We have received many customers’ letters about how to extend the radio communication range . That maybe one of the most common issues that two-way radio users encounter is traveling out of range and losing communication with others. Those operating a fleet of radios know how frustrating this can be. The distance that a two-way radio signal can travel varies from 2 miles all the way to 30 or 40 miles. But why does the potential distance of these signals vary so much?
The effective range of a two-way radio is dependent on several variables, such as the size of the radio’s antenna, the frequency band the radio is using, the surrounding terrain, and whether the user is indoors or outdoors. It’s important to take note of all these details when troubleshooting a signal loss issue within your radio fleet.
Check the Antenna and Your Location to extend communication range
Two-way radio signals travel in straight lines and can be obstructed by buildings, hills, trees, and even your own body. It’s important that the antenna be as high up as possible, so as to increase its line of sight with other radios and maintain a better signal. Sometimes moving to a higher elevation is all that’s needed to restore communication.
Two-way radios mounted inside a vehicle suffer from interference from being encased within the vehicle. An external antenna, ideally mounted on the roof of the vehicle, will greatly reduce interference and extend the signal range.
Use a Repeater to extend communication range
A two-way radio can only transmit a limited distance on its own. That’s where repeaters come in.
A repeater system is a device that receives and re-transmits a signal with increased power from a higher elevation, usually from a tall tower or building. Repeaters can be used by police departments, ambulance services, emergency personnel and commercial businesses in order to communicate over a very large area, such as a city, or a highly obstructed area with hills, mountains, or tall buildings.
Repeaters operate on two separate but nearly identical frequencies: one that receives a signal and the other that outputs a signal. This is referred to as duplexing. To use a repeater system, you must set your radio to transmit on the repeater’s output frequency, and enable the radio’s offset mode. The radio will now transmit on the repeater’s input frequency and revert to the repeater’s output frequency when not transmitting.
Which Is Better, VHF or UHF?
Two-way radios operate within VHF and UHF wavebands.
VHF wavelengths are longer, allowing signals to travel greater distances, but making them less suitable for highly obstructed areas. UHF wavelengths are shorter, allowing them to penetrate concrete, metal, and wood much more effectively than VHF. Generally, UHF is the more popular band to use because it is a better all around signal, unless you need to transmit outdoors across great distances. Most commercial radios are capable of operating on both VHF and UHF wavebands, so it is a good idea to test both to see which one is better suited for you.