TB 9-5985-314-35
FOR DIRECTIONAL COUPLERS (10MHZ TO 18GHZ)
NOTE
Software package USATA PD-MAT () can be used in place of
steps 1 a (1) through 1 a (35) below, verifying that the TI meets
or exceeds accuracies listed in Appendix A. Copies of the
software package are available from Commander, U. S. Army
Aviation and Missile Life Cycle Management Command,
ATTN: AMSAM-TMD-LW, Redstone Arsenal, AL 35898-5000
or on the USATA homepage.
a. Performance Check
NOTE
When performing the following steps if TI frequency range is
above and below 1.3 GHz it will be necessary to perform two
separate tests - one below and one above 1.3 GHz.
(1) Zero and calibrate power meter and measuring receiver RF power.
(2) Connect equipment as shown in figure 7 (Connect POINT A to POINT B).
Determine and record in table E-1 a minimum of 10 evenly spaced test frequencies over the
entire TI frequency range.
table E1 and
adjust signal generator No. 1
RF OUTPUT controls for +6
dBm.
NOTE
Use adapters as needed.
(4) Press 4.0 SPCL keys and, if the AUTO TUNING indicator light is off, press the
measuring receiver FREQ and BLUE (SHIFT) AUTO TUNING keys.
NOTE
For frequencies below 1.3 GHz proceed to step (8).
NOTE
For frequencies 1.3 GHz and above, proceed to step (5) below.
For frequencies above 1.3 GHZ, the offset frequency should be
120.53 MHz above that of signal generator No. 1.
(5) Enter the test frequency into the measuring receiver and press the MHz key.
(6) Calculate and record the proper offset frequency and record it as the Offset
Frequency in table E1 alongside the appropriate test frequency. Set signal generator No. 2
to produce a +8 dB output at offset frequency.