HP HP 8566B, Руководство по настройке

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14. 100 MHz VCXO Adjustments
TRACE A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CLEAR-WRITE
TRACE B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BLANK
8. Adjust 100 MHz slowly through its full range while
monitoring the display of the second spectrum analyzer. The
output of the 100 MHz VCXO should be a single output signal
near 100 MHz,
with no spurious oscillations at other frequencies.
If spurious oscillations are present, increase the value of
factoryselected component
by one standard value and
check again for spurious oscillations. Refer to 3-3 for the
acceptable range of values, and to Table 3-4 for HP part numbers;
refer to Figure 3-65 for the location of
9. Disconnect the second spectrum analyzer from 100 MHz
OUT, and connect the frequency counter to
10. Adjust 100 MHz for a frequency counter indication of
100.0000 MHz Hz).
11. Disconnect the dc power supply from the TUNE test
point, and jumper TUNE to ground.
12. Verify that the frequency counter indication is less than 100.0000
MHz. If it is not, repeat, steps 3 through 11.
13. Disconnect, the jumper from TUNE and ground. Set the
dc power supply for an output of -25 Vdc, and connect the -25
Vdc output of the dc power supply to
TUNE.
14. Verify that the frequency counter indication is greater than
100.0000 MHz. If it is not, repeat steps 3 through 13.
15. Disconnect the dc power supply from TUNE, and
reconnect the cable 83 (gray/orange) to 100 MHz OUT.
16. Disconnect the cable 96 (white/blue) from 400 MHz IN,
and connect this cable to the RF INPUT of the second spectrum
analyzer using a BNC-to-SMB snap-on test cable and an SMB
male-to-male adapter.
17. Set the controls of the second spectrum analyzer as follows:
CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MHz
FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -7
RES BW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AUTO
LOG SCALE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 dB/div
TRACE A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CLEAR-WRITE
18. The 400 MHz output signal should be visible on the display of
the second spectrum analyzer, along with other harmonics of
100 MHz. Adjust the and 400 MHz
adjustments in sequence to maximize the power level of the 400
MHz output signal and minimize all other harmonics of 100 MHz.
Be sure to perform the adjustments in the proper sequence; it
might be necessary to repeat the sequence more than once.
19. Note the level of any 100 MHz harmonics displayed on the second
spectrum analyzer relative to the power level of the 400 MHz
Adjustments 3-129