You would be amazed the amount of people who have not SWR'd their antenna in because they dont know how to use a SWR meter. It is one of the most
simplest accessories to use

Patch Lead from CB to Trans. Socket on back of meter
Antenna lead from Ant. Socket on back of meter

1/ If you are using a 40ch CB put it on channel 20. On your SWR meter
if it has a PWR/SWR setting put this to SWR and put the FWD/REF switch to FWD
2/ Depress the mic key and adjust the Knob/Slider on SWR meter so the needle
goes over to the "SET" part of the scale.
3/ Throw switch to REF and depress the mic key once more. The needle on REF
needs to move as little as possible. If it flies into the red re-check your
connections and make sure your plugs are correctly soldered and there
are no shorts or breaks in the CO-AX cable
4/ Adjust your antenna up or down slightly and TX again noting if the SWR reading is going higher or lower. You dont need to re-adjust your SWR meter while
doing this. Once you have calibrated it just TX to check if SWR is improving or worsening.
5/ When you have the SWR is at its lowest you can disconnect the SWR meter but re-check every month to make sure all is still well especially with magmount
antennas on vehicles.
Before we go into this there are a few points that need noting. One is that your
SWR has to be as low as you can get it, in any case lower than 1:5:1 as these will
burn out quite quickly with a bad SWR and could also damage the CB. Another is
that if you have a long feed to your antenna use RG8 or RG213 thicker type co-ax.
If your using a mobile linear as a homebase please make sure you have a large
enough PSU (power supply unit) to run it. (See PSU's)

This is connected in the same way as a SWR meter. This 50w linear must have a
power cable rating of 5A or above. To run this particular model you would need a PSU rated at
least 7A to 9A. Its a good idea to make sure your radio isn't pushing more than 4w into the linear
as more could damage the linear. IMPORTANT. These types of linear are intended for short bursts
only and not continuous transmission. If you decide your the next Chris Moyles and play music over
the CB  your equipment isn't going to last for long
This has proved the downfall of many a breaker trying to run a linear and a CB off their 3A PSU. Below is a rough "rule of
thumb" to what size PSU you are going to need ...

3 to 5A -
Standard CB radio, not a Sidebander.
5 to 7A - Standard CB radio and small accessories ie. Echo chambers
7 to 9A - Most un-tweaked SSB radios or a standard CB with a small linear. ie. 30w
10 to 14A -
Standard SSB radio tweaked or un-tweaked with a small linear and/or
         echo chamber or a standard CB with up to 100w linear
15 to 20A - Most things apart from the big boys.
20A+ - Pretty much anything you can think of. Nice to have but very expensive new.
Pre-amplifiers boost "incoming" signals increasing the "Just audible" signal to a reasonable level

A bit like having an RF gain control 1/2 way up then turning it up full. On FM
it doesn't make a huge difference but is more beneficial when on AM/SSB in
quiet conditions. Beware though that using one of these will also bring in any
"stray noise" louder too. Makes no difference to out-going signals and is
connected the same as a SWR meter but needs a 12v DC Supply. Some bigger
Linears have these built in too. BTW if you do have these separate put the
pre-amp first in line from the CB likewise the SWR meter second (or vice versa)
but dont run the linear before these. The linear wants to be last in line before the
Antenna unless your SWR meter can handle the power.
Remember, connect a busy system as follows,
CB - Pre-amp - SWR meter - Linear - Antenna
Or if high rated SWR meter,
CB pre-amp - Linear - Swr/Pwr meter - Antenna (Never use an antenna tuner when pushing power. Sort your SWR out properly)
A splitter box allows you to either run more than one antenna with your CB or
more than one CB with your antenna without having to fiddle about changing
co-ax leads over. Nice and simple but can be very useful.

The one shown will run two antennas or two CB's but you can get splitter
boxes with 3 or more options. Make sure the Cb is actually switched IN before
This does exactly as it says on the tin.... In most Trucks you will find the power for
accessories is rated at 24v.

If you attach a 12v CB to this it will go POP. The 24v is reduced to 12v through the
dropper so all is well. There are a few Linears and CB's out there rated at 24v but
these are in a minority so most truckers need a dropper. Don't go for less than a
10A one
Your CB may well have a CB/PA switch.
Now if you attach an extension speaker to this and throw the switch
to PA you can listen to the audio transmitted through the mic. All good
for testing to make sure your mic is working OK and for setting the level
on your echo mic but the real purpose of this is PA (Public Address)
If you fit a "PA" horn under your bonnet in your car you can "shout"
at people while driving down the road (highly illegal but fun)
You mentioned "Echo" ?

An echo power mic is similar to a normal mic but a bit bulkier
with sliders or wheels to adjust the loudness and echo levels.
If its a good echo mic it will have depth as well as repeat.
The correct setting is to have just a hint of echo on your outgoing
modulation. An echo mic can be hand held or a desk mic
Some people hate these, some love them... it's personal choice ..
Nice and simple this one.

On the back of your CB you will almost certainly find an
Ext.Spr. socket. if you want you can buy a separate speaker
which, normally, will give you a better sound than the CB's
internal speaker as it has no size constraints to worry about.
Also some come with fitted filters which you can switch to
give a clearer, crisper sound. Also good as mentioned above
to plug into your PA socket to check echo/mod from your mic
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CB Radio Repairers in the UK
CB Radio History from its early days