TB 9-4931-534-35
(10) Divide value record value recorded in (6) above by 2. Invert sign and subtract
from value recorded in (7) above. Record difference as return loss:
EXAMPLE B: If value of (6) above is +1.425
Divide +1.425 by 2
(a)
+1.425 2 = +0.712
Invert sign of +0.712 = -0.712
(b)
Subtract -0.712 from value recorded in (7) above. (Let value recorded
(c)
in (7) above be 10.741.)
10.741 (7) above
-0.712
10.029 return loss
(11) Remove TI from VSWR bridge and connect short to VSWR bridge.
(12) Adjust synthesized signal generator RF output level to reference established
on receiver system in (4) above.
(13) Repeat technique of (6) through (12) above two times and average values.
Averaged value in dB will be within the limits as listed in Appendix A.
(14) Repeat (11) above.
point listed in 7 a above and RF output level to reference established on receiver system in
(4) above.
(16) Repeat (6) through (15) above for remaining frequencies recorded in 7 a above.
b. Adjustments. No adjustments can be made; however, a correction chart may be
prepared showing actual VSWR values at test frequencies.
9. VSWR,
Waveguide Mismatches, and
Terminations (to 18 GHz)
a. Performance Check
(1) Connect equipment as shown in figure 2 and allow equipment to warm-up for 1
hour.