GLIDE SLOPE DDM PERFORMANCE TEST.

TM 11-6625-2975-40

LOC DDM PERFORMANCE TEST. (CONT)

2-11.

41.

Extinguish 150 Hz TONE SELECT key, 90 Hz TONE SELECT key is lit.

Record differential voltmeter indication.

42.

Extinguish 90 Hz TONE SELECT key and press (to light) 150 Hz TONE SELECT key.

43.

Record differential voltmeter indication.

44.

45.

Divide recorded value in step 42 by value recorded in step 44. Resulting voltage ratio

should be

between 1.25861 and 1.26116. If not, go to troubleshooting chart 2-1, sh 9.

46. Repeat steps 20 through 24.

47. Divide recorded value in step 22 by value recorded in step 24. Resulting voltage ratio

should be

between 1.60417 and 1.60756. If not, go to troubleshooting chart 2-1, sh 9.

4 8 . Repeat steps 26 through 30.

49. Divide recorded value in step 28 by value recorded in step 30. Resulting voltage ratio

should be

between 2.26264 and 2.26797. If not, go to troubleshooting chart 2-1, sh 9.

50. Repeat steps 32 through 36.

51. Divide recorded value in step 34 by value recorded in step 36. Resulting voltage ratio

should be

between 2.99600 and 3.00400. If not, go to troubleshooting chart 2-1, sh 9.

GLIDE SLOPE DDM PERFORMANCE TEST.

Decade Resistor, Windslow 336

TEST EQUIPMENT REQUIRED:

Differential Voltmeter, Fluke 887AB/AN

RF Cables, RG-58/U with BNC plug-to-double banana plug termina-

tions and RG-58/U with double banana plug terminations

EQUIPMENT SETUP: Connect test set to 115 vac power source.

Connect differential voltmeter to test set as indicated in the following diagram.

EL9LY019

Turn on test set. Allow at least 30 minutes for warmup.