R&S FSH
Working with Power Sensors
Using a Power Sensor
Operating Manual 1309.6275.12 - 14
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Alternatively, you can set the current level readout as the reference level.
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Press the " Ref" softkey.
The R&S FSH sets the current result as the reference level.
It then displays the measured level relative to the reference level in dB. The unit is
automatically set to dB Rel...
Setting the averaging time
The averaging time determines the length of the measurement. The longer the
averaging time, the more stable the display, particularly if signals have low power or
are noisy.
The averaging time is either "Short", "Normal" or "Long".
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A short measurement time provides stable and accurate results for stationary sine
signals with high levels (> -40 dBm). It is also appropriate for measurements that
require a high repition rate.
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A normal measurement time increases the stability of results for signals with low
levels or modulated signals.
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A long measurement time is appropriate for signals with very low power levels
(< -50 dBm)
To eliminate noise and the effects of noise on the measurement effectively, use the
R&S FSH-Z1 power sensor.
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Press the "Meas Time" softkey.
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Select the measurement time most suitable for your test setup.
Taking additional loss or gain into account
At high powers that cause the power sensor maximum input level to be exceeded or at
very low levels that are below the R&S FSH minimum sensitivity, the R&S FSH can
take additional loss or gain between the DUT and the power sensor into account.
These are defined in terms of an offset in dB relative to the measured level. A positive
offset corresponds to a loss and a negative offset to a gain.
The R&S FSH shows the current offset in the diagram header.
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Press the AMPT key.
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Press the "Ref Offset" softkey.
The value entry box for the reference offset opens.
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Enter the required offset.
The offset is taken into account in the power or level display.
