NORMARC NM 7000 Series, Инструкция по установке и пусконаладке

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7.3.2 CSB/SBO phasing
Insert the 90°-stub in the SBO cable path to the ADU. Connect the NM3710 Field Test Set to
the monitor return cable (M1) from the lower antenna.
Adjust SBO phaser in the Cabinet (associated with Tx to air) to obtain 0 DDM reading.
Repeat the phasing procedure for the second transmitter.
Remove the 90°-stub from the SBO path.
7.4 Sector width adjustment
7.4.1 SBO power adjustment
Connect the Field Test Set to the monitor return cable (M1) from the lower antenna.
Adjust the SBO step attenuator in the cabinet (associated with Tx to air) to obtain the pre-
scribed DDM value.
For a perfect flat terrain the DDM in A1 (M1) should be -11.7%.
127(
7RFRPSHQVDWHIRUDVORSLQJWHUUDLQLQIURQWRIWKH*3WKH''0DFFRUGLQJO\VKRXOGEH
where
θ
is the glide path angle
FSL is forward slope, negative for falling terrain referred from the GP.
Repeat the SBO attenuator adjustment for the second transmitter.
7.5 Monitor combining unit (MCU) adjustments
7.5.1 Procedure for horizontal terrain (FSL = 0°)
Connect the Field Test Set to the CL output of the MCU. Adjust the MCU phaser at A1 (lower
antenna) to read 0% DDM.
Remove the 90°-stub from the SBO path. Adjust the MCU attenuator at A1 to read 0% DDM at
the CL output.
Connect the Field Test Set to the DS output of the MCU. Read the DDM value. This should be
8.75% DDM unless a SBO power compensation for sloping foreground and K3, K4 cable
length compensation has been taken into account (See 1.5.2).
7.5.2 Procedure for sloping terrain (1° > FSL > -1°)
If the terrain in front of the GP is not horizontal, cable lengths K3 and K4 should be changed in
accordance with the table below:
DDM
11.7
θ
0
FSL –
( )
–
θ
0
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=