Keysight Technologies FieldFox B Series User Manual page 649

Keysight Handheld Analyzers
N99xxB User's Guide
28 Noise Figure Mode (Option 356)
Noise figure requires these options:
—
— Preamplifier (Option 235)
—
—
Not required, but recommended for improved accuracy:
—
Noise figure mode sets the sweep to
connecting a noise source, before beginning any measurements.
IMPORTANT! Noise Figure mode uses DC variable voltage source (VVS) –
(Option 309) during the measurements. The voltage might be as high as
28V during the measurement. During the noise figure measurement,
always make sure there are no voltage sensitive devices connected to the
DC SMB output port. When you exit the Noise Figure mode, the VVS
voltage is reset to 1V to avoid potentially damaging your devices. Refer to
"Variable Voltage Source (Opt. 309)" on page
When you initially change the FieldFox m ode to Noise Figure, the FieldFox
displays the following message for ten seconds:
"Ensure your Noise Source is connected to the VVS DC Output
It (VVS) will be driven up to +28V during the measurement".
Spectrum analyzer mode (Option 233—Combination Analyzers Only)
DC variable voltage source (Option 309)
Noise source (Refer to
https://www.keysight.com/us/en/assets/7018-03314/data-sheets/59
90-9783.pdf)
External preamplifier (U7227A/C/F and U7228A/C/F). Refer to
www.keysight.com/find/usb-preamp.
762.
Continuous OFF
649
to allow time for