GME UHF Radio Antennas
Every kind of radio requires an antenna to function, it may be internal or external but one is always there. Your mobile has a small one hidden in its body, but your CB radio can benefit significantly from a UHF antenna mounted on your roof. GME has been making telecommunications equipment in Australia for Australians since the 1950's, and their commitment to radio communications is as obvious as the antenna on a UHF handheld radio.
How Antennas Work
The key to understanding antennas is to understand the relationship between frequency and wavelength. Because light, and therefore radio, travels at a constant speed there is an inverse relationship between radio frequency and wavelength so higher frequencies have shorter wavelengths. Antennas work by resonating with the incoming radio waves, which for UHF CB have a wavelength of approximately 62.85 centimetres. The closer the antenna is to a multiple of that length the more sensitive it is to UHF CB frequencies.
What Should You Look for in a GME UHF Antenna?
When you're looking for a GME UHF antenna, there are several factors to attend to both on the antenna and how you want to mount it. The most common use is for UHF CB radios:
- Height: UHF is line of sight, so the higher your antenna is from the ground the longer range you have. There are obvious height limits when it comes to vehicles, but for home units you want to go as high as possible.
- Gain: Antenna gain is all about directionality, a higher gain antenna can pick up signals more easily in on direction than others. This is useful for vehicles as you can use the gain to shape the signal along the roadway.
- Mount: The easiest vehicle mount is a magnetic one due to its flexibility. Permanent mounts can go on the roof or bumper, and in some cases you may want to bolt the antenna into place.
UHF CB in Australia
While Citizen Band radio in most countries relies on the 27 MHz AM band, Australia uses an 80 channel UHF CB standard based on the 477 MHz FM band. The biggest advantage of UHF radio is its clarity. Where AM is subject to a wide range of interference, FM radio is not. This means that anyone in range and on the same channel can hear you clearly, which is a huge advantage for communication. That same frequency does limit UHF to line of sight communications, but that can also be an advantage as it limits the number of people on the same channel. This is particularly important, as not all the 80 channels are available to all users. Channels 5 and 35 are for emergency use only, while 22 and 23 are for data.