HP 8340B Manual page 235

5-5.
20/30 LOOP PHASE LOCK, A36,
A3Q,
A39, A40, AND A43 (Cont'd)
29. Set the
DUT
as follows:
a.
Press INSTR
PRESET]
b.
Press
[START FREQ]
then enter
[2] [0] (MHz]
c.
Press
[STOP
FREQ] then enter [2] [5]
[MHz]
d.
Press
[SHIFT],
then [XTAL]
e.
Press
[SINGLE] Sweep
30. Adjust
A43R27 (5 MHz AF) to center the signal on the Spectrum Analyzer screen.
31. Disconnect the Spectrum Analyzer from
A36J1 and
reconnect
W39 to A36J1
(OUT 20-30 MHz).
PHASE LOCK LOOP 3
32. Set the LINE switch
to
STANDBY.
Remove A39 (PLL3 Up Converter) and install it
on an extender
board.
33.
Set
the
LINE switch to ON. Press [INSTR PRESET]. Press
[CW]
then
enter [5] [GHz]. Press
[SHIFT] [M3] to display the PLL2 and PLL3 frequencies.
34. Connect the Spectrum Analyzer to the Test Connector A39J3
on the P.C. board.
Tune the
Spec¬
trum Analyzer center frequency to 160
MHz.
Set the reference level to
-20 dBm and set the scale
to 1
dB per
division.
35. Adjust A39L16, A39L17, and A39C50 (160
MHz
PEAK) for maximum signal
level at
160
MHz.
Iteration
of
L16 and L17
adjustment may
be
necessary. Refer to Figure
5-11 for location of
adjust¬
ments.
If
A39C50
does
not have sufficient
range, select the value of A39C49 for proper range. (Refer
to
Table 5-2.)
36. At the DUT, select the following:
a.
Press [CF] then enter [6] [.] [6] [2] [7] [2] [5] [0] [GHz].
b.
Press
[AF] then enter [1] [0] [0] [kHz].
c.
Press
[SINGLE] Sweep
37. Tune the Spectrum Analyzer to
a center frequency
of
6
MHz. Set
the scale to 10 dB per division.
38.
The
6
MHz signal displayed should be at
least —42 dBm.
If
not,
repeat Steps 33
through 37.
39. Connect the
DVM to A39TP3.
40.
Adjust A39L11 (PLL3 VCO ADJ)
for
a
DVM
indication of
-7.5
Vdc
±0.1
Vdc.
The
voltage may not
change
with initial adjustment but will
change once the phase lock loop locks.
41. Press
[CF]
on the
DUT
then enter
[5] [GHz]. Press [SINGLE] SWEEP
to
initiate
a
sweep.
42.
The DVM
indication should be
-6.7
Vdc
±0.5 Vdc.
43.
Set
the LINE switch to
STANDBY. Disconnect the test
equipment
and reinstall A39 (PLL3 UP
Converter) in the
instrument.
PHASE LOCK LOOP
1
44.
Set the
LINE
switch to STANDBY.
Place A36 (PLL1 VCO) on
an extender board. Remove
all
cables
connected to A36.
HP 8340B/41B
Adjustments 5-31