very high frequency (secure)
Definition/Scope: Very High Frequency (VHF) frequencies fall directly beneath the Ultra high frequency, UHF making it the fifth highest. It is generally used by FM radio, television, land based stations and air traffic control stations to name a few. VHF is usually restricted to local areas due to environmental conditions such as land features it is less affected by buildings. One of the primary differences between normal VHF and VHF (secure) is that there is a cryptographic capability in the secure mode. One of the capabilities would include channel hopping which is jam resistant.
Broader Terms:E-2 Hawkeye
Narrower Terms:AN/ARC-201 SINCGARS