Instructions

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Set Ref opens a numeric keyboard from which the reference level can be set
directly as a numeric value in dBm or dBuV.
Set Step creates a pop-up menu from which the increment/decrement step size can
be set as 1dB, 2dB or 5dB.
Ref-/Ref+ increments or decrements the reference level value by the
step size set with the Set Step key.
Note that setting the Reference Level to a resolution of 1dB is a feature of 2nd generation
hardware only, indicated on the instrument’s Status screen by RF-Control firmware version
0.00-2.00 (or later). If, after downloading an update, the RF-Control firmware still indicates
version 0.00-1.xx then the Reference Level can only be set in 20dB steps as described in the
original documentation provided with the instrument at time of purchase.
4.5.3 Maximum Signal Levels
Signals that exceed the reference level may result in measurement errors even where the
excess signal is outside of the current span.
The maximum allowable input is +25dBm or +132dBuV of RF power (approximately 4 volts
RMS), or 50V DC. Applying a signal above these levels could damage the unit and such
damage would not be covered by the product warranty.
Signals that would cause the trace to rise above the reference level are indicated by a red arrow at
the top of the graticule. In addition, overload of the ADC can occur which is indicated by a warning
message below the graticule.
4.5.4 Level/Limits > Scale/Shift
Enables the scaling of the graticule to be changed from 10dB/div (the default) down
to 1dB/div. For scales of 5dB/div or less, it becomes necessary to move the
graticule window up and down to view different areas of the trace. Shift keys are
provided to do this.
Scale brings up a pop-up menu from which 10, 5, 2 or 1dB/div can be selected.
Shift Up/Down moves the graticule window up or down in one division
steps.
4.5.5 Level/Limits > Offset/Tables
Amplitude Offsets and Compensation Tables are only available when Option U02 is
installed.
Clear All turns off any offsets and any compensation tables that were set to on.
Set opens a new control menu with keys as described below.
75 Ohm adds a fixed offset to compensate for signals coming from a 75 Ohm source.
Fixed Offset enables an offset between -50.0 and +50.0dB to be added to the reference level.
Take care not to overload the input.
Comp. Table enables a file to be loaded that compensates for frequency dependent external devices
such as antennae.
On and Off turns the currently selected offset or compensation on or off.
Set Offset opens a numeric or Tab/Jog screen from which the fixed offset can be set.
Select Table opens a file recall screen for compensation tables created in PSA-Manager.
Scale/
Shift
Scale
Shift
Down
Shift
Down
Offset/
Tables
Clear
All
Set
Set
Ref
Set
Step
Ref
-
Ref
+