HP 8568B, Performance Tests And Adjustments Manual, Page: 239 / 313

19. Second Converter Adjustments
9. Readjust MIXER for maximum power
indication.
10. Disconnect the amplifier’s input from and connect to
11. Adjust PILOT MIXER for maximum power
meter indication. See Figure 3-73 for location of adjustment.
12. Disconnect power meter and connect frequency counter to
amplifier’s output.
13. Key in [SHIFT) to shift Second LO up and to shift
Second LO down.
14. Continue to shift Second LO up and down while adjusting
LO SHIFT for a frequency difference of 5.0
MHz fO.l MHz. Ignore the absolute value of either frequency.
Clockwise rotation of
decreases the frequency
difference.
15. Key in (SHIFT) (Second LO shifted down).
16. Adjust LO FREQ for frequency counter
indication of 1748.6 MHz fO.l MHz.
17. Repeat steps 13 through 16 until specifications of steps 14 and 16
are achieved.
18. Disconnect frequency counter and connect power meter to the
amplifier’s output.
19. Shift Second LO up and down, using and (SHIFT)
while adjusting PILOT MIXER for equal
power out in both states of Second LO.
20. Power difference between Second LO shifted up and shifted down
should be less than 0.5
21. Disconnect amplifier’s input from and connect to
22. Shift Second LO up and down, using and
while adjusting MIXER for equal power out
in both states of the Second LO.
23. Power differences between Second LO shifted up and shifted
down should be less than 0.5
24. Disconnect power meter and connect frequency counter to
amplifier’s output.
25. Key in
Note frequency counter indication. If
necessary, readjust LO FREQ for frequency
counter indication of 1748.6 fO.l MHz.
26. Shift Second LO up and down, using and
and note frequency difference between low and high state
of Second LO. If necessary, readjust LO SHIFT
for a frequency difference of 5.0 MHz fO.l. Repeat
steps 27 and 28 until specifications contained in each step are
achieved.
Adjustments 3-125