Communications

Prepping and survival is a solitary world.
Mostly we are scared of divulging our presence worried about what would happen in a crisis.

This is because people (sheeple) are basically horrible. In an emergency they will start to loot, steal, and attack anyone who has something they want and not necessarily what they need.
The change from friend to fiend can happen in hours.

So why bother communicating with anyone at all?
No matter what you feel, you may need to get help and it is unlikely to come from government sources especially if the rule of law collapses.

Consider traditional means of communications.

Telephones.
Possibly the most reliable in the short term. 
Phones are usually powered form the phone lines and the telephone exchanges contain battery backup systems. I’m not sure how long they last for when the mains die.

Mobile phones.
Highly dependent on mains power for their cell stations and high speed networks linking into the telephone system.

Radios.
The UK government disassembled the radio early warning and “emergency broadcast system” in 1994. 
We are now totally dependent on the BBC and local radio or television for information.  
Lose mains and we will lose most of our broadcast systems as soon as any battery back up systems fail.
So radios are limited for government or amateur use.
i.e. Marine Band, Air Band, Citizens Band (CB) and Amateur radio enthusiasts.

Both the government monitored systems will work indefinitely BUT whether or not you can call them for individual help is unclear.
The relevant frequencies I’ve already covered as with CB but I list them below.

Using a CB Radio To call for help
CB Channel 9 Emergency Traffic Only (unpredictable)

(27.68125 MHz) UK , (27.0650 MHz) CEPT / EU /US


CB Channel 19 UK Trucking Main Contact Channel 

Used for Alternative Emergency Calling (unpredictable)
(27.78125 MHz) UK , (27.1850 MHz) CEPT / EU / US

Note the average range for communications is typically less than 5 miles. This is well within reach by a person on foot. 

Marine Radio To call for help

VHF Channel 16 General Contact Channel / Emergency Calling (24 hours)

(156.8 MHz) UK

HF Emergency Calling (Watch kept hh00 to hh03 and hh30 to hh33)
(2182kHz) International

Digital Selective Calling (DCS) Channel 70 (24 hours)
(156.525 MHz) 

Air Band Radio 
(121.5MHz) For civilian communications (24 hours)
(243.0 MHz) UHF Military Communications (24 hours)

Most non hand held Radios need setting up.
The setting up consists of tuning the aerial to suit the frequency in use.
This process is called SWRing the aerial.
It is quite a simple process using an in line device called a SWR meter.
I have added the instructions for setting up a CB set.

Tuning An Aerial
When you connect an aerial to a transmitter (be it Ham, CB, or PMR) you need to make sure that it is working correctly.

To do this you need to adjust it’s length to “tune it in” to your radio.
To do this you’ll need to connect a test meter in line called a SWR Meter.

What is a SWR meter used for?
Simply put, a SWR meter compares the power that can be delivered by the CB to what is actually leaving the aerial.
By adjusting the length of the aerial you “tune it” to your CB rig.
Get it right, and the SWR will be 1:1 thus all the power goes out into space and the aerial is “tuned” to pick out incoming transmissions.
So more power out and better reception.

If something is not quite right i.e. things aren’t correctly fitted, worked loose, not tuned, or damaged, some of the power will be “reflected” back into the RADIO.

Too much “reflected” power can destroy the transmitter let alone affect your reception. A badly tuned aerial is rather like a badly tuned guitar string. Grating on the ears, makes loads of noise, and in radio terms causes loads of interference that can affect your neighbours TV & stereo.
Not a good thing.

So what’s good and bad levels of SWR?

1.5:1 to 1:1 is brilliant. 96-100% of your power hits the airways.
2.0:1 to 1.75:1 isn’t great. 89-93% of your power goes out
10:1 to 3.0 is disastrous. 33-75% is all that gets out.


Above 10, (needle flies to the right and stays there) you’ve got VERY serious problems. Either a lead or aerial is broken or you’ve got an electrical short.

Tuning Your Aerial To Your Rig

Read the little paper that came with the SWR meter to familiarize yourself with the switches (Forward / Reverse or FWD /REV), the scale, the control knob (CAL) to control the needle, and the connections on the back.

A Typical Set Up

Install everything into it’s correct place.
Once you have finished your installation, don’t move things round. SWR may change if you do.

About costs.
A cheapy little CB only SWR meter will set you back £9 – £15.
You’ll need a little patch lead which plugs into the back of the CB sets aerial socket and into the “IN” plug of the SWR meter. That costs £4 – £8.

Note: The aerial lead then goes into the “OUT” plug of the SWR meter.

Switch on the set and select LOW POWER until you have SWR’d the aerial.
Put the switch to “FWD” and transmit. Turn the CAL knob so that the needle swings over to the far right of the scale and align the needle with the set (or Cal) mark.

Still transmitting, switch over to “REV” (Reflected) and the needle should drop down. Note that reading.

CAUTION! If the needle hardly drops when you switch over, slams into the right hand side and stays there, or does not come out of the red portion of the scale STOP TRANSMITTING.Something is VERY WRONG.

Check the aerial plug is connected properly, and your coax and aerial for damage, or breaks.
Assuming that it did drop, you can happily carry on.

For UK Only Sets (40 channels Only)
Take readings on Ch. 1 and 40 and make a note of them.

On each test re-tune the needle to the set mark on FWD each time you change channel.
DON’T FORGET, EVERY TIME!!!

If the SWR is higher on Ch.1 than Ch. 40 Lengthen the aerial
If the SWR is Lower on Ch.1 than Ch. 40 Shorten the aerial
In this case you would slacken the grub screw in the aerial and SHORTEN the aerial.


Typically the readings shown above will balance round 1.3 to 1.5 at both ends.

And finally
Some leave the SWR meter in line after tuning. You can if you want BUT you can also take it out and then it’s one less thing to worry about.

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