Agilent Technologies 8564EC Service Manual page 396

All of the assemblies are extremely sensitive to electrostatic discharge
CAUTION
(ESD). For further information regarding electrostatic cautions, refer to
"Electrostatic
Chapter 1 .
Using an active probe, such as an 85024A, with a spectrum analyzer is
CAUTION
recommended for troubleshooting the RF circuitry. If an 1120A active
probe is being used with a spectrum analyzer, such as the 8566A/B, or
8569A/B having dc coupled inputs, either set the active probe for an ac
coupled output or use a dc blocking capacitor (11240B) between the
active probe and the spectrum-analyzer input. Some spectrum
analyzers can be set to ac coupled. Failure to do this can result in
damage to the analyzer or the probe.
Chapter 11
Discharge""Electrostatic Discharge Information" in
Synthesizer Section
Introduction
523