The UHF connector is a dated name for a threaded RF connector. The connector design was invented in the 1930s for use in the radio industry, and is a shielded form of the "banana plug". It is a widely-used standard connector for HF transmission lines on full-sized radio equipment, with BNC connectors predominating for smaller, hand-held equipment.
The name "UHF" is a source of legitimate confusion, since the name of the connectors did not change when the frequency ranges were renamed. The design was named during an era when "UHF" meant frequencies over 30 MHz. Today Ultra high frequency (UHF) instead refers to frequencies between 300 MHz and 3 GHzand the range of frequencies formerly known as UHF is now called "VHF". Further adding to the confusion, the so-called "UHF" connectors are only well suited for the lower-VHF range and lower; they perform poorly for the higher modern UHF region. A more appropriate name would be "HF" connectors.
There is no active specification or standard governing the mechanical and electrical characteristics of the so-called "UHF" connector system making it effectively a deprecated design.