Installation Instructions

Table Of Contents
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10.2.2 Monitor return cable length
Measure return phase as described in (8.2.1) for both monitor cables. Check that initial val-
ues are within ±1.5° true phase (±3.0° return phase).
10.2.3 Phase and amplitude transfer measurement
Connect each antenna cable and monitor cable to LPDA load and source respectively. Utilise
a vector voltmeter or network analyser in a test set-up
Figure 10-2, and measure relative transfer phase and amplitude for the antenna cable (A2) in
reference to antenna (A1)
.
Figure 10-2 Phase and amplitude transfer measurement set-up.
Measure and record phase/amplitude for each antenna. Then determine if one of the monitor
cables must be trimmed in order to comply with phase tolerance for the set of cables.
Tolerance: ±3°.
Amplitude tolerance: ±1.0 dB. If the amplitude tolerance is exceeded something might be
wrong in the LPDA monitor circuit or connector/cable.
20dB
AB
VECTOR VOLTMETER
A(n)
M(n)
LPDA
DIR. COUPL.
From Marker
Dir. coupler