Rf Cnt Gate; Sensitivity; Squelch - HP 8921A User Manual

RF Cnt Gate

Sensitivity

Squelch

RF counter gate specifies how long the RF counter samples the signal before
displaying the frequency. Specifying a shorter gate time may enable you to see
frequency fluctuations that might not be seen using a longer gate time.
RF Analyzer sensitivity adds about 6 dB of sensitivity for the ANT IN port when
is selected.
High
Operating Considerations
Selecting sensitivity may cause Spectrum Analyzer
High
uncalibrated when the ANT IN port is used (a message appears when this occurs).
High-level AM measurements may be distorted when high sensitivity is used with
the ANT IN port.
This setting determines the squelch operation when demodulating FM, AM or
SSB signals. Three settings are available:
• Pot uses the front-panel SQUELCH knob for squelch level adjustment.
• Open disables squelch operation.
• Fixed sets the squelch to a fixed level, disabling the front-panel SQUELCH knob
control.
Operating Considerations
Most measurement processes on this screen are not displayed if the incoming
signal falls below the squelch level (with the exception of
measurements are replaced by four dashes (- - - -) to indicate they have been
'squelched'.
The decoder and Oscilloscope measurements are also disabled when the signal
has been squelched.
Spectrum Analyzer measurements are not affected by the squelch setting
(although squelch still affects whether the demodulated signal can be heard while
viewing the RF signal).
1. Optional on Test Sets
Chapter 17, RF Analyzer Screen
Field Descriptions
1
measurements to be
). The
TX Power
423