RF Counters

RF counters measure the frequency of a radio frequency signal directly, extending frequency counting well beyond the range of a general purpose universal counter.

Keysight supplies this range. Maximum input frequency is the defining specification, and above a few gigahertz a prescaler or a dedicated microwave input is required. Resolution depends on gate time and ultimately on the timebase, so an oven-controlled or externally referenced oscillator is worth specifying where absolute accuracy matters. Confirm the sensitivity at the top of the frequency range, since a counter that will not trigger on a weak signal cannot measure it however wide its stated range.