CB Radio For Beginners
A CB radio or (citizens band) radio is the perfect medium range communications tool. The average store bought 2 way radio usually operates on GRMS or FRS frequencies. These frequencies are limited to a few miles and are limited already further by buildings, tress, mountains and all obstacles. CB radios can acquire ranges up to 150 miles, sometimes more. CB’s function on a different frequency than traditional consumer radios which allows them to acquire these extended ranges and makes them a preferable communications tools.
Radio groups are electro-magnetic groups that rely on antenna to cast their signal. Radios can oscillate at a certain frequency to receive or transmit these groups. Megahertz method millions of cycles per second, so when a signal is measured in say 500 megahertz it method that frequency is oscillating at 500 million times per second. As an example here are the shared frequencies used in the world.
o AM radio – 535 kilohertz to 1.7 megahertz
o Short wave radio – bands from 5.9 megahertz to 26.1 megahertz
o (CB) Citizens band radio – 26.96 megahertz to 27.41 megahertz
o TV stations – 54 to 88 megahertz for channels 2 by 6
o FM radio – 88 megahertz to 108 megahertz
o TV stations – 174 to 220 megahertz for channels 7 by 13
Antennas work best with their radios when the length of the antenna matches the wavelength being transmitted. CB radio begins at 25.01 megahertz meaning that the antenna would need to be just over 39 feet to match the wavelength. A simple way to measure is using this shared formula.
Wavelength (in feet) = 984 / frequency (in megahertz)
clearly 40 feet is a bit long for most cars or already houses for that matter so people tend to use antennas that are a fraction of their proper length such as 1/2, 1/4, 1/8 or 5/8ths.
There are approximately 40 channels in the CB spectrum but clearly it’s not possible to have an individual for each frequency. To compensate most antennas lie somewhere in the middle of the spectrum to access as many channels as possible. This does waste some strength as not all of the electricity is transmitted properly into radio frequencies.
Types of CB Radios
There are basically two types of CB radios; portable ones or stationary ones. The portable CB has a much smaller range due to a small antenna but operates wonderfully with a nearby Base stop which has a long range. Many opt to buy a base stop for use in the car since it has complete functionality and can be used with the antenna in their car or a separate antenna at home. Below are some examples of CB radios.
Base CB radio – Cobra 148 GTL
The 148 GTL is the best CB you can buy without spending a fortune. This CB utilizes sideband, a frequency in between the main frequencies, to give you not just the complete 40 channels but an additional 40 sideband channels. For privacy and performance this is the right radio.
Portable CB Radio – Cobra Compact/ far away Mount
This radio is an all in one CB with portability for every situation. This is a great example of modern technology mixing with the typical portable CB.
Some people believe that CB radios are limited to 50-300 miles, they are wrong. Although it’s technically illegal (in the US) many hobbyists choose to shoot their radio signals up into the ionosphere, which during heavy sunspot activity can reach areas across the world. Since shooting skip relies on the radiation from the sun, if there is limited sun identify activity it may not be possible to shoot skip at all. Likewise long periods of sun activity make it possible to talk to places around the world for long periods of time. The only exception to this is during mid summer when there is inconsistent sunspot activity, although it is highly unpredictable.