The Agilent/HP 8563E is a spectrum analyzer which has a standard frequency range of 9 kHz to 26.5 GHz, with optional low-end frequency coverage to 30 Hz. 
The 8563E offers the measurement capabilities and performance traditionally found only in larger, more expensive benchtop analyzers. 
The 8563E combines outstanding phase noise, sensitivity, 1 Hz resolution bandwidths, synthesized tuning and wide dynamic range in a MIL-rugged package built to withstand harsh environmental conditions. 
The 8563E offers a complete solution for adjacent-channel power (ACP) testing of burst carrier signals using digital modulation, and the ability to measure occupied bandwidth percentage. 
The 8563E provides a low cost solution when used with Agilent 11970 series harmonic mixers or Agilent 11974 series pre-selected mixers for millimeter applications that don’t require full microwave coverage.