bands for CB as follows:
Legal CB transmitters use FM (frequency modulation) in either of 2 bands:
frequencies (MHz) modulation description
26.965 - 27.405 FM 40 channels, same frequencies as US
27.6 - 27.99 FM 40 channels, 0.01 MHz (10 kHz) spacing
AM and FM are not compatible so a US-legal CB cannot communicate with a
UK-legal CB even though they may use the same frequencies. And each is illegal
on the others' soil so this only prevents use of atmospheric skip between them.
FM is legal on CB in most or all of Western Europe so a UK CB can communicate
with those from the mainland if they are in proximity to do so. This will
usually be the case only if someone takes their CB across the English Channel
or North Sea. Make sure your CB is legal in the other country before trans-
mitting (i.e. power output, modulation, licensing, or other regulations.)
--- in Australia
Australia has 2 bands for CB. The use of AM or FM depends on the band.
frequencies (MHz) modulation description
26.965 - 27.405 AM/SSB 40 channels, same frequencies as US
max power: 4W AM, 12W SSB (same as US)
476.500 - 477.475 FM 40 channels, .025 MHz (25 kHz) spacing
As the first of the two bands above shows, made-for-the-US CB radios are legal
in Australia.
The following AM/SSB band frequencies have special uses either by regulation
or by common usage:
Channel 8 Road channel (truckers)
Channel 9 Emergency (same as US)
Channel 11 AM calling
Channel 16/LSB SSB calling, also used for DX (distance)
Channel 35/LSB unofficial additional SSB calling, also for DX
--- in Japan
Japan has 3 radio frequency bands that do not require licenses. Two of them
are limited to extremely short-range use because of low power limits. The
other, with maximum power output of 5 watts, is more like CB as it is known in
North America, Europe and Australia.
frequencies (MHz) modulation description
26.968 - 27.144 AM (no SSB) "Citizen's Radio" maximum power 0.5W
channels 1-8 on 26.968, 26.967, 27.040,
27.080, 27.088, 27.112, 27.120, and 27.144.
Other channels in between these are assigned
to fishing vessels (with 1W max power).
422.200 - 422.300 FM "Specific Low Power Radio", also known as
"UHF CB" maximum power 0.01W (10mW)
9 channels with 12.5 kHz spacing.
newly-authorized in 1989, mostly used for
handy-talkies and ski patrols
903.0125-904.9875 FM "Personal Radio" maximum power 5W
158 channels with 12.5 kHz spacing
External antennas are permitted.
Radios must be equipped with a control ROM
for automatic ID.
As in the UK, made-for-the-US CB radios are illegal in Japan. There have
been cases where such radios have caused interference with maritime emergency
traffic.
--- in France
France uses the same frequencies (in 40 channels) as the US but also allows
FM in the same band. The only legal CB radios in France are those which are
approved by France Telecom.
frequencies (MHz) modulation description
26.965 - 27.405 AM/SSB/FM 40 channels, same frequencies as US
max power: 1W AM and 4W FM (we don't have
the max power for SSB - inquire locally)
Channel 9 AM used to be for emergencies but was deregulated because no one
monitored it for that purpose. Channel 19 AM is the calling channel (used to
establish contact then move to another channel.) Channel 11 FM is used for
DX/skip long-distance contacts. AM is the more commonly-used modulation
method in France.
--- in Germany
Germany also uses the same frequencies as the US. AM and FM are the only
legal modes of modulation. (SSB is not allowed.) AM is only allowed on some
channels.
frequencies (MHz) modulation description
26.965 - 27.405 AM/FM 40 channels, same frequencies as US except
that Channel 24 is 27.245 MHz and Channel
25 is 27.235 MHz.
max power: 1W AM and 4W FM
AM is allowed on Channels 4-12
FM is allowed on all 40 channels
All signals must have vertical polarity.
Channel 9 AM is the calling channel.
Notes: to meet the vertical polarity requirement, antennas must stand vert-
ically. Also, tone-call transceivers are allowed so you can use touch tones
to call someone if they are within receiving range and have a radio that will
recognize the tones.
--- in other western European countries
This is the "grab bag" section. We have incomplete information on these
countries but we'll tell you what we've heard. We'll add more information as
people send it to us.
* Italy uses AM and FM like France and Germany. Channel 19 is the calling
channel. Channel 9 has no special designation (i.e. it is not an emergency
channel.) Italy also has some other unregulated frequencies but we don't
have any more information.
* Channel 19 is the calling channel in the Netherlands, Belgium, and Sweden.
* From the context of a news article, we assume CB radios in Sweden and
Finland must be "CEPT approved". We guess that means AM/FM and specifies
power limits on each.
* What are the common brands of CB radios?
------------------------------------------
Some of the more common brands that you will find out in the US market are as
follows: Uniden, Cobra, Midland, Realistic (Radio Shack), Archer (Radio Shack)
and others. Made-for-the-US radios are also legal in Canada and Australia.
We currently don't have any corresponding information for Europe or Japan.
* What should I consider when choosing a location for my antenna?
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The answer to this question differs greatly between base and mobile installa-
tions. Each will be answered separately.
In mobile installations, things to consider are whether you're willing to
drill holes, use a magnet mount, or use a bumper mount. If you say "no" to
all of those (which would probably mean you have a very nice car) your list of
options is pretty short - use a handheld with a rubber duck antenna.
Otherwise, you can start making choices with the following things in mind:
1) the closer your antenna is to the top & center of the vehicle, the better.
So the roof is better than the trunk and both of those are far better than
the bumper. But they'll all work.
2) a drilled/permanent mount is better than a magnet mount in the same loca-
tion. (This is so that the antenna gets a better "ground plane".) If you use
a magnet mount, run your coax feed line through the door or hatch that gets
the least use and then leave it alone. Don't use any path where the coax
would get pinched.
For base installations (i.e. at home) the best places are "as high as you can"
within legal limits. The roof is normally fine. If you're in an apartment
complex, you may be limited to a balcony but ask the manager - they may just
want you to keep it "invisible." (Check your national and local regulations.
In the US, the FCC regulations limit CB antennas to 60 feet above ground
level.)
Base station antennas should have a good ground in case of lightning. (In the
rare event of a lightning strike, this can mean the difference between burning
down the building or just the radio.) Most cold water pipes that go into the
ground will work. But the best choice for a ground would be an 8-foot (2.4m)
copper rod stuck in the ground near the antenna. (If you want to use anything
other than the rod for a ground, contact someone knowledgeable about housing
construction and safety - you don't want to accidentally use a hot water or
gas pipe. You also need to know your local building codes.)
* Once I hook up my CB and antenna, is the radio ready to use?
--------------------------------------------------------------
No. When you get a new CB and/or new antenna, the CB and the antenna must be
tuned or "matched." To do this, you need an SWR meter which is a device that
measures the impedance between the radio and the antenna. SWR stands for
"Standing Wave Ratio." The lower your SWR, the better your match. First
timers are recommended to get help from a knowledgeable person but some notes
about the process are included here.
You do NOT want your SWR reading to be over 3:1 ratio on any channel. It can
damage your radio. A "perfect" match is 1.0:1 which gives you the best
efficiency for your radio's output. However, "perfect" isn't possible so 1.1:1
is the best you can hope for. Even 1.5:1 is acceptable, but it isn't as good.
You will only be able to achieve your best match on one or a small group of
channels. The SWR will increase on each channel as you get further from that
point. So 2:1 may even be unavoidable on the extremes, like Channels 1 and/or
40. If you know you're going to use one channel most of the time, try to
put your best match there. Otherwise, just center it at Channel 20 so you
can use all 40 channels optimally.
You may find SWR meters at places like Radio Shack or amateur radio dealers.
Further information about Standing Wave Ratio can be obtained from the ARRL
Handbook. (ARRL is the Americal Radio Relay League. Their annual handbook
is full of information on many different aspects of amateur radio but the
basic concepts apply in all radio bands.)
Most stores that sell CB radios will have an SWR meter and someone who knows
how to use it. But they will charge for their services.
* What are good antenna characteristics and what are some good antennas?
------------------------------------------------------------------------
Antennas have to be designed to transmit and receive on the band that you
are using. CB is located in the 11-meter band. (They call it that because
the wavelength is about 11 meters.) CB antennas range in height from a little
under 2 feet (24 inches) up to 108 inches.
The 1/4 wave whip (108") will offer better reception and transmission
capability over a shorter, coiled or "loaded" antenna.
VERY short antennas, or multiple antennas that aren't "phased" properly
will result in a very poor signal. Remember, for cophasing antennas,
they must be 1/4 wavelength apart which, for the 11 meter band, is around
9 feet. Most cars aren't wide enough to allow antennas to be placed 9 feet
apart. The other characteristic of cophasing is that it is much more direc-
tional than a single antenna. It will transmit and receive MUCH better along
the axis of the car than sideways off the car so if you want a omnidirectional
antenna, you don't want cophasing (so you only want one antenna.)
Another subject of common questions is about antennas which receive AM/FM
broadcast stations and act as a CB transceiver antenna. User experiences
on this newsgroup vary widely with each brand. (The motorized ones seem to
have the least favor among the postings we've seen.) In general, these
antennas work but are not nearly as good as a dedicated CB antenna. You have
to weigh the advantages and disadvantages for your circumstances.
Good brands of dedicated CB antennas include (but are not necessarily limited
to) Hustler, Wilson, FireStick and K-40.
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