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equivalent Start/Stop frequencies are stored. Other parameters such as RBW are not affected
(unless set to Auto).
3. Trace States are files which contain not only the frequency span, but the RBW, the Level
setting and the graticule scale and units. Up to 999 trace files can be stored and are recalled
from the Traces/Stores control screen - see section 4.6.1.
4. The hard key marked
“Presets” brings up a menu of set-up states - see section 0. Note,
however, that these change many parameters of the instrument simultaneously.
7.2.5 Using Custom Presets (when available)
Custom Presets is only available when Option U01 is
fitted. It is accessed using the Presets hard key - see
section 0.
Pressing the Custom Presets key brings up a menu
as shown.
Custom Presets is an extended version of the User Preset from which multiple presets can be
saved or recalled by entering just a number. To save a new preset, set up the instrument as
required and press the Save Preset key followed by a number.
Each Preset is a special type of Setup file stored in the SETUPS directory with a file name of
the form $PST0001 where the $ is fixed and the next three characters (default PST) can be
changed to create multiple groups of presets. The last four characters represent the number by
which the preset is saved or recalled. Any number in the range 1 to 9999 can be used, although
the number of presets simultaneously available is set by the directory limit of 999 files.
Applications for which Custom Presets might be used include frequency selection via channel
numbers, or repetitive steps within a test environment.
7.3 Measuring Relative Amplitude
When both measurement markers are turned on, a readout is provided of the difference
between them in terms of both frequency and level.
A common requirement is to measure the signal amplitude at a specific frequency under
different conditions. The PSAxx02 provides a convenient method of doing this.
Having measured the amplitude in the initial condition using marker M1, the value can be fixed
from the Marker Setup sub-group menu (Traces/Markers > Marker Setup > Fix/Unfix M1). The
M1 readout shows Fx at the left hand side. With the new condition applied, the measurement
can be made again by moving M2 to the same frequency using the key Move M2 to M1. The
difference in amplitude level can then be read directly.
To return M1 to normal operation, press Fix/Unfix M1 again. See section 4.7.1.
7.4 Triggered Operation
Triggered operation is only available when the upgrade option U01 is fitted (see section 6).
Triggering is used either to start or stop the sweep, or to initiate logging of sweeps or screen
images. The trigger can be generated manually (by a key press), externally (from the trigger
input) or internally from the sweep in combination with a limit line or limit pattern.
For a description of Triggered Sweep see section 4.4.3.3. For a description of Triggered
Logging see section 7.7.
7.4.1 External Trigger Input
The external trigger input is provided via the 3.5mm jack socket at the top of the
instrument. This can be converted to a standard BNC socket using the adaptor
provided. The selection between positive or negative transition triggering is made from
the Sweep Trigger or Logging Trigger functions. It has a TTL threshold and a high input