Thales 421 - Setting of Transmitter and Antenna

LLZ 421
Operation and Maintenance Alignment Procedure LLZ−2F (LPD)
ILS 420
8−9Ed. 07.08
SOAC
8.3 SETTING OF TRANSMITTER AND ANTENNA
NOTE: Because two different PC user programs (ADRACS and MCS) can be used, the user pro-
gram−specific actions/procedures are described in detail in the ANNEX ’PC User Pro-
gram−specific Procedures’.
8.3.1 Adjusting CRS CSB Signal
a) Switch both TX on and set TX1 on aerial.
b) Open dialog ’Transmitter1−Waveform Data#1’, open dialog ’Transmitter2−Waveform Data#1’.
c) Set parameter ’CRS CSB RF−Level’ of both TX to 15 W.
d) Set parameter ’CRS CSB SDM’ of both TX to 40 %.
e) Set parameter ’CRS CSB DDM’ of both TX to 0 %.
f) Set parameters ’CLR CSB RF−Level’ and ’CLR SBO Amplitude’ of both TX to 0 W and ’CRS SBO
Amplitude’ of both TX to 0 %.
g) Measure SDM and DDM of CSB course signal for TX1 with the portable DDM instrument in the
radiation field at the measurement circle (close to the course line) or use RF signal from nearfield
dipole and connect it to portable instrument. If necessary, correct SDM and DDM of TX1 to get an
indication of 40.0 % SDM and 0.0 % DDM.
h) Open dialog ’Transmitter1−Waveform Data#1’, open dialog ’Transmitter2−Waveform Data#1’.
Set ’Ident AM’ for both TX e.g. to 10 %
. Use portable instrument. Check if IDENT is measured by
execut. monitors.
i) Set TX2 on aerial. Perform the same procedure as for TX1 in step g) and h).
j) Switch both TX off.
8.3.2 Adjusting CLR CSB Signal
a) Switch both TX on and set TX1 on aerial.
b) Open dialog ’Transmitter1−Waveform Data#1’, open dialog ’Transmitter2−Waveform Data#1’.
c) Set parameter ’CLR CSB RF−Level’ of both TX to 7.5 W.
d) Set parameter ’CLR CSB SDM’ of both TX to 40 %.
e) Set parameter ’CLR CSB DDM’ of both TX to 0 %.
f) Set parameters ’CRS CSB RF−Level’ and ’CRS SBO Amplitude’ of both TX to 0 W and ’CLR SBO
Amplitude’ of both TX to 0 %.
g) Measure SDM and DDM of CSB clearance signal for TX1 with the portable DDM instrument in the
radiation field at the measurement circle (approximately at an angle of 15°). If necessary, correct
SDM and DDM of TX1 to get an indication of 40.0 % SDM and 0.0 % DDM.
h) Set TX2 on aerial. Perform the same procedure as for TX1 in step g).
i) Switch both TX off.
8.3.3 Set CSB/SBO Phase (Course)
a) Switch both TX on and set TX1 on aerial.
b) Open dialog ’Transmitter1−Waveform Data#1’, open dialog ’Transmitter2−Waveform Data#1’.