Tuesday, 17 December 2013
How to choose two way radios
When choosing two way radios for personal use, you will be choosing from a few categories. If you're in Europe, there is a market of PMR446 radios to choose from. In the US, you can choose from a range of FRS radios, or GMRS if you get a license.
Now, there will be some things you need to consider. The price - how much are you willing to spend? The range - more on this later. Do you need a waterproof radio? This will increase the price.
Now, the range is a complicated topic. It's not as simple as just looking at the claim by the manufacturer. In fact, most PMR446 radio and most FRS radios will have a similar range, even though the range claims vary wildly. The best way to do it is completely ignore the manufacturers range claim. The range that they tell you is actually the line of sight - eg. between 2 mountains with nothing between the two radios. In this situation, as long as there are no obstructions, the radios could reach possibly as far as a few hundred miles.
This situation is not realistic or representative of everyday situations at all, so this is why I say to completely ignore the manufacturers range claims. I have used many radios, and even top of the range £400 Motorola digital radios will not reach 50 miles or anything near it in a city, without using additional infrastructure.
You can generally expect license free radios to reach maybe 2 or 3 blocks away in a city, or about 2 or 3 miles out in the country. This range will hardly vary at all whether you buy a "50 mile" radio or a "5 mile" radio.
The reason that range varies in different environments is because of what is around. In the city, there lots of obstacles which block the signal, reducing the range. In the country where there are not many obstructions, the radio will usually work as far as you can see, which in a flat area will be as far as the horizon.
I find that the best way to judge a radios range is by its appearance. If the antenna looks too tiny, like in a walkie talkie watch, then the range probably won't be good. If it looks reasonably sized, then it will be competitive with most of the walkie talkies you have the option of buying.
Buying the most expensive radio on the market will not guarantee the best range. Often, there are some expensive radios aimed at businesses, which are only so expensive because they are made slightly more rugged than the cheaper ones.
Feaures vs price
Now lets move on to price. You have to consider what features you want.
Radios with no CTCSS or DCS will be cheaper than radios with it. Its definitely worth getting a radio with at least CTCSS so you can filter out any other users who might be on the same channel.
You want to buy a good enough quality radio for it to last, you don't want it to break straight away, but generally you can trust all but the absolute bargain basement radios to be reliable.
You also might want to consider a waterproof radio. If you will be using it outside in the rain or near any bodies of water, then its probably worth a bit extra for a waterproof model.
Another thing to consider is the battery life. Manufacturers may make claims for battery life, and you can usually trust these more than their range claims. You should check if the radio uses replaceable batteries or a specific battery for the radio, like in phones. Some radios may have a battery pack that can be replaced with disposable (or rechargeable) batteries, which will nearly always be either AAA or AA batteries. You should compare the capacity of the batteries if rechargeable battery packs are used by the radios.
For the American market, you also have GMRS radios, for which you need a license. (Don't use these radios in Europe as its not legal here.) These radios will have a longer range than FRS when used on the high power channels, simply because of the higher power. The range will not vary much between GMRS radios, so again, completely ignore the manufacturers range claims. These radios can be expected to work slightly further than the lower power FRS radios, but not hugely further. Maybe double the range in urban areas, and probably only 1.5 times FRS range in the country, unless there are a lot of trees around. If there are many trees, then the extra power will give a lot more range than FRS because it allows the signal to push through barriers more, such as trees or buildings.
GMRS radios can also use repeaters, which will massively increase the range. A repeater works by listening for a radio signal on one channel, and then transmitting it back out at the same time on another channel, at a higher power. Repeaters are usually sited quite high up ie on the top of a hill, which allows them to receive and transmit much further because there are less obstructions
I hope this information has helped you, any comments or questions are welcome in the comments section below.
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