NORMARC 7033, Manual

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©1999 Navia Aviation AS Table of contents
TRANSMITTER DESCRIPTION NORMARC 7033
INSTRUMENT LANDING SYSTEM
iii
TABLE OF CONTENTS
1 FUNCTIONAL DESCRIPTION ........................................................................9
2 DETAILED DESCRIPTION..............................................................................11
2.1 Transmitter block diagrams ................................................................................ 11
2.2 LF1223A Low Frequency Generator .................................................................. 14
2.2.1 NMP110A Low Frequency Generator Control ............................................. 14
2.3 OS1221B RF Oscillator ...................................................................................... 15
2.4 GPA1231A Glidepath Course Power Amplifier Assembly.................................. 17
2.4.1 GPA1232A Glidepath Clearance Power Amplifier Assembly ...................... 19
2.4.2 PA1234A Power Amplifier ........................................................................... 20
2.4.3 AC1226A Amplitude control......................................................................... 21
2.4.4 PC1225B Phase Control.............................................................................. 21
2.4.5 FD1236A Feedback Detector ...................................................................... 21
2.4.6 CD1238A Combiner Detector ...................................................................... 23
2.5 COA1207C Change-Over Assembly.................................................................. 23
3 TESTS AND ADJUSTMENTS .........................................................................25
3.1 Transmitter Alignments and Calibration ............................................................. 25
3.1.1 RF Phase Feedback Adjustment ................................................................. 25
3.1.2 RF Power ..................................................................................................... 25
3.1.3 LF Phase Adjustment .................................................................................. 26
3.1.4 RF Power Balance Adjustment .................................................................... 27
3.1.5 RF Phase at Combiner I/P ........................................................................... 28
3.1.6 SDM Calibration........................................................................................... 29
3.1.7 DDM Calibration .......................................................................................... 29
3.1.8 Ident Tone Modulation Depth ...................................................................... 29
3.1.9 RF Frequency Adjustment ........................................................................... 30
3.2 Antenna System Adjustments ............................................................................ 30
3.3 Adjustment points............................................................................................... 31
3.4 Frequency configuration strap settings .............................................................. 33