Hertz The dimension of the unit hertz is 1/time (1/T). Expressed in base SI units it is 1/second (1/s). In English, "hertz" is also used as the plural form. As an SI unit, Hz can be prefixed; commonly used multiples are kHz (kilohertz, 10 Hz), MHz (megahertz, 10 Hz), GHz (gigahertz, 10 Hz) and THz (terahertz, 10 Hz). One hertz simply means "one cycle per second" (typically that which is being counted is a complete cycle); 100 Hz means "one hundred cycles per second", and so on. The unit may be applied to any periodic event—for example, a clock might be
Hartley (unit) digit, a ban corresponds to a decimal digit. A deciban is one tenth of a ban; the name is formed from "ban" by the SI prefix "deci-". One hartley corresponds to log(10) bit = ln(10) nat, or approximately 3.322 Sh, or 2.303 nat. A deciban is about 0.332 Sh. Though not an SI unit, the hartley is part of the International System of Quantities, defined by International Standard IEC 80000-13 of the International Electrotechnical Commission. It is named after Ralph Hartley. The term "hartley" is named after Ralph Hartley, who suggested in 1928 to measure information using a logarithmic base