First a little history on PMR446:
In 1997 Europe allocated a portion of the 446MHz frequency band for a new licence exempt short range radio communication system.
The UK introduced PMR446 in early 1999, so PMR446 is a mature system.
These “inexpensive” radios are often seen as a cost effective solution to all radio communications needs.
Unfortunately, they are not all they seem.
In the PMR446 market, there are “toys” and “professional” equipment.
Specifications allow for a transmit power of 500mW (1/2 Watt).
Radios can be produced very cheaply with a much lower rated transmit power (fractions of a watt), which are the “toys” which can be purchased very cheaply on the High Street.
Radphone have replaced a number of PMR446 license free two way radio systems, because of poor performance.
The advertising claims for these units can be very misleading.
“Up to 3 miles range.” Means just that… It MIGHT work 3 miles.
(We have seen claims of up to 25 miles range!)
The range of any radio system depends on a number of things, including the height of radios above the surrounding terrain.
Range can be a number of kilometres between high vantage points, but limited to only few hundred meters if a hill or large building is between users.
Range can normally be increased by fitting a higher performance antenna.
With PMR446 equipment this is prohibited… Remember this system was intended to be “short range”.
There are eight channels available, with a number of signalling options, so you don’t hear other users who share your channel.
Oddly, the extra signalling is only in use while the radio is not being used.
Your radio is just kept quiet whilst you aren’t in conversation.
The other users are still there. You just don’t hear them, and you will cause interference to each other if you transmit at the same time.
The bottom line is PMR446 can be adequate for short range, strictly non-critical applications.
The most usable areas for PMR446 tend to be outside large conurbations, where the available 8 channels can get congested.
Radphone only supply professional grade PMR446 radios.
You might want to consider other types of two way radios…