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 CB (Citizen's Band) Radio Answers

Question: Do I need a licence to use a CB radio?

Answer:
No. In the early 1980's, the FCC stopped requiring licenses for CB radio use. However, users must still abide by the FCC rules regarding the CB Band.

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Question: What are the CB frequencies?

Answer:
The 40 CB channels are as follows:
1) 26.965 MHz 9) 27.065 MHz 17) 27.165 MHz 25) 27.245 MHz 33) 27.335 MHz
2) 26.975 MHz 10) 27.075 MHz 18) 27.175 MHz 26) 27.265 MHz 34) 27.345 MHz
3) 26.985 MHz 11) 27.085 MHz 19) 27.185 MHz 27) 27.275 MHz 35) 27.355 MHz
4) 27.005 MHz 12) 27.105 MHz 20) 27.205 MHz 28) 27.285 MHz 36) 27.365 MHz
5) 27.015 MHz 13) 27.115 MHz 21) 27.215 MHz 29) 27.295 MHz 37) 27.375 MHz
6) 27.025 MHz 14) 27.125 MHz 22) 27.225 MHz 30) 27.305 MHz 38) 27.385 MHz
7) 27.035 MHz 15) 27.135 MHz 23) 27.255 MHz 31) 27.315 MHz 39) 27.395 MHz
8) 27.055 MHz 16) 27.155 MHz 24) 27.235 MHz 32) 27.325 MHz 40) 27.405 MHz

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Question: What is the range of my CB?

Answer:
At full legal-power, CB's have a maximum range of up to 4 miles. However, due to interference and/or obstacles, it is not possible to determine exact range for a certain area; range will vary regardless of the type, model or manufacturer of radio used.

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Question: Is there any license I can get or buy that will allow extra CB channels or higher power?

Answer:
No. CB radios in the United States have the following restrictions: operate only on the 40 26-27 Mhz CB channels, they must be FCC approved for CB use, and have 4w AM/12W pep SSB maximum output power, license free. There is no commercial license or ham license that allows the user to run higher power, use extra channels or use modified amateur rigs in the 11M 26/27Mhz CB radio band.

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Question: Can I use my CB in my business?

Answer:
There are no restrictions on using a CB radio to aid in the operation of your business.

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Question: Is Channel 9 an official emergency channel?

Answer:
CB channel 9 has been designated by the FCC as an emergency contact channel. However, this designation is only valid in the United States and other countries do not have this "official" designation for the channel, so it would not be uncommon to hear stations conducting non-emergency radio traffic on this channel when skip is in. There are stations across the country, including many police and rescue agencies that actively monitor this channel for those who have a problem ranging from medical emergencies, accidents, vehicle breakdowns, to being lost.

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Question: Is Channel 19 an official channel like Channel 9?

Answer:
Channel 19 is an "unofficial" trucker's channel. The FCC has not designated this as an "official" trucker's channel; however, truckers are about all you will hear on this channel. When traveling this is a good channel to monitor in order to keep up on traffic jams, accidents and traffic enforcement.

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Question: What are the 10-codes?

Answer:
The basic 10 codes are listed in all of our Citizen Band Radios manuals; they are as follows:
Code Meaning Code Meaning
10-1 Cannot understand your message. 10-16 Reply to message.
10-2 Your signal is good. 10-17 En route.
10-3 Stop transmitting. 10-18 Urgent.
10-4 Message received and understood. 10-19 Contact __________
10-5 Relay information to ___________. 10-20 What is your location?
10-6 I am busy or are you busy? 10-21 Call __________ by telephone.
10-7 Out of service. 10-22 Cancel last message.
10-8 In service. 10-23 Arrived at the scene.
10-9 Repeat last message. 10-24 Assignment complete.
10-10 Negative (No). 10-25 Meet __________
10-11 __________ in service. 10-26 Estimated time of arrival is __________
10-12 Stand by. 10-30 Use caution.
10-13 Report __________ conditions. 10-31 Pick up.
10-14 Information. 10-33 Emergency traffic. Clear the channel.
10-15 Message delivered. 10-34 What time is it?

You can get further information on specialized codes used by local emergency agencies, through the Police Call Handbook for your area, by contacting your local Ham or Scanner club or by contacting the agency directly.

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Question: Is there a CB made with a built-in police radio scanner?

Answer:
No. While some scanners will receive the 40 CB channels, none will transmit.

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Question: What is sideband?

Answer:
Sideband, also known as single sideband (SSB), is a more effective use of the existing channels on a CB radio. By operating on a narrower band, the effective range is increased; however,.the signal does not sound as clear as an AM signal. When using sideband, you should also use the clairifier in order to clear up the sound of the transmission.

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Question: What is the roger beep?

Answer:
The roger beep is a short duration single-tone or multi-tone signal that is sent when you unkey your mike. This was originally intended to give a true confirmation to the receiving station of when the other person was finished talking, especially during weak signal and SSB reception.

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Question: What does the squelch do?

Answer:
The squelch quiets the background radio noise (static) when there is no signal present.

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Question: What type of antenna do I need?

Answer:
That depends on which type of installation you are going to be using. A home installation can use two types of antennas -- omindirectional and beam. The omnidirectional antenna sends and receives signals with equal strength in all directions (360 degrees). A beam antenna will concentrate the signal in a particular direction. This will give you better range in whatever direction you have the beam pointed. The disadvantage is that it will be necessary to "rotate" the beam in the direction of the station you are trying to contact.

There are a number of different types and styles of antennas for mobile installations, including magnetic mounts, gutter lip mounts, trunk lip mounts, mirror mounts and permanent mounts. Each type has advantages and disadvantages.

When comparing antennas, you should select the largest antenna with the highest gain that will meet your installation needs.

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Question: What is the best antenna for my mobile CB radio?

Answer:
This is tough to answer, but here are some good general guidelines and "Rules of thumb". First, The Taller the antenna, the better it will work. Mount your antenna as high as possible on the vehicle, and try to get at least 50% of it over the roofline. Usually, all else being equal, the Tallest, longest antenna you are comfortable with, mounted as high as possible, will give the best performance. For Example, mounting a new 4 ft CB antenna where you had a 2 footer, will usually give better results. It wouldn't matter what "brand name", color or style the 2 ft antenna was. CB antennas that are less than 3 feet tall, those that "stick to the glass", and AM/FM/CB "combo" antennas and adaptors generally do not give good performance, they are bought and sold mainly for "convienience" and "cosmetic" reasons.

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Question: Where should I mount my antenna?

Answer:
The best place to mount the antenna is in the center of the roof of the vehicle. If that is not feasible, then the antenna should be mounted in the center of the trunk. Mounting the antenna in other locations on the vehicle will tend to make it directional (much like a beam) rather than unidirectional.

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Question: What is a groundplane?

Answer:
Most mobile antennas are actually only half of the effective antenna, the other half is the body of the car or truck. This "other half" is also known as the Ground Plane of the antenna. If the Groundplane isn't adequate or large enough, poor SWR readings and performance will result.

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Question: What antennas should I use on a fiberglass or non-metallic surface?

Answer:
You would need to use a special "No Ground Needed" antenna, such as are designed for boats and other non-metallic surfaces.

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Question: What is the gain for a particular CB antenna? What antenna has the best gain?

Answer:
Gain can be measured either against a 1/4-wave antenna or 1/2-wave. For most antennas, the old industry standard was to compare antenna gain to an isotropic antenna, which is a theoretical antenna that has the gain of a 1/2-wave antenna, but all emissions emanate from a pinpoint (that's why it's only theoretical). An isotropic antenna can be loosely defined as a single half-wave element. CB radio frequencies center around 27.2 MHz. By today's standards, that's a low frequency, even though back when it was named, it was called the "HF" or High Frequency band. The lower the frequency, the LONGER the wavelength. The longer the wavelength, the longer the antenna needs to be to have any gain. There is a commonly used formula to calculate the starting wire length for a 1/2 wavelength wire antenna:

Length = 468/Freq

Length is in feet, and Freq is in MHz. For CB, we solve this as follows: length = 468/27.2 = 17 feet, 2-1/2 inches. So, we now know that an antenna of about 17 feet will have the same gain (zero gain) when compared to a 1/2-wavelength antenna.

Over the years, antenna manufacturers played a specification game with each one trying to show their antennas were better, and eventually someone started comparing to a 1/4-wave whip instead of the isotropic. Since a 1/4-wave has only half the gain of an isotropic antenna, they were able to advertise twice the gain. However, the antennas themselves didn't get better - only the advertised gain number changed. It's important when you see a gain specification to find out what the standard reference antenna was.

In CB, the standard reference antenna is a 102" whip. Since all mobile antennas (except the 102" whip, of course) are shorter than 1/4-wave, performance will NOT be as good as the 102" whip. So, no one in the industry has ever published gain specs for mobile CB antennas - since they would ALL look bad!

Even heavily advertised branded antennas compare their antennas to other comparable antennas. You may notice that they are not compared to a 102" whip, and it's easy to understand why. These expensive antennas are not as good as the simple, inexpensive 102" quarter-wave whip antennas.

We suggest that you purchase the largest CB antenna that is practical for your vehicle. You should consider whether your vehicle needs to get in and out of a garage, and where the antenna will mount in order to make a good decision. All claims aside, in mobile CB antennas, there's just no compromise for length!

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Question: What is the impedance for a particular CB antenna?

Answer:
All of our CB antennas have roughly 50 Ohm impedance to match the output of the CB radio. The impedance is not critical as 25 Ohms to 100 Ohms is acceptable; however, the best signal transfer occurs at 50 Ohms, so every design is optimized very close to 50 Ohms.

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Question: How do I increase the transmit power of my CB?

Answer:
The maximum legal input power for a CB radio is 5 watts, which provides a power output of about 4 watts. Using any device to increase power above this point is illegal. Overpowered CB radios often cause interference to electronic appliances such as TV;s, VCR;s, stereos, and even telephones. People experiencing such problems can file a complaint against the offender with the FCC.

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Question: If I want to use a mobile CB as a home base station, what will I need?

Answer:
You would need a good base station CB antenna and a regulated power supply to convert the 120V AC power to 13.8V DC power. You will need to select a power supply that provides at least as many amps as your radio requires.

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Question: What's a power mike?

Answer:
Power microphones are replacement microphones for a CB radio that require a battery, and are amplified. They do not give the radio more power.

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Question: What is a noise cancelling mike?

Answer:
This is a microphone designed to reject more backround noise and only pick up the user's voice close to the microphone.

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Question: I get noise on my radio when I connect it in my vehicle; how do I troubleshoot it?

Answer:
see Troubleshooting.

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Question: Why do I get continuity between the whip portion and the center of my CB antenna, and between the whip and shield portion, but not between the center and the shield?

Answer:
see Troubleshooting.

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