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What is CB radio?
The origins of cb radio are lost in
the history of American truckers, the open highway, films like 'Smokey &
the Bandit' & Convoy. As far as we are concerned, its a 2 way radio
(no, not a walkie talkie!") system for telling the bloke in the Land
Rover in front that you are 1) Stuck, 2) in need of petrol, 3) Have a perfect
photo of him sliding into that last tree.
Why not just use a phone?
A phone is a 1 to 1 tool, with a
CB, everyone in your group will be able to hear you, & what's more,
there are no call charges, and you no longer require a licence.
What's the Range like
On a really good setup, with a top notch aerial & a booster
, anything up to 1000 miles.
With the sort of thing we're going to use probably more like 2 - 10 miles
depending on terrain & where the aerial is mounted etc.
Where do I get one?
In the old days, there was a CB shop on every High Street,
but not any more.
Now you are restricted to the few CB shops that still remain, car boot sales
& of course, ebay.
Shop wise, I would recommend Truck
King in Letchworth. He has been around since the 70's & his prices are
fair.
Internet wise, 4x4cb have a very
good site, with load of info & plenty of stock. When buying from car
boots, expect to pay no more than £5 as the chances are it doesn't work. When
it comes to ebay, even the nastiest untested stuff seems to fetch around £10,
so I wouldn't bother with 2nd hand, although there are some ebay sellers selling
new Midland radios at good prices.
What sort do I need?
Now it gets complicated. If you're not sure - Ask
1st.
To start with, every(*) UK CB radio will carry 1 of the following markings CB
27/81
PR 27/GB
PR 27/94
PR 27/97 For Use in UK Only Anything carrying the PR27/97 is dual band
& can communicate with any of the previous 3. To make things easy, we'll
put them in 2 piles
cb27/81
PR27/GB
PR27/94
PR27/97
PR27/97
So if you have a PR27GB, chances are , you wont be able to
speak to anyone in the club.
Most club members use old cb27/81 radios dating back to the early 80's &
still going strong
*Just to confuse things, some of the newer radios carry no
marking at all, & can cover just about every band at the push of a button,
but as they tend to be only available from shops who should be able to advise
you, I wont go into them here.
What's the best one to get?
I would always recommend the Midland 38.
It is bog basic, with no extra bells or whistles, but it does everything
we need it to. Expect to pay somewhere around £50 for a new one from a
reputable supplier.
For anyone who likes buttons & flashing lights, anything higher spec
from the Midland range (Midland
98 & 78) are also good radios.
Don't be surprised if you see Midland radios badged as Kernow, but note,
they will be old stock.
The Rolls Royce in my book is the Cobra 25
or 29 Nightwatch. More features than you can shake a stick at, &
a really pretty illuminated display to boot, but way over the top for
what we need.
I would avoid anything 2nd hand unless you know
the seller.
Aerials
Too many to go into now, & they depend on where they're going to be
mounted, & what your intended use is.
Have a look at 4x4cb
advice pages, or have a chat with someone in the club
Fitting
I always try to mount the radio away from any source of electrical interference.
Ideally run in a new 5a fused power lead direct from the battery.
Be very careful with your + & -. Get it wrong & you will have a £50
paperweight.
Try to mount the unit so that the speaker is not pointing straight into the
carpet unless you use an external speaker. Mobile phone speakers are ideal
& can be had from ebay for a few £'s.
Always check aerial cables with a multi meter to ensure there is no short
between the inner & outer core (paperweight time again).
Ensure the centre core of the cable is making good connection to the whip.
Ensure the outer core is making a perfect electrical connection to the body of
the vehicle.
Try to mount the aerial so that it is in 'free air'. The ideal place is smack
in the middle of the roof (or roofrack). Anything else is a compromise BUT
Greenlaners beware, trees will rip aerials out in seconds, so for those of you
who like forcing their way thru the undergrowth you will have to try to mount
it as best you can. 4x4 cb
has some good advice for types of aerial mountings.
SWR
what?
No, I cant remember what it stands for either, but it is very important.
You have now installed the radio, fitted the aerial, checked all the
connections for shorts etc, so you're ready to go, right?
WRONG.
You need to check your SWR. This is done with a SWR
meter Unless you have one kicking around, I wouldn't bother
buying one, you'll always be able to borrow one for the installation,
& ideally every few months just to check.
A SWR meter checks how much of the transmitted radio signal is coming back
down into the radio. Ideally it should be very low. a SWR of greater than 2 is
something to be avoided. Greater than 3 & it's paperweight time yet again.
Confused?
Dont be.
It may sound like you need a degree in electronic engineering, but its
not that bad really. Most important thing to remember is that there are
many of us in the club who have all the test
kit as well as a rough idea how to use it, so make sure you ask someone.
If
you do need any help, drop me an email, or
collar me at the pub or wherever & I'll see what I can do.
For some very useful tips & answers to some of the more
common installation problems, see this site http://www.firestik.com/Tech_Docs.htm
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Thanks to Peter Brackenbury for suggesting it.
UPDATE: 12/8/2006: From Tim Smith.
RE: Truck King in Letchworth.
I have just been there today to get a few bits and it has been taken
over by www.rocketradio.net in
the same unit.
Truck king has moved out of this area and is only doing internet sales.
(Rocket radio were just as helpful as the previous owner. I would go
back)
Shame, Tuck King has been around for years. Rocket Radio have been trading
on Ebay for a number of years. I've had some stuff off them in the past
& they have always seemed ok to me as well. - Mark
NOTE: Rocket
Radio are now offering a 5% discount to all our members on
production of a valid membership card
By the way - Unless you drive an orange Charger with a
horn that plays dixie.
It is Not mandatory to speak in an American accent.
You will Not be required to memorise the '10' codes.
Anyone using the phrase '10-4 Good buddy' will get the mick taken endlessly.
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