Keysight FieldFox B Series User Manual page 663

Keysight Handheld Analyzers
N99xxB User's Guide
29 Noise Figure Mode (Option 356)
Noise figure requires these options:
– Spectrum analyzer mode (Option 233—Combination Analyzers Only)
– Preamplifier (Option 235)
– DC variable voltage source (Option 309)
– Noise source refer to
https://www.keysight.com/us/en/assets/7018-06515/configuration-guid
es/5992-3701.pdf
Not required, but recommended for improved accuracy:
External preamplifier (U7227A/C/F and U7228A/C/F). Refer to
www.keysight.com/find/usb-preamp.
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".
When connecting a Smart Source similar to a U1832/U1833A/B/C/D,
please wait 10 to 20 seconds, for the FieldFox analyzer to recognize your
device.
790.
Continuous OFF
663
to allow time for