R&S 1129.7246.03, Operating Manual

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Operating Manual 1302.6163.12 - 03 4.109
R&S ESU Instrument Functions
Analyzer Mode
The UNIT softkey opens a submenu to select the unit for the level axis.
The default setting is dBm.
In general, the R&S ESU measures the signal voltage at the RF input. The level dis-
play is calibrated in rms values of an unmodulated sinewave signal. In the default
state, the level is displayed at a power of 1 mW (= dBm). Via the known input resis-
tance of 50
Ω
or 75W, conversion to other units is possible. The units dBm, dBmV,
dBµV, dBµA, dBpW, V, A and W are directly convertible.
Remote command:
CALC:UNIT:POW DBM
RF INPUT
AC | DC The RF INPUT AC/DC softkey toggles the RF input of the R&S ESU between AC
and DC coupling.
Remote command:
INP:COUP AC
RF ATTEN
MANUAL The RF ATTEN MANUAL softkey allows the attenuation to be entered irrespective of
the reference level.
The attenuation can be set in 5 dB steps between 0 and 75 dB.
Other entries will be rounded to the next higher integer value.
If the defined reference level cannot be set for the given RF attenuation, the refer-
ence level will be adjusted accordingly and the warning "Limit reached" will be out-
put.
RF ATTEN MANUAL is the default setting.
Remote command:
INP:ATT 40 DB
RF ATTEN
AUTO The RF ATTEN AUTO softkey sets the RF attenuation automatically as a function of
the selected reference level.
This ensures that the optimum RF attenuation desired by the user is always used.
Remote command:
INP:ATT:AUTO ON
10 dB MIN
ON | OFF The 10 dB MIN ON/OFF softkey determines whether or not the 0 dB position of the
attenuator is used when the attenuation is set manually or automatically.
The default setting is ON . This means the R&S ESU always leaves at least 10 dB
RF attenuation on in order to protect the input mixer.
The 0 dB position cannot be switched on manually. This prevents that 0 dB are set
by mistake especially for measurements on objects with high signal voltage.
Remote command:
INP:ATT:PROT ON
Side menu
dBpT
The value 0 dB cannot be switched on unless the 10 dB MIN ON | OFF softkey is
set to OFF in order to protect the input mixer against accidental overload.