Thales 421 - Clearance Width Monitor

LLZ 421
Operation and Maintenance Alignment Procedure LLZ−2F (LPD)
ILS 420
8−17Ed. 07.08
SOAC
d) Send to Monitor1/2 the command ’Calibration, Executive CRS Width detector’.
e) Restore TX1 SBO settings of 8.4.3.2 c) back to normal.
f) Check and set DDM indication to 15.5 % with R383.
NOTE: The procedure enables to calibrate to 15.5 % within a range of about 15 % to 16 %. This is nor-
mally achieved by an accurate adjustment.
g) Send to Monitor1/2 the command ’Calibration, Executive CRS Width detector’.
8.4.3.3 Clearance Width Monitor
a) RF−level of the corresponding path on the SOAC (Fig. 8−2, 8−3) is set to amplitude of 3.6 Vpp
as described in 8.4.1.
b) Measure DDM with the field receiver. Note down value (used in 8.4.4.3).
c) Open dialog ’Monitor1−Nominal Values’ and open dialog ’Monitor2−Nominal Values’. Enter the
measured values for ’EXEC CLR Width DDM’ and ’EXEC CLR Width SDM’.
d) Open dialog ’Transmitter1−Waveform Data#1’. Note down the values of ’CLR SBO Amplitude’
and ’CRS SBO Amplitude’. Set them all to 0.
e) Send to Monitor1/2 the command ’Calibration, Executive CLR Width detector’.
f) Restore TX1 SBO settings of 8.4.3.3 d) back to normal.
g) Send to Monitor1/2 the command ’Normalization, Executive CLR Width detector’.
8.4.3.4 Adjustment of Position Nearfield Monitor, optional (if available)
a) Set the RF−level of the corresponding path on the SOAC (Fig. 8−2, 8−3) to amplitude of 3.6 Vpp
as described in 8.4.1.
b) Shift nearfield dipole position so that DDM 0.0 % is received. Measure DDM with field receiver.
c) Open dialog ’Monitor1−Nominal Values’ and open dialog ’Monitor2−Nominal Values’. Enter the
measured values for Nearfield DDM.
d) Open dialog ’Transmitter1−Waveform Data#1’. Note down the values of ’CRS SBO Amplitude’
and ’CLR SBO Amplitude’. Set them all to 0.
e) Send to Monitor1/2 the command ’Calibration, Executive Nearfield Pos. detector’ (or ’Executive
Ch. 4 Width detector’).
f) Restore TX1 SBO settings of 8.4.3.4 d) back to normal.
g) Send to Monitor1/2 the command ’Normalization, Executive Nearfield Pos. detector’ (or ’Executive
Ch. 4 Width detector’).