Agilent Technologies N5242A Service Manual page 47

PNA Series Microwave Network Analyzers
N5242A
Cable Magnitude and Phase Stability Check
1. With the test port cable still connected to Port 1, connect a short to the other end of the
cable.
2. Press UTILITY
Preset
3. Press TRACE/CHANNEL
click the S11 box, and then click OK.
4. Press RESPONSE
5. Press RESPONSE
softkey to toggle it ON.
Average on/OFF
The Averaging Factor box will appear directly above the display. In the Averaging
Factor box, type 50 or click the arrows to select 50, and then press ENTRY
6. To provide a good reference, hold the test cable in a straight line perpendicular to the
front panel of the network analyzer.
7. Press RESPONSE
8. Wait for the analyzer to average the measurement 50 times (approximately two
seconds).
9. To normalize the data trace: press MARKER/ANALYSIS
then , then
Data Math
10. Slowly make a 180 degree bend in the middle of the cable and hold it in that position.
11. For each trace: press RESPONSE
The Scale Per Division box will appear directly above the display. Set the Scale Per
Division for optimum viewing as shown in
12. Place a marker on the largest deflection that goes above the reference line and is
within the cable's specified frequency range. For a typical response of cable magnitude
and phase stability, see
13. Place a marker on the largest deflection that goes below the reference line and is
within the cable's specified frequency range.
In this S measurement, the displayed trace results from energy being propagated
11
down the cable and reflected back from the short. Therefore, the measured deflection
value must be divided in half to reach the correct value.
Service Guide N5242-90001
.
Traces , then
, then
Format Phase
Average ON/off
Avg . Verify that
, then
Avg Averaging Restart
, then ENTRY
Data/Memory
Scale
Figure 3-6.
. In the New Trace dialog box,
New Trace...
, then ENTRY
Enter
is ON. If not, press the
.
Memory
.
Enter
, then .
Scale
Figure 3-6.
Tests and Adjustments
Preliminary Checks
.
.
Enter
, then
Data Trace
3-15
,