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9. Readjust A23A3 2ND MIXER A23A3Z4 for maximum power
indication.
10. Disconnect the amplifier's input from A23A3J3 and connect to
11. Adjust A23A3 PILOT 2ND MIXER A23A3Z8 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) @) u to shift Second LO up and ISHIFT) a T to shift
Second LO down.
14. Continue to shift Second LO up and down while adjusting A23A3
MHz fO.l MHz. Ignore the absolute value of either frequency.
Clockwise rotation of A23A3ZlO decreases the frequency
difference.
15. Key in (SHIFT) a T (Second LO shifted down).
16. Adjust A23A3 2ND LO FREQ A23A3Z9 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 m m u and (SHIFT) a
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 dB.
21. Disconnect amplifier's input from A23A3J4 and connect to
22. Shift Second LO up and down, using (SHIFTY a u and ISHIFT) @) T
while adjusting A23A3 2ND MIXER A23A3Z4 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 dB.
24. Disconnect power meter and connect frequency counter to
amplifier's output.
25. Key in [SHIFT) a T. Note frequency counter indication. If
necessary, readjust A23A3 2ND LO FREQ A23A3Z9 for frequency
counter indication of 1748.6 fO.l MHz.
26. Shift Second LO up and down, using ISHIFT) @) ' and ISHIFT) a
of Second LO. If necessary, readjust A23A3 2ND LO SHIFT
steps 27 and 28 until specifications contained in each step are
achieved.
19. Second Converter Adjustments
Adjustments 3-125
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