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Can I make some attenna to connect to a murs or FRS radio from the station at the bottom of the hill(because it will be staionary). So if the radio w/o the super attenna only has a short range but the stationary radio will send and receive all the signals from the normal one correct? If theirs a normal radio at one end then another somewhere else could the super attenna from the stationary extend their range?
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Antennas come in 2 basic varieties, OMNI and DIRECTIONAL. An OMNI antenna is one that works in all directions. A whip antenna is a good example of an OMNI antenna. Directional antennas are antennas that pickup or transmit in one direction better than others. The old TV antennas on many roofs are good examples of DIRECTIONAL antennas. The other things important about antennas are the WAVELENGTH of the radiator, and the GAIN in any direction.
The WAVELENGTH refers to the length of the radiator . Since this is an audio site, I'll use an sound example, and talk about a wireless mic receiver antenna. Most of us have seen a Shure L4 or LX wireless system. These come with 1/4 wave antennas. That means that the antenna is 1/4 as long as the wavelength it operates on. These Shure systems operate in the VHF range of 169 - 209 MHz and their 1/4 wave antennas are about 18" long. A 1/2 wave antenna for the same system would be about 36" long, and a full wave antenna would be about 72" long. 1/4 wave antenna work OK (as long as they are 1/4 of the actual band wave) but only really pick up about 1/4th of the signal. A full wave antenna picks up the entire signal, and therefor suffer from less dropouts, and has a hotter signal to send to the receiver.
Transmission works the same way. You can transmit over a shorter wavelength antenna, but you will send out more signal over a longer wavelength antenna.
GAIN refers to the signal strength of the antenna, as well as signal strength in any direction. A 1/2 wavelength antenna will have more GAIN than a 1/4 wavelength antenna (in all directions). For a directional antenna, the antenna may have 10 or 20 dB more GAIN in one direction than all others. Directional antennas work better because of two things. One, they keep out stray signals (to a degree) from entering the receiver. Two, they increase the gain of the signal in one (or more) directions, so you can "aim" the antenna. There are different types of directional antennas. The common TV antenna is called a Log-Periodic Dipole Array or LPDA, the common satellite dish is called a Paraboloid Reflector. Other common types are Yagi, Screen and Corner reflectors, and Dipoles.
For your short (1 mile) needs, simply using longer whip antennas, or using a set of basic directional antennas would be a good idea.
MURS radios are set up to take remote antennas. Like a CB or HAM Radio, MURS radios have an antenna connector that allows you to use different ant types depending on your needs. Unfortunately, FRS/GMRS radios (at least all the handheld ones that I have seen) all seem to use built in antennas with no provision for using an external one. There may be GRMS radios out there that have external antenna capabilities, I just have not seen them.
Actually, after thinking about what you want to do, I was also thinking a CB Radio system (26.965-27.405 MHz) would do the job for you as well. You could get 2 inexpensive mobile CB radios, a pair of 120 to 12 volt adapters and some good whip or directional antennas all from a place like Radio Shack for way under $200 bucks and just pick a CB channel (other than channel 9 which is used only for emergencies) that is clear and use them. No license required, and they will surely transmit more than a mile! If you go the CB route, make sure you use mobile CBs (like for use in a car, or base station CBs and not the Walki Talkie styles, as the handheld Walki Talkies won't have the available power as the mobile or base station units. Other than truckers, and the odd amatuer radio buff trying to skip CB signal around the globe, you should find the CB Band pretty clear these days! Also, there are many companies who sell CB radio amplifiers (AKA Linears) that will increase the transmit power of the units. These devises will be illegal if they boost the transmit power over of what is allowed by the FCC (5 watts) but they are out there, and available if people want to use them.
In fact, the more I think about this, CB is probably the way to go for this! That way you would be able to use large whips or directional antennas, and also use any other hand held or mobile CB to also communicate to your system.
Craig