Sunday, 1 May 2016

What are PMR 446 Walkie-Talkies?


What's 446?



Have you come across PMR radios and wondered what they are or how they worked? ..No?
Well if next year's summer holiday involves a skiing trip or similar outdoor adventure you may find yourself purchasing a set of these radios to help keep in touch with friends and family.
They offer fantastic short range communication which can be very useful in poor mobile signal areas. They are cheap to buy, license free and universally compatible with other makes and brands making larger networks very easy.

What is PMR 446?


Personal Mobile Radio (PMR) is a European license free citizens band radio system operating on the 446Mhz UHF FM frequency using 16 channels. Most consumer walkie talkies use the first 8 channels. So generally you will just be using channels 1-8 exclusively.
PMR ChannelFrequency (MHz)
1446.00625
2446.01875
3446.03125
4446.04375
5446.05625
6446.06875
7446.08125
8446.09375
9446.10625
10446.11875
11446.13125
12446.14375
13446.15625
14446.16875
15446.18125
16446.19375
It is completely open frequency to use as you like. Walkers, bikers, small businesses or kids playing down the garden all share the basic 8 channels.
As everyone has to shares these channels they can become congested so added features like ctcss and DCS squelch coding (on certain Handsets) allow the user/group to talk with no channel chatter interference.
This system has become very popular across Europe......




1. Equipment


Although this band is license free and open to everyone, there are some rules and regulations regarding the equipment you are allowed to use. Two particular rules state that all PMR446 walkie-talkies must be limited to 0.5W of power and have a fixed antenna which means that although these radios will be quite effective to about 2 miles, any long distance capabilities of these handsets is limited.


2. Price


Although using the 446Mhz band is completely free the Handsets are not.  New Handset prices can vary from around £10 at the lower end of the market to over £200 at the very highest point.  Usually the cheaper radios are offered as a twin pack whereas the upper priced models come as a solo unit.

More for you money?

A higher priced radio doesn't necessarily mean more power or range.
All legal PMR Walkie-Talkies (exc professional PMR) are restricted to low power 0.5W and a fixed Antenna by European treaty.  Manufacturers must build to this standard. No modifications are allowed.
So basically all PMR446 Walkie-Talkies are pretty much the same. The same power, the same range (pretty much). The high end models may offer a few extra functions but everything stays the same. Perhaps one model might have a slightly longer range than others because the antenna is better. Minor things.

3. Applications


PMR446Mhz has caught on in a big way over the last decade or so. Sales have rocketted and these days it strange not seeing someone with a set whilst out on a country walk. These things are everywhere!
From shop keepers, joggers, ramblers, bikers, motorcycle  tutors and families just keeping in touch this technology offers free accessible short range communication.  Anyone can go out and buy a cheap set and get on air without a license.




Uniden/Binatone Marine 900 Waterproof PMR