R&S FSH Measurements using the power sensor
1309.6275.12 4.75 E-2
Selecting the unit for the power readout
T
he R&S FSH can display measured power in relative units (dBm) or in absolute units in Watts (W,
mW, KW, nW and pW). A reference level in dB is also provided by the R&S FSH.
Press the UNIT softkey.
The units submenu then opens.
Using the rotary knob or the cursor keys select the
appropriate unit.
Confirm with the ENTER key or the UNIT softkey.
If the unit dB REL... has been selected, the reference
level value entry box opens.
Enter the reference level (REFERENCE) with the
number keys and terminate entry with the
appropriate unit or change the reference level
using the rotary knob or cursor keys.
The current level reading can be made the reference level by just pressing the ->REF softkey.
Press the ->REF softkey.
The R&S FSH sets the current measured level as the
reference level and from then on displays the
measured level relative to the reference level in dB.
The unit (UNIT) is automatically set to dB REL... .
The reference level is shown in the top left-hand corner
of the screen.
In the REFERENCE value entry box, the reference
level can be adjusted with the rotary knob or the cursor
keys or corrected by making a numeric entry.
Confirm the reference level with the ENTER key or
by pressing the ->REF softkey.
Setting the averaging time
The averaging time determines how long the signal will be measured for. The longer the averaging
time, the more stable the display – particularly if signals are at the lower end of the measurement range
or are noisy. The R&S FSH has three times for power measurements: short, normal and long.
Stationary sine signals with a high level (> -40 dBm) require only a short measurement time to produce
a stabile, accurate result. In this case, the FAST operating mode is recommended to obtain a high
repetition rate for the measurement. When the NORMAL setting is selected, the stability of the display
is increased for signals with low levels or for modulated signals. The LONG mode is recommended for
signals at the lower end of the measurement range (<-50 dBm to <-60 dBm). The R&S FSH-Z1
averages out the noise most effectively and the effect of noise on the measurement is minimal.
Press the MEAS TIME softkey.
To Next Page
Loading...
