16. YTO Loop Adjustments
Figure 3-72.
Typical YTO Loop Swept Frequency Response at
21. On the second spectrum analyzer, key in
[
PEAK SEARCH
)
to position
a marker on the peak of the TRACE A displayed signal. Press
PEAK
]
on the second spectrum analyzer and wait for the
preselector peaking routine to complete.
22. On the Spectrum Analyzer (DUT), key in
and wait for
the sweep to complete (200 seconds) and the SWEEP LED to turn
Off.
23. On the Spectrum Analyzer (DUT), key in
5,
[
CENTER FREQUENCY
).
Use the DATA knob to tune the
YTO
to position the TRACE A signal at the lowest point on the TRACE
B waveform on the display of the second spectrum analyzer, as
shown in Figure 3-72.
24. Repeat steps 21 through 23 as necessary until the lowest point in
the TRACE B waveform does not change.
25. On the spectrum analyzer (DUT), key in
REF
to activate the Frequency Diagnostics function. Six lines of
numerical data should appear in the upper left corner of the
spectrum analyzer CRT; the top line is the 10 digit YTO Start
Frequency, ranging from 2.000 000 000
to 6.200 000 000
Note the currently-selected YTO Start Frequency (the minimum
power frequency of the All YTO Loop). This frequency should be
approximately the same as the marker frequency displayed on the
second spectrum analyzer.
All YTO Loop Minimum Power Frequency:
26. Disconnect the low-loss microwave test cable from the SMA
female end of
and from the RF INPUT of the second
spectrum analyzer.
27. Connect the power sensor to the power meter’s POWER REF
output, and zero and calibrate the power meter. Determine the
power sensor cal factor for the Al 1 YTO Loop Minimum Power
Adjustments 3-139
