TB 9-6625-1932-24
EXAMPLE A: If first test frequency recorded in (48) above is 27 GHz:
RF = 27 / 3
RF =9 or 9 GHz
required for the desired measurement by calculating the following equation:
LO = ((3 X RF)-IF) / 2
EXAMPLE B:
Where:
RF =
Signal generator frequency in GHz recorded in (49) above
IF =
1 (operating frequency of receiver system in GHz)
LO =
Programmable sweep generator frequency
LO =
((3 X 9) -1) / 2
LO =
(27 - 1) / 2
LO =
26 / 2
LO =
13 or 13 GHz
above and RF output controls for +3 dBm.
(52) Adjust programmable sweep generator frequency controls to value determined in
(50) above and LEVEL output controls for +3 dBm.
(53) Establish a 0.00 dB reference on receiver system at 1 GHz.
NOTE
Ensure receiver system is in measurement mode.
(54) Disconnect fixed short from directional coupler No. 4 (fig. 6).
(55) Zero power meter No. 1 and connect TI to directional coupler No. 4, point A (fig.
6). Record receiver system indication as return loss.
(56) Remove TI from directional coupler No. 4 and connect fixed short to directional
coupler No. 4, point A (fig. 6).
(57) Repeat technique of (53) through (56) above two more times and average values
recorded in (55) above. Determine VSWR using Appendix B. VSWR will be within the
limits listed in Appendix A.
(58) Repeat (49) through (58) for remaining cardinal test point frequencies recorded
in (48) above.
b. Adjustments (Hewlett-Packard, Models 478A and 8478B only)
CAUTION
Use extreme care when making A adjustments (fig. 7) in the cw
direction. Over adjustment will damage TI.
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