D-Scan Cycle; Spectrum Display Norm (Normal) - R&S EB200 Manual

EB200 Manual
CYCLES
REF LEVEL
DISPLAY LIMITS
Initially the upper value of the DISPLAY limits is firmly linked to the reference level.
If, however, the SW option EB200FS (Field Strength Measurement) is fitted, the upper value of the
DISPLAY LIMITS can be configured independent of the reference level. In this case it can be varied in
the range from 0 to 250 dB in 10-dB increments. Shifting the display range to values near 250 dB is
only necessary if very high antenna k-factors are to be taken into account.
The lower value is calculated from the upper value of the DISPLAY limits minus the current RNG.
Note:
In D-SCAN the measuring time is only important when it comes to setting the D-SCAN SPEED to
MTIME PER CHANNEL. In this case frequency scanning will in fact be performed, the results being
shown in a spectrum. A measuring time other than the DEFAULT can only be adjusted with IF sections
that are fitted with the DDC2 (see also "SYSTEM menu" on page 40).

3.18.3.2 D-SCAN cycle

When D-SCAN (digital scanning) is running (RUN is shown in inverse video), the synthesizer is being
tuned to the exact frequency of the channels. Channel spacing always equals half the IF bandwidth.
The level of each channel is being measured. The displayed spectrum is derived from the sum of the
measured levels
The number of channels is derived from the span frequency divided by half the IF bandwidth. The
higher the number of channels is, the longer takes the D-SCAN cycle.

3.18.3.3 Spectrum display NORM (normal)

The display always shows a spectrum of 190 level lines according to its pixel resolution and it does not
depend on the number of channels. If the number of channel exceeds 190, the measured values of
several channels will be combined in a way that the respective highest level will be displayed. The
frequency of the channel with the highest level will be stored in the background so that the correct
frequency can be set for the marker-to-peak process.
However, through the remote control interface, all measured channels are always output. In this case
the representation reduced to 190 lines is not available.
If the number of channels is smaller than 190, several level lines will get the same length from which a
spectrum of rough steps is derived.
The level is indicated by 35 pixels in the y-axis. The resolution can be set in four steps by the RNG
softkey. In order to avoid overdriving of the receiver, the reference level is set to the highest expected
positive signal level. Every desired reference level can be set via remote control by command
VOLTage:AC:RANGe in the range of 0 to 110 dBµV.
4052.2000.02
Number of sweeps
The reference level determines the largest level value to be represented. It can
be set in the range of 0 to 110 dBµV in steps of 10 dB. Also intermediate values
can be set via remote control or by means of direct number input.
Display range of the spectrum:
1 to 1000 / infinite
eg –20 dBµV to 60 dBµV
3.34
Operation
E-7