Measuring the Carrier-to-Noise Ratio
R&S FSH
1145.5973.12 4.60
E-11
Changing the span
The span set by the R&S FSH yields extremely precise measurement results. However, signals in the
environment of the measurement channel can now no longer be detected. To give you an overview of
the spectrum outside the measurement channel, the span can be changed up to a factor of ten times
the channel bandwidth during the channel power measurement.
Press the SPAN key.
The AUTO SPAN softkey is highlighted in green to
indicate that the optimum span for the channel power
measurement is set. MANUAL SPAN is activated to
allow immediate entry of another span.
Using the numeric keys, enter a new span and
terminate the entry with the appropriate unit, or
Change the span with the rotary knob or the cursor
keys and terminate the entry with the ENTER key or
the MANUAL SPAN softkey.
The largest permissible span for the channel power measurement is ten times the channel bandwidth.
With larger spans, the result of the channel power measurement would be increasingly imprecise,
because too few points of the trace occur in the channel to be measured.
Press the AUTO SPAN softkey to reset the optimum span.
To return to the menu for carrier/noise measurement, press the MEAS key.
