Cable Measurements
R&S FSH
1145.5973.12 4.122
E-14
When calibration is over, the R&S FSH displays
DTF CAL in the upper right-hand corner of the screen.
The REFLECT CAL softkey label is highlighted in
green to indicate that calibration has been successfully
completed.
The trace displays cable reflections versus distance
from the measurement plane.
Note to Calibration:
Calibration is performed over the entire R&S FSH frequency range. This eliminates the need for
recalibration when a different cable length is selected. The calibration data are saved in the R&S FSH's
internal memory so that calibration remains effective when switchover is made to another operating
mode or the instrument is switched off. As a precondition for calibration to remain valid, however, the
instrument temperature must not change by more than 5 °C after calibration. If the temperature
changes by more than 5 °C, a red circle is placed ahead of DTF CAL to indicate that there is a risk of
increased measurement error. In such a case, it is advisable to recalibrate the test setup.
Unscrew the SHORT from the measurement cable.
Screw the cable under test to the measurement cable.
The R&S FSH displays the reflections produced in the
cable under test. The measurement diagram on the
right shows a cable that is approximately 15 m long
and fitted with a connector 5 m from the start. The end
of the cable is terminated with a 3 dB attenuator pad.
The R&S FSH shows that the return loss of the
reflection from the termination at the end of the cable
(approx. 157 m) is approx. 7 dB. The connector, for
example, is the 20 dB peak at 5 m. On the extreme left
of the trace, the matching of the connection to the
cable under test can be seen.
深圳市盛腾仪器仪表有限公司
Tel:0755-83589391
Fax:0755-83539691
Website: www.Sengt.com