HP 8340b, Manual

Page: 146 / 234

5-5. 20/30 LOOP PHASE LOCK, A36, A38, A39, A40, AND A43 (Cont’d)
64. Connect the Spectrum Analyzer to A38J1 (OUT PLLi) IF. Set the Spectrum Analyzer controls as
follows:
INSTR PRESET
Press
CENTER FREQ i70
MHz
FREQ SPAN 200
kHz
RESBW 3kHz
VBW 3kHz
SWP
lOOms
REF LEVEL
lOdBm
ATT 0dB
SCALE/DIV 10 dB/DIV
MARKER NORMAL
65.
Disconnect the cable from
A36J2 (OUT 200 - 300
MHz) and connect the cable to the Signal
Generator using a BNC to SMB snap-on test cable and adapter.
66.
Adjust A38L1i (165 MHz NULL), A38Li2 (160 MHz NULL), and A38L13 (170
MHz NULL) fully
clockwise.
67.
Set the Signal Generator for an output of 330.3 MHz ±0.2MHz at 0 dBm.
68. Adjust A38L13 (170 MHz NULL) to null the 170 MHz signal on the Spectrum Analyzer.
69. Change the Signal Generator frequency to 325.3 MHz ±0.2MHz. Set the Spectrum Analyzer
CENTER FREQ
to 165 MHz.
70. Adjust A38L11 (165 MHz NULL) to null the 165 MHz signal on the Spectrum Analyzer.
7i. Change the Signal Generator frequency to 320.3 MHz
±0.2 MHz.
Set the Spectrum Analyzer
CENTER FREQ to 160 MHz.
72. Adjust A38L12 (160 MHz NULL) to null the 160 MHZ signal on the Spectrum Analyzer.
73. Set the Spectrum Analyzer CENTER FREQ to 140 MHz. Tune the Signal Generator to 300.3 MHz
±0.2MHz. Note the amplitude of the 140 MHz response on the Spectrum Analyzer.
74. Set the Spectrum Analyzer as follows:
INSTR PRESET Press
STARTFREQ 130MHz
STOP FREQ 170 MHz
MARKER NORMAL
MARKER frequency 140 MHz
Slowly tune the Signal Generator from 320.3 to 326.3 MHz while monitoring the display on the
Spectrum Analyzer.
75. The amplitude of the signal response between 160 and 166 (Signal Generator frequency of 320.3
to 326.3 MHz) should be at least 60 dB below the response at 140 MHz (Signal Generator fre-
quency of 300.3 MHz) noted in Step 73.
76. Set the LINE switch to STANDBY. Reinstall A38 (PLL1 IF) in the instrument and reconnect all the
cables.
HP 8340B/41B
Adjustments 5-35/5-36