This highly versatile Tektronix 494P covers the frequency range of 10 kHz to 21 GHz in coax, and up to 325 GHz with set of waveguide mixers (sold separately). Not only is this Tektronix 494P Spectrum Analyzer programmable, but it is compact, rugged, and portable as well and in addition has built-in frequency counter which works to 325 GHz. Features Full programmability with GPIB Direct plot capability Keypad data entry Nonvolatile memory storage HELP manual built-in in ROM -117 to +40 dBm amplitude ranges 30 Hz resolution up to 60 GHz Input impedance is 50 Ohm (N connector)