Which of the following is not a characteristic of UHF communications?

UHF (Ultra High Frequency) communications are known for several distinct characteristics that enable their functionality across various platforms. Line of sight capability is a fundamental trait of UHF systems, meaning that effective communication occurs when the transmitting and receiving antennas are within sight of each other. This characteristic is crucial for many military and aviation applications where UHF is widely employed.

UHF is also commonly utilized for secure voice communication, making it suitable for military operations that require confidentiality in exchanges and discussions. It facilitates robust and encrypted communications vital for mission success.

In the context of air-to-air communications, UHF is utilized extensively among aircraft, allowing them to coordinate and communicate directly during operations. The bandwidth used in UHF enables multiple channels, supporting a range of communication needs in both tactical and operational scenarios.

Although UHF systems are commonly used from bases and vehicles, they are not limited to ground-based operations alone, which is why the choice indicating that they are primarily for ground-based operation is not accurate. UHF can be employed from airborne platforms as well as ground installations, further demonstrating its versatility in a variety of communication contexts.