Spectrum analyzer mainframe is a wide band, very sensitive receiver. The received frequency spectrum is slowly swept through a range of pre-selected frequencies, converting the selected frequency to a measurable DC level, and displaying the same on the CRT of the Tektronix 2782. The CRT displays received signal strength against frequency. Resolution Bandwidth 3 Hz 10 MHz Resolution bandwidths from 3Hz to 10MHz in a 1, 3, 10 sequency and mixer input level decoupling from RF attenuator by up to 30 dB External waveguide support to 325GHz with frequency calibration to 1.