What is PMR 446? (A very short FAQ)
Personal Mobile Radio is the European equivalent of the Family Radio Service (FRS) in the U.S. and Canada.
Basically, is a frequency (446MHz) than can be used through out Europe (well, most of it anyway) by anyone that owns a PMR two-way radio (a development of the Walkie-Talkie, if you wish), without the need for license or any other kind of authorization. From the moment you buy yourself a PMR radio you can start using it.
The idea behind PMR (and FRS) is for it to be used for personal communications only. So, it shouldn't be used for either professional or commercial use. Typical uses for PMR are Camping/Skiing groups, Car-to-Car communications while on a long trip, Families on vacations, Families on a Shopping Centre, Planning a trip to the nearest pub with your neighbour from across the street, etc. Basically, an excelent way of saving on mobile phone calls when you're near the party you want to speak to.
FRS/PMR? Why 2 standards?
FRS and PMR are not exactly alike.
What are the differences then? FRS appeared first, and started gaining popularity in the Unites States, wich caused radio enthusiasts in Europe to start claiming the same, an unlincensed frequency for private use.
Trouble was, that the frequencies used by FRS were already in use in several European countries, wich posed an impossibility on just adopting FRS, the ERO (European Radio Office) had to chose a different (unoccupied) frequency. And the choice went upon 446MHz. But the radios are the same, they just work in different frquencies, if a different name was not used people would buy FRS radios and think they were buying 446MHz radios. Hence, a different name had to be created so that the radios could clearly state wich standard they operated in. And so, PMR was born.
FRS has 2 operating frequencies giving it 14 main channels, PMR has only 1 frequency (446) giving it 8 main channels. A Cobra MT305 FRS radio will look just alike a Cobra MT305 PMR radio, they just operate in different frequencies.
What PMR radios exist? And how much do they cost?
There is a truckload of brands and models, from well known ones, to smaller, virtually unknown brands. For more information on what brands currently manufacture PMR 446 radios I advise you to check up my Info links page (as well as for information on a lot of other stuff, like wich countries adopted PMR, reviews, etc. etc.).
You can get PMR radios from about 20 Euros up until 2500 Euros, depending on the features it comes with. But, the big advantage is that the 20Eur. radio will be able to communicate with the 2500Eur. one and vice versa (just like a cheap mobile phone can place a call to an expensive one).
More feature packed PMR radios come with CTCSS (aka. sub-channels, and most of PMR radios have this one, except the cheapest. - It's a mandatory feature in Ireland - ), digital compass, GPS, Vibration call, Voice scrambling, voice filters for crispier reception, and a lot more.
For about 50Eur. you can get quality radios, for about 70Eur. you should be able to buy a PMR with a nice amount of good features, and, over 100/120Eur. you should be able to buy a professional quality one. Some brands sell PMR radios in 2-Packs, and that usually becomes cheaper.
I'm not a child anymore, why should I use a walkie-talkie?
Well, these "walkie-talkies" are quite more developed than the ones you probably had as a child, and with a lot of different uses. Starting for the fact thet they have 500mW transmission power that gives them, with a line of sight, something like up to 3Km range (50 and even 100Km transmissions have been acomplished, but under very particular circumstances).
It's easy to use, you won't have trouble on having somehing on your children's hands that they won't know how to use if they get lost from you (heck, they can even use a mobile phone better than me, sometimes...).
It's free! You can make as many "calls" as you want knowing you'll never pay for them.
Any model with CTCSS (sub-channels), gives you 304 communication channels (8 main channels with 38 sub-channels each), so, you can be practically sure, you'll always have a free channel for you and your group.
Besides being useful, it's funny (The child in you will keep telling you that).
CTCSS, what is that? Does it matter?
If you're in Ireland, you can only use CTCSS enabled PMR Radios, so, you don't stand a chance of using non-CTCSS radios.
If you're in another European country, you can make your own decision on that. For me, it's an absolutelly indispensable feature, and here's why:
CTCSS -Coded Tone Control Squelch System, each Main Channel from PMR is divided into 38 CTCSS tones/subchannels. And the better way to explain to you how this works is by giving you an example.
Let's say you and your group are on a very crowded beach with lots of PMR users (never did find such a place, but, this is hypothetical, anyway), if there were 8 groups using PMR there already, you (the 9th users), would be in a very nasty situation, because you'd have no free channel. What CTCSS does, is to put a specific tone mixed with your communication, each tone corresponds to a subchannel, so let's say, you'd be communicating on Main Channel 5, subchannel 23. Your PMR radio would filter off all comunications on Main Channel 5 that didn't had that tone (23) mixed in the comunication, so, you'd be "sharing" Channel 5 with more people, but only hearing yourselves. This ends up on giving 304 "virtual" channels (8 x 38).
Non-CTCSS radios always operate on subchannel 0, aka. all filters off, and thus hearing all comunication on the main channel, regardless of the subchannel. Always remember , talking in a subchannel different than 0 is aimed to prevent you from hearing other people, and not to prevent the other groups from hearing you. So, don't think you have a totally private communication, anyone with a cheap PMR (too cheap to have CTCSS) will be hearing you, because they have no way to filter you off.
Usually people just want to filter everybody else off. But, if you are concerned with the privacy of your communications, you'll have to buy a model that features voice scrambling, but that's usually a kind of expensive feature.
If you have a CTCSS enabled radio, you'll have to disable it (change into subchannel 0) in order to be able to communicate with non-CTCSS radios. Otherwise, you just wouldn't hear whatever they'd say to you.
DCS - DCS is the digital counterpart to CTCSS. It has 83 subchannels that provide 664 (8x83) “virtual channels. DCS is starting to appear in newer, and usually top catalog models. The purpose is precisely the same as the CTCSS one. All radios with DCS also have “standard” CTCSS.