NORMARC NM 7000 Series, Инструкция по установке и пусконаладке

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The hybrid port 4 is terminated in 50
Ω
, min. 5 watts dummy load. Port 2 is connected to a
directional coupler which is terminated in 50
Ω
, min. 5 watts dummy load. The directional cou-
pler forward port is connected to NM3710 Field Test Set. Use 20 dB attenuator at the BNC I/P
of NM3710.
The NM3710 DDM should be 0.0%. If necessary adjust the SBO phaser of associated trans-
mitter in the Cabinet to 0.0% DDM. Carry out the same procedure for the other transmitter.
6.3.2 Sector Width adjustment
Figure 6-4 test set-up is used. Remove the 90°-stub.
The NM3710 DDM should be 23.4%. If necessary adjust the SBO attenuator of associated
transmitter in the Cabinet to obtain 23.4% DDM. Carry out the same procedure for the other
transmitter.
127(
7RFRPSHQVDWHIRUDVORSLQJWHUUDLQLQIURQWRIWKH*3WKH''0DFFRUGLQJO\VKRXOGEH
where
θ
0
is the glide path angle
FSL is forward slope, negative sign for falling terrain referred from the GP
.
Figure 6-4 Measurement set-up for CSB/SBO phasing and Sector Width adjustment.
DDM
11.7
θ
0
FSL –
( )
θ
0
--------------------------------------
=
1
2
3
4
0°
0° 0°
180°
180° HYBRID
50Ω 50Ω
CSB
SBO 20dB NM3710
FIELD TEST SET