The Keysight / Agilent / HP 8559A is a 0.01 to 21 GHz spectrum analyzer plug-in for use with both the 853A and 180-series display. The high performance and convenient operation of this economical unit is ideally suited for a variety of applications in production, R&D or field service environments.

Preset the 8559A to the color coded, "basic-operation" settings, and use the coupled controls to make most measurements in three easy steps. Tune to the signal; the LED readout displays its frequency. Zoom-in on the signal by reducing the span width; the resolution bandwidth, video filter, and sweep time automatically change to an optimum value for a calibrated display. Then, change the reference level to bring the peak of the signal to the top of the screen for the most accurate amplitude measurement. A signal identifier is available in all bands to provide assurance of correct measurements.

Signal levels can be read directly in dBm from CRT without the use of external standards or calculations. The signal level represented by the top CRT graticule line is always indicated by the reference level control, and vertical scale factors of 10 dB/div, 1 dB/div, or linear can be selected.