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 How great would it be to use CB on the move, or have a CB radio in your car, van or truck? Great? Yes, really great! It's really easy too. There are essentially two choices for using CB on the move; Hand-Held CB Radios and the more commonly found Mobile CB Radios. BigCat says: Don't hog the One Nine! - Channel 19 is not for general conversations.
Move off channel 19 a.s.a.p. & keep the calling channel clear for other breakers ! Hand Held "Walkie Talkies"
How to set up your Mobile CB Radio in a vehicle. In it's simplest form all you need is a CB radio, antenna and suitable antenna mount with connecting cable:
Additionally you will need a few extra small items - a suitable power connector, an "SWR" meter and a short PL259 to PL259 50 ohm "patch lead". See SWR & Antennas & CB Accessories When choosing a new CB rig be sure to visit one of the highly valued specialist CB retailers that can be found on the CB Links Page.
The choice of new radios is very large and prices vary from about £50 to well over £100. It is well worth bearing in mind that no matter what the price of a new radio they all have a transmitter power of 4 watts. 4 watts is the legal maximum, so an expensive rig will transmit no further than a cheaper one! To gain greater range it is wise to spend more on a larger and better antenna than a more expensive radio. More expensive CB radios do tend to have more comprehensive facilities and are usually better finished with a higher build quality. When buying a radio it is very important to ensure that it covers both to 40 UK (27/81) channels AND the 40 EU (CEPT) channels. That's essentially 80 channels. The latest CB radios are extremely clever and are specially programmed to be able to be set for use in individual European countries where different regulations apply - this takes account of differing channel sets, transmissions modes and output powers, this is called 'multi-region' capability, so look out for Multi-Region capable radios. Look out for brands such as Midland Alan, President, Intek, Team, tti, and Danita for example. See our Links page here. There are always a number of CB radios on the second hand market, particularly the auction sites such as e-bay, but many of these have only half the number of channels that you need - namely the 40 UK channels. Personally I would NEVER buy a second hand CB radio - EVER! Many CB radio enthusiasts often like to make all sorts modifications to the internal electronic circuits, and you will never be sure that a second hand CB will be working properly. Only the day before writing this page, I was talking on the CB to a breaker who proudly announced that he had just bought a second hand CB. He then connected it to his antenna and power supply and keyed the microphone. I heard him talk for about 20 seconds before his voice disappeared and the rig appeared to be permanently keyed up on the channel with no modulation. He then had to disconnect the CB and returned to the air with the original rig. Apparently some of the circuitry had been tampered with inside, so now he has the problem of trying to fix the problem himself or pay for a repair. That's just one of many examples so be warned! CONTROLS & FACILITIES: A CB radio needs only a minimal number of controls to be fully functional, although some rigs include many more. The basic and essential controls are On/Off, Volume, Channel Change, Band Change and Squelch. A basic CB radio will probably be more than adequate for most newcomers, though there's no reason why one should not choose a more complex radio, but bear in mind that it is more important to concentrate on buying the biggest and best antenna possible than the most complex radio. The more expensive radios might include a number of other controls which may or may not be of particular importance to individual users. These may include adjustable microphone gain, adjustable RF gain, memories, channel scan, dual watch, last channel recall, noise limiter or processor, PA, key lock, frequency display, quick up & down buttons. See the table below for more details:
 Midland Alan 48 Excel Multi - mobile CB Transceiver Most CB radios will also include a Signal Meter that will give an indication of the received signal strength - referred to in CB parlance as 'Poundage'. Bear in mind that not even the signal meters on the most expensive radios are accurate or properly calibrated, and can only give a visual representation of relative signal strengths. Most modern CBs have a signal meter in the form of an LED bar-graph (like a mobile phone) but others have a more traditional 'swinging needle' analogue meter that many CB operators prefer since it looks like rigs of old and can show infinite movements in signal strength.
Signal meters have scales marked S1 - S9. S1 being the weakest signal and S9 being strong signals. S9 represents a received signal of, (arguably), 50 microvolts. There are additional markings above S9, usually marked +30 on CB radios, which means a voltage of 30 decibels above 50 microvolts which is 1580 microvolts. Many S meters also double as a very rudimentary power meter to provide an indication of the power output when transmitting (TX). See more about "S" Meters Here > When choosing a new radio be sure to visit one of the highly valued specialist CB retailers that can be found on the CB Links Page. Mounting The Rig In The Vehicle All new CB rigs are supplied with some essential accessories that you will need to get going; the all important instruction manual, the microphone, a microphone hanger (bracket), the power lead and rig bracket with screws.
Power for a standard 4 watt mobile CB can most easily be taken from the cigar lighter socket since it would only draw about 2 amps. The CB power cable would have to be fitted with the correct plug. The CB must be fitted with a 5 amp fuse in-line. This is the method that I use and I find it to be very convenient. For a more permanent install, or for when more current might be required, the radio could be wired directly to the vehicle's electrical supply via a 5 amp fuse. This method is neater and may be more reliable than the cigar lighter option, but should only be done on a DIY basis if you are familiar with vehicle electrics, otherwise engage a qualified vehicle electrician to make these connections.
In the world of CB radio bigger really is better! The longer the antenna the better the reception will be and the further your signal will carry. however the length of any antenna must also be of an electrically correct length - tuned to be resonant at the frequency being used.In simplest terms, the idea is to get an antenna as near to the size of the wavelength of the radio wave that is possible. This will provide the best signals. CB uses radio frequencies of around 27 MHz which have wavelengths of around 11 meters (300 divided by 27 = 11.1m) An antenna that is 11 meters long is obviously far too long to mount onto a moving vehicle! However one of the most popular and effective aerials used for 'Home Base' operation is a 1/2 wave antenna - but that's still 5.5 meters long! Still far too long to mount onto a car, van or truck. Another popular antenna is the 1/4 wave type but even that, at 2.75 meters, is still too long for mobile use. To overcome this problem antenna manufacturers will include a 'loading coil', sometimes at the top or centre of the antenna whip, but more usually at the base. The loading coil enables the overall length of the whip to be reduced to much more manageable lengths. Loading does come at a price though due to loss of efficiency - shorter antennas will not work as well as longer 1/4 wave antennas, but as long as the antenna is not too short, the range achieved should still be acceptable for local communication. It's probably best not to use an antenna much shorter than 1 meter. The most popular antennas tend to be around 1.5 or 1.6 meters, but many prefer to use as long an antenna as possible which may mean lengths of 1.8m to 2.0m. My personal favourites are the antennas marketed by Thunderpole, they represent extremely good value for money and provide really good performance. Look out for the Thunderpole 'Red Devil', 'Voyager', 'Orbitor', 'Atom' and 'Trucker 80'. For those looking for long distance (DX) contacts the Thunderpole 'Red Devil' is a good choice, but the Sirio Hi-Power 4000 and Sirio Megawatt 4000 are also popular, but more expensive, alternatives. For static mobile work (i.e. parked and stationary) the very long 1/4 wave Sharmans "Tank Whip" from Rocket Radio is a good choice.
How the position of the antenna changes the radiation pattern of the transmitted signal:
One of the most popular types of mount is the "Mag Mount" because it is so easy to fit and remove when not needed. The mag mount is placed in a central position on the roof and the coaxial cable routed into the vehicle via a passenger, rear door or hatchback jamb There are many other types of antenna mount available for more permanent installations on a boot lid, hatch back, bumper, through the body or for fixing to a truck mirror bracket for example. The cable would then be routed through the vehicle and concealed behind trim and carpet etc so that the installation was not visible. This method may involve having to drill holes - so a degree of competence when working with vehicles is needed. Where the coaxial cable does pass through holes, a protective rubber grommet is essential to prevent the cable being damaged - a damaged antenna cable would not only cause bad signals, it could badly damage the CB rig. It is advisable to seek specific advice from a specialist CB retailer. See the CB Links Page. Here is a selection of different vehicle mounts that are available from Thunderpole:
  Thunderpole Orbitor - 155cm long CB antenna on a Sirio 145 Mag Mount  Sharmans 1/4 Wave Tank Whip antenna from Rocket Radio. It's 275cm long & seen here on Sirio 145 Mag Mount  Intek M-790 Plus Multi - mobile CB transceiver  tti TCB-770 - mobile CB transceiver
 President Jackson II - mobile CB transceiver Remember in a time of national emergency the telephone networks could fail, CB radio could be your only point of contact with the outside world. More CB Radio information from Right Channel Radios USA |
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Mike Smith - MDS975.co.uk © 2003 - 2008