General Dynamics R2600 Series, Руководство оператора

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Specific controls which further configure the
MONITOR mode are located within the RF zone
when MONITOR is first selected. The specific
entry fields are as follows.
Preset
The preset entry field provides a convenient way
to enter a bandwidth, frequency, modulation
type, and code synthesizer format for the unit by
recalling preset data from non-volatile memory.
If a preset is not to be used, enter the desired
information at each of the fields.
NOTE
If a preset had been selected and changes are
made to any of the preset values, the "Preset:"
field will have dashes through it, indicating
the preset is no longer selected.
B/W
Selects either wide or narrow IF bandwidth of the
unit via softkey selection.
Freq
Enter the desired monitor frequency using
keypad or tuning knob.
Attenuation
Selects the amount of attenuation at the RF input
to the monitor receiver using softkeys. Select-
able input attenuation is useful in adjusting
displays for a wide range of input levels, as well
as for use in high RF field environments where
intermodulation may cause desensitization of the
receiver.
Mon RF In
Selects the RF input port via softkeys. The RF
I/O port contains an RF load and should be used
for direct connection to the radio under test. The
ANT port accesses the unit's sensitive receiver
and should be used with an antenna for
"off-the-air" reception. Selection of the ANT
port is indicated by a red LED adjacent to the
ANT connector.
CAUTION
Do not apply input power to the ANT input
port. In the event RF power is inadvertently
applied, the port is protected by an in-line RF
fuse. This fuse may be accessed by un-
screwing the front of the BNC connector out
of the front panel. Refer to paragraph 2-2.4.1
for additional detail.
Modulation Type
Selects the type of modulation via softkeys. AM
and FM are standard selections. Phase
modulation (option) is selected by pressing the
sofkey labeled PM, and provides the cpability to
generate and monitor PM signals.
3-5.1.1 Phase Modulation
Phase Modulation provides the capability to
generate and monitor PM signals. This is an
additional softkey selection in the RF Control
zone for the modulation type (figure 3-5).
In Generate mode, narrow-band operation
provides user control of the audio signal
deviation from 0.50 to 2.00 radians in 0.01 radian
steps. In wideband operation, the audio signal
deviation ranges from 2.0 to 10.0 radians in 0.a
radian steps. Tones generated from the Audio
zone are limited in frequency from 300 Hz to
3000 Hz for phase modulation
NOTE
Phase Modulation is a hardware option that
is installed at the factory. To determine if
Phase Modulation is available in the
Analyzer, examine the Standard Options
display screen (accessed via SPF/Version
25