R&S FSW-K7, Руководство пользователя

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Measurement Basics
R&S
®
FSW-K7
44 User Manual 1173.9240.02 ─ 23
Message Description
"Ext. Generator Command Error!" Missing or wrong command in the generator setup file
(see
Chapter 4.7.4.3, "Generator Setup Files" ,
on page 37
"Ext. Generator Visa Error!" Error with Visa driver provided with installation (very
unlikely)
Overloading
At a reference level of -10 dBm and at an external generator output level of the same
value, the R&S
FSW operates without overrange reserve. That means the R&S FSW is
in danger of being overloaded if a signal is applied whose amplitude is higher than the
reference line. In this case, either the message "RF OVLD" for overload or "IF OVLD"
for exceeded display range (clipping of the trace at the upper diagram border = over-
range) is displayed in the status line.
Overloading can be avoided as follows:
●
Reducing the output level of the external generator ( "Source Power" on page 74
in "External Generator > Measurement Configuration")
●
Increasing the reference level ( Reference Level in the "Amplitude" menu)
4.7.5 Output for Noise Sources
The R&S FSW provides a connector (NOISE SOURCE CONTROL) with a voltage sup-
ply for an external noise source. By switching the supply voltage for an external noise
source on or off in the firmware, you can activate or deactive the device as required.
External noise sources are useful when you are measuring power levels that fall below
the noise floor of the R&S
FSW itself, for example when measuring the noise level of
an amplifier.
In this case, you can first connect an external noise source (whose noise power level is
known in advance) to the R&S
FSW and measure the total noise power. From this
value you can determine the noise power of the R&S FSW. Then when you measure
the power level of the actual DUT, you can deduct the known noise level from the total
power to obtain the power level of the DUT.
The noise source is controlled in the "Output" settings, see "Noise Source Control"
on page 127
4.7.6 Receiving and Providing Trigger Signals
Using one of the TRIGGER INPUT / OUTPUT connectors of the R&S FSW, the
R&S FSW can use a signal from an external device as a trigger to capture data. Alter-
natively, the internal trigger signal used by the R&S FSW can be output for use by
Receiving Data Input and Providing Data Output