When looking to buy a 2-way radio, one of the first questions we ask about is what range or distance that two way radio is able to communicate reliably with another person.

Well, 2 way radio range depends on several things. These include:

• What band or frequency is the radio operating on
• What is the power (in Watts) of the transmitter
• What antenna is being used
• What type of signal is being communicated? (e.g. voice AM/FM/SSB, digital, morse code)
• Is there any interference (hash noise or other stations)
• What is the path between the sender and receiver?
• Are there trees, hills or buildings blocking the path of your radio signal?
  

The frequency of the signal makes a difference because some signals, such as VHF and UHF bands, work pretty much line-of-sight. The sets send and receive on the same frequency or channel. This is called working simplex.

However many public service networks (e.g. police, fire and ambulance), big commercial or government organizations will route their vhf or uhf traffic through radio repeaters, on radio towers or on top of tall buildings, and these can extend the radio signals right around your town or city. This is known as working duplex, and not all two way radios can do this.

Radios that can do duplex communications will transmit on one frequency and receive on another. What you send out gets picked up by the repeater (if you are in range) and re-transmitted immediately on a different frequency. But everone using that repeater will be set up to do the same, so you can talk to each other without confusion.

Cheap two way radios, such as those designed for CB, FRS and GPRS frequencies are made as simplex radios. The same applies to most MURS and Business Band radios, unless your company or organization owns its own repeater station - and all the radios are licensed and set up for the appropriate radio channels.

So what I am saying here is that these cheap radios will not give you much range at all.So treat the manufacturer's claims about 2-mile radios or 10-mile radios with a great deal of suspicion. They are sure to be overly-optimistic!

In cases where you need to talk hundreds of miles or more, over areas where repeater stations won't do the job and satcom Satellite Communications is not an option, there is the time-tested method of HF shortwave two way radio communications.

When propagation conditions are favorable, HF radio signals can bounce off the atmosphere and come down to earth again many miles from where your HF radio station is located. It calls for larger antennas than other radios, and you need to use different radio frequencies for daytime and night time use.

Ships at sea use HF radio to talk around the world, and so do licensed Ham Radio operators, government departments and the military. They also have communications satellites... but they are a little bit above our budget, I'd say.

It takes some skill to set up and adjust these shortwave antenna systems and to know which frequencies or channels in the HF bands will get through to the people you are trying to reach. So HF radio operators and their equipment need to be licensed, and can only operate on the frequencies set out in the terms of your license to operate. In the USA, this piece of paper comes from the FCC.

HF radio is serious radio communications, and should not be confused with CB radio - which needs little skill and no license to operate. It is true that the old CB radio service is set up on part of 27 MHz, which is a very small part of the HF bands. But comparing the two radio services is like comparing a kids pedal car to a Formula One racer.