BIRD 428B-83H-01-C-110, Инструкция по установке и эксплуатации

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TX RX Systems Inc. Manual 7-9487-3 05/05/11 Page 10
base and tower top CPU’s. The modem assembly
is also used to inject the +12 VDC onto the main
transmission line that is required to power the
tower box circuitry.
RF signals leave the modem assembly and are
routed to a filter/attenuation assembly where they
pass through a wideband ceramic filter located in
the input circuit of the assembly. Following the filter
is a variable attenuator which allows adjustment of
the channels Reserve Gain attenuation. Signals
leave the filter/attenuation assembly and are sent
to the RF Output connector on the back of the deck
where they are available for the GTR-8000 system.
UNPACKING
Each major component of the TTA system is indi-
vidually packaged and shipped via motor freight or
UPS. It is important to report any visible damage to
the carrier immediately. It is the customer's respon-
sibility to file damage claims with the carrier within
a short period of time after delivery (1 to 5 days).
PRE-INSTALLATION CHECKOUT
The following pre-installation tests should be per-
formed after unpacking the system to verify nothing
has loosened during transit. Additionally, the sys-
tem should be made operational on the bench with
all components at ground level to verify proper
electrical performance.
Figure 9 illustrates all of
the cable connection points for both the tower top
box and the MCU and CMU base control units.
The tower top box should NOT be
installed on the tower until all of the
pre-installation tests are successfully
completed.
Mechanical Inspection
Open the tower top box by loosening the door
clamps and removing the two corner hold-down
screws. Make sure that all of the connectors inside
the box are tight. In addition, it is advisable to
check the tightness of the hold-down screws for the
various assemblies to insure nothing loosened dur-
ing shipment. It is important to re-tighten the tower
box door correctly so that the door gasket seal is
maintained. Insure that the moisture vent holes at
the bottom of the box are unobstructed. Likewise,
check all of the cable connections on the base con-
trol unit to insure that they are all properly mated to
their associated plugs.
CAUTION : The wide band filter in
the tower top box is factory tuned
and must not be field adjusted. Field
tuning of this filter is not required. Do
not adjust the tuning slugs of the
amplifier/filter assembly.
Initial Power-Up Test
To perform the initial power-up test the system
should be temporarily interconnected at ground
level using shor t temporary cables.
Figure 10
shows the temporary equipment hookup for initial
power-up testing of the MCU. Hook-ups for the
CMU are similar (test to test and main to main).
NOTE
Test
Test
Front Panel
Test Port
Main
Main
Tower Top Box
MCU
Figure 10: Initial power-up test.
MCU style base control unit shown as example.