17.
Loop Phase Lock Adjustments
1. Set the RF Section LINE switch to STANDBY. Remove
2.
3.
4.
PLL3 Up Converter Assembly from the RF Section, and install it
on an extender board. Reconnect the cable 7 (violet) to
SCAN
MHz OUT and the cable 8 (gray) to
IN 100
MHz.
Connect the RF INPUT of the second spectrum analyzer to SMB
test connector
Refer to Figure 3-80 for the location of
test connector
U P
C O N V E R T E R
TOP VIEW
Figure
Location of
Adjustments
Set the RF Section LINE switch to ON, and key in
SPAN
)
0
HZ
.
On the second spectrum analyzer, key in
Set the controls of the second spectrum analyzer
as follows:
CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 MHz
FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
RES BW (MANUAL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . -20
In addition to the displayed 160 MHz signal, other signals should be
present at
at approximately 160.3 MHz and 300
5. On the second spectrum analyzer, key in MARKER
(
PEAK SEARCH
),
MKR
REF
to position the peak of the displayed 160 MHz
signal at the top CRT graticule line. Then, key in
[
ENTER
2
[
FREQUENCY SPAN
)
50
STEP
on the second spectrum analyzer to lower the peak of the
displayed signal by three major graticule divisions.
3-156 Adjustments
