©1999 Navia Aviation AS Table of contents
TRANSMITTER DESCRIPTIONNORMARC 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
