What is CB radio?
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CB radio is a public radio service, open to the use of any member of the general public.
No monthly bills, call charges or text messages to budget for - just pick up a microphone and speak - CB Radio can give you cheap and easy-to-use two-way radio communications.
With a vehicle-to-vehicle range of up to 5 miles and vehicle-to-base or base-to-base range of up to (and over) 10 miles, and nothing like the number of other users as there used to be - CB radio is the ideal farm communication tool. (Local terrain, weather and equipment used will all affect the range, but these are the sort of ranges you could expect while still maintaining a reasonably clear signal).
There are two types of CB set - "mobile" ones to use in a vehicle and "handheld" walkie-talkie types you can carry around with you or clip on your belt.
The mobile sets range in size from about the size of a thick paperback book, to something about the size of a Yellow Pages directory. They are supplied with a mounting bracket, a fist (hand held) microphone on a tough, curly lead, a red & black power lead for connection to the battery or fusebox and a users instruction manual.
There used to be 240v base station CB units, but these are no longer made - in order to set up a system at base, you need a mobile CB and a power supply which turns mains 240vAC into 12vDC (13.8v) so the CB can be used at base.
The handheld CB's are a little larger than mobile phones and run on AA size batteries and have their own aerial. Using rechargeable batteries will save a lot of money if you intend to use a handheld a lot - you can often charge the batteries within the unit so you don't have to constantly take them in and out.
You can use a handheld CB in a vehicle or machine, but the metalwork around you will reduce the range severely. To get round this, there are attachments for the handhelds that slide onto the bottom of the unit, in place of the battery compartment (making the unit a bit smaller), and have a cigar lighter plug with lead for power connection, and an external antenna socket for connecting to a standard roof mounted aerial. Using a handheld in this way will give it the same range as a conventional vehicle-fitted CB.
The main advantage with the hand-held types is that there is a large number of remote microphone/speakers available. There are earphones with small boom mics, clip-on mics, crash helmet sets, combined speaker/mics and even ones that go around your neck and pick up vibrations in your vocal chords - allowing use in very noisy environments.
All these can be made to automatically transmit when you start talking, giving you truly hands-free communications. Having said this, for purely machine or vehicle use, i.e. in a tractor, the conventional units are probably going to be easier to use over a period of time.
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What can CB do for you?
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The benefits of CB radio as a communications tool for farm workers, managers and owners are many...
Co-ordinate multi-vehicle operations easily - what is said by one person is heard by everyone else on the same channel, allowing control by one and feedback from others... productivity of workers can be vastly improved when they all have an easy way to talk to each other.
Increase safety for lone workers - have instant communication back-to-base or with colleagues and other people/machines in the vicinity - contact with co-workers is as easy as grabbing the microphone and saying “hello”. This can be very effective at combating boredom and isolation for lone operators.
This radio contact doesn’t stop at your boundaries and, depending on terrain and the types of aerials used, a base-to-vehicle range of over 10 miles is achievable, and convoys or groups of vehicles out on the road can keep in touch with each other, warning of obstacles ahead - road works & restrictions, passing route information and organising stops & loading/unloading arrangements.
There are still thousands of commercial vehicle drivers who still rely on CB everyday for traffic reports and directions in unfamiliar towns. On the motorway network - just asking for a traffic report on the calling channel (19, UK band) will usually get you information that is just seconds old. There may also be people from the area who can help you with shortcuts or other motorway drivers who can help with alternative routes.
In my experience, another by-product of kitting a farm fleet out with CB is the increased social contact between colleagues – banter and conversation, leading to higher staff morale. This in itself will usually bring it’s own productivity benefits.
Contact between neighbouring farms, groups of social friends or families is easy with CB - ideal for close communities, you can all chat together without any cost.
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What's involved?
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The actual equipment needed for a CB system is very simple - you need the CB itself, power for it (usually 12-14v) and an aerial. If you have a 24v vehicle, voltage droppers are available - these change 24v to 12v to allow you to run a CB and/or car stereo and other 12v equipment.
The aerial is really the most important part of any system - it makes all the difference to the range you will be likely to get. As a general rule-of-thumb, the larger an aerial is, the better it will work. It should be mounted so that it is not next to any object, and has clear space around it - ideally being the highest thing on the vehicle.
Vehicle Systems We deal with the installation of a conventional vehicle-mount CB in the “Installation Advice” section of this site Click here to view, which is largely just as applicable for tractors and other machinery, as well as normal cars, vans and lorries.
Modern farm machinery can present a few complications, but these can easily be overcome.
Firstly, the aerial needs to have a “ground” i.e. a part of the aerial mount will be designed to make metal-to-metal connection with the vehicle it’s fitted to. This can be difficult when cabs are made of fibreglass or composite materials, there is little metal to make this connection with.
You can get around this by using an artificial ground (Electronic Ground Plane - click here to view this product) which does-away with the need for a metal to metal connection. This means that a hole or bracket on a fibreglass cab will work fine as an aerial mounting.
The most common ways of mounting an aerial on a tractor are a “mirror mount” clamped onto the mirror arms, a “through hole” mount in the cab roof or another flat surface (although angle-adaptors are available), or a gutter mount if you have conventional gutters around the roof of the cab. If you have a metal cab roof or another flat metal surface, you could use a magnetic mount. As long as you have a decent quality mag mount, and use a flexible aerial, it should stay on fine even when hit by branches etc.
The second area of complication can be with interference. Although the CB’s have internal filtering, the sheer amount of electronics, pumps, fans and power-take-off equipment in modern machines can present problems.
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Curing Interference
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There are a number of ways to tackle interference, these are a good start...
You can prevent interference by taking the power supply for the CB straight from the battery, rather than from an accessory socket or the fusebox. This can avoid some of the crackles & whines that the machines electrical loom can pick up, as well as allowing you to use the CB whether the ignition or engine is on or not.) We can also supply an interference filter that goes in the red and black power lead between CB and battery - it is a simple small black box designed for bulkhead mounting, with two wires in and two wires out. Another way is to use aerial (coaxial) cable for the power feed, instead of the standard black & red cable. You can pass the positive up the middle, with the negative up the braid, or even better, use two lengths, and just use the centre conductor. (We can supply our coax cable in red and black colours to aid identification).
The electronic ground plane mentioned above can also help as this allows you to isolate the aerial from the vehicle which will reduce interference.
When you are choosing a place to mount the CB set, try moving the set around the inside of the cab when it is switched on and hissing but without any aerial connected. This might enable you to identify any interference "hotspots" that you should avoid. It often seems to be the way that the nice convenient panel that you would like to mount the CB in has a whole lot of "noisy" electronics an inch behind it!
Placing a CB in the roof can be a good place, although if you have air-con systems up there, it might pay to do the above check - just in case there is noise coming from the air-con unit.
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Using CB at base
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Often, the key to a farm fleet kitted out with CB is the use of a base station in the main buildings, workshop or office.
Using a large base aerial can increase the range of mobile CB's back-to-base to 10 miles or more - allowing you to co-ordinate local deliveries or tasks and liasing with nearby farms and workers.
There is only one 240v mains CB set made now, but any of the vehicle sets can easily be made to work as a base, by using a "power supply" which steps down 240v to 13.8v for the CB to use.
There are a number of base aerials available and we also supply brackets and fixings for these.
We have given Base CB a separate section in the Advice Pages, Click here to view it
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Alternatives to CB Radio
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There is nothing that really gives the range, effectiveness or affordability of CB radio, but there are a few alternatives...
Mobile Phones Although the costs of running mobile phones have dropped with tariffs that offer inclusive minutes or text messages, you still have the monthly charges, you can only speak to one person at a time and you are at the mercy of network coverage. It still makes sense to carry a phone, but... using CB for general communications will save you money and be more effective. Although CB’s also transmit radio waves, they are in a completely different part of the radio spectrum to mobile phones and there are no health concerns associated with CB signals.
Professional Radio This can be a way of getting a preset private (as much as un-scrambled radio can be) channel for radio communications, however this can be a very expensive way of doing it, possibly running into thousands of pounds a year (£150 a year for the licence alone). We can advise on and supply this equipment if necessary, but for the vast majority of people, CB will do effectively the same job for less money and with fewer complications.
PMR446 Radio This is a fairly new allocation for short-range communications using hand-held units only. Being on UHF (446 MHz, as opposed to CB on 27 MHz) it is not compatible with CB sets - CB’s and PMR446’s cannot talk to each other. This service has some advantages over CB, but also some disadvantages...
We have given PMR446 a separate section within these pages Click here to view this
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