Figure 9-4. Waveguide Slotted Line Adjustment

T.O. 12P4-2APX-192

NAVAIR 16-35TS1843-1

TM 11-6625-1646-25

9. Slide detector probe to obtain minimum standing wave

9-15.

WAVEGUIDE SLOTTED LINE, MX-9052/APM-362

indicator SWR scale deflection.

ADJUSTMENT.

10. Adjust double stub tuner for standing wave indicator meter

9-16. The following procedure is to be used to adjust the

deflection approximately halfway between maximum and

waveguide slotted line used to check TS-1843A/ APX voltage

minimum deflection points.

standing wave ratio detector. Two adjustments are required.

11. Repeat steps 8 through 10 until difference between

One adjustment tunes the double stub tuner to obtain a

maximum and minimum deflection point is 1.03 or less. As

voltage standing wave ratio of 1.03 to 1 over the entire length

final check adjust standing wave indicator GAIN control until

of the slotted line. The second adjustment is to obtain

maximum deflection indication is at 1 on SWR scale. Slide

waveguide slotted line settings that produce mismatches of 7.5

detector probe; minimum deflection point should be 1.03 or

db and 10.5 db. Proceed as follows:

less on standing wave indicator SWR scale. Lock double stub

1. Make adjustment connections per figure 9-4. Do not insert

tuner.

waveguide slotted line at this time.

12. Insert waveguide slotted line into slotted line no. 2.

2. Turn on test equipment and allow adequate warmup time

13. Slide waveguide slotted line for maximum deflection on

per manufacturer's instructions.

standing wave indicator DB scale. Adjust standing wave

3. Adjust signal generator for output frequency of 1090 MHz

indicator GAIN control to obtain 0 on DB scale.

and internal modulation frequency of 1 KHz. Apply power to

14. Slide waveguide slotted line for minimum deflection on

signal generator; adjust modulation to 70% to 80%.

standing wave indicator DB scale. Adjust waveguide slotted

4. Place standing wave indicator controls in the following

line vernier to obtain approximately 7.5 DB indication on

positions:

standing wave indicator.

INPUT SELECTOR - 200 K

15. Repeat steps 13 and 14 until standing wave indicator

RANGE - 50

meter indications are 0 and 7.5 on DB scale as waveguide

METER SCALE - NORMAL

slotted line is moved along slotted line. Record waveguide

GAIN -

Adjust for approximate center scale meter

slotted line vernier setting as the setting that produces a 7.5

deflection.

db mismatch.

5. Move detector probe on slotted line no. 2 to right end of

16. Repeat steps 13 through 15 to obtain waveguide slotted

slotted line.

line vernier setting that produces a 10.5 db mismatch and

6. Adjust slotted line no. 1 detector probe to obtain the

record. Change RANGE scale to 60 to confirm 10.5 db

greater of two standing wave ratio deflections on standing

mismatch.

wave SWR scale.

17. Remove power from signal generator and standing wave

indicator.

Disconnect signal generator, standing wave

NOTE

indicator and slotted line no. 1 from double stub tuner.

Waveguide slotted line adjustment is complete.

The detector probe on waveguide slotted

line must be moved over 180 electrical

9-17. TS-1843A/APX ADJUSTMENT.

degrees as indicated on slotted line to obtain

maximum and minimum indications.

9-18.

Following replacement of the comparator-decoder

assembly (A4) or repair of the ringing oscillator circuit,

7. Slide detector probe to obtain maximum standing wave

adjustment of A4C6 must be accomplished. During A4C6

indication SWR scale deflection.

adjustment, the comparator-decoder assembly must be

8. Adjust standing wave indicator GAIN control to place meter

inserted into the TS-1843A/ APX and the side covers must be

indicator at convenient reference point on SWR scale. Note

in place. Perform A4C6 adjustment per table 9-3.

reference point.

Figure 9-4. Waveguide Slotted Line Adjustment

9-4