Radio frequency radiation is usually measured in kilohertz (kHz), megahertz (MHz), or gigahertz (GHz). JTRS was originally planned to use frequencies from 2 megahertz to 2 gigahertz. Frequencies of the order of megahertz (MHz) are above the usual range for mechanical filters. All times are Coordinated Universal Time (UTC), and all radio frequencies in megahertz (MHz). The frequencies of sonars range from infrasonic to above a megahertz. Baseband video uses frequencies up to several megahertz. Short wave diathermy operations use the ISM band frequencies of 13.56, 27.12, and 40.68 megahertz. The channel itself occupies several megahertz of bandwidth. There are some websites which advertise "battery desulfators" running at megahertz frequencies. These systems were based on high frequency (HF) at 13.56 megahertz. For example, a one-microsecond pulse has a Rayleigh bandwidth of one megahertz. A 1 megahertz radio signal has a wavelength of . The fastest possible interrupt frequency is a little over a half of a megahertz. One of the most important factors in analog television is signal bandwidth, measured in megahertz. Column 1 is the test frequency in megahertz in this case.