R&S 1129.7246.03, Operating Manual

Page: 191 / 855

R&S ESU Instrument Functions
Analyzer Mode
4.160 Operating Manual 1302.6163.12 - 03
With the selection of the decimal separator different language versions of evaluation
programs (e.g. Microsoft Excel) can be supported.
Remote command:
FORM:DEXP:DSEP POIN
4.8.11.6 AF Demodulation
The R&S ESU provides demodulators for AM and FM signals. With these demodu-
lators, a displayed signal can be identified acoustically through the use of the inter-
nal loudspeaker or with headphones. The frequency at which the demodulation is
enabled is coupled to the markers. The sweep stops at the frequency determined by
the active marker for the selected time and the RF signal is demodulated. During a
measurement in the time domain (span = 0 Hz) the demodulation is continuously on.
The threshold line ( MKR->:SEARCH LIMITS:THRESHOLD ) performs a squelch
function in the demodulator. If the threshold is set, the R&S ESU LF demodulation is
switched on only when the signal to be demodulated exceeds the set threshold.
MARKER
DEMOD
The MARKER DEMOD softkey switches on the audio demodulator and calls a sub-
menu in which the demodulation mode and the duration of the demodulation can be
selected.
Remote command:
CALC:MARK1:FUNC:DEM ON
MKR DEMOD
ON | OFF
The MKR DEMOD ON/OFF softkey switches the demodulation on/off.
In the frequency range (span >0), the frequency scan is stopped at the frequency of
the active marker with demodulation switched on – provided that the level is above
the threshold line - and the signal is demodulated during the given stop time.
In the time domain (span = 0) demodulation is continuous, i.e. not only active at the
marker position.
Remote command:
CALC:MARK1:FUNC:DEM ON
AM | FM The softkeys AM and FM are selector switches one of which only may be active at a
time. They set the desired demodulation mode FM or AM. Default setting is AM.
Remote command:
CALC:MARK1:FUNC:DEM:SEL AM
CALC:MARK1:FUNC:DEM:SEL FM
SQUELCH The SQUELCH softkey enables the input of a level threshold below which the audi-
ble AF is cut off. The squelch function is associated with the internal trigger function
(
TRIGGER menu), which will be switched on automatically with the squelch.
Squelch level and trigger level do have the same value.
The default setting for the squelch is off.
Remote command:
CALC:MARK1:FUNC:DEM:SQU ON | OFF
CALC:MARK1:FUNC:DEM:SQU:LEV 80 PCT
MKR DEMOD ON | OFF
AM | FM
SQUELCH
MKR STOP TIME
CONT DEMOD