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 11
Once the equipment is temporarily interconnected
then power is applied to the system by plugging the
control unit’s AC cord into a suitable AC outlet
(models 428B-83H-01-M-110 and 428B-83H-01-C-
110) or by connecting the DC power cable to a suit-
able -48 VDC supply (model 428B-83H-01-M-48
and 428B-83H-01-C-48). The following start-up
sequence occurs.
1) At turn-on, the three front panel status LED’s
will all glow a steady red while the display panel
shows a row of solid boxes on the top display
line. This will last for about 10 seconds while
the systems micro-controllers boot-up.
2) During the next 5 seconds the base control unit
will establish communications with the tower
box. The front panel status LED’s will occasion-
ally flash green. The display panel will present
the message “Connecting to Tower Controller”
and then will briefly flash the base control unit’s
current software version. See
Figure 11 .
3) After the power-up sequencing is complete the
screen should show the default display as
shown in
Figure 12 . The status LED for each
active amplifier will glow a steady green and the
status LED for the inactive (stand-by) LNA will
be dark.
The tower top amplifier system is software directed
so control of the system is accomplished via user
interface with the front panel using the display
screen and the four menu selection buttons. A flow
chart showing all of the possible user menu selec-
tions is shown in
Figure 13 .
Bench Testing
The purpose of the bench test is to verify that all of
the system components are working correctly and
to measure the systems sensitivity before climbing
the tower to mount the tower top box. One station
receiver is selected and the test is performed at
this frequency. Short temporary cables are used to
interconnect all components. A SINAD meter is
used for the test (or a bit error rate meter if
required) along with a signal generator.
1) The stand-alone receiver sensitivity is mea-
sured and recorded first. Record the value in
Table 5 .
2) Connect the equipment as shown in Figures 14
or 15 . Be sure that the signal generator is setup
for a 3 KHz deviation with a 1000 Hz tone (ana-
log) or proper pattern for BER testing.
3) Measure and record the systems bench test
static sensitivity in table 5. The sensitivity value
will vary depending on the amount of internal
programmable attenuation selected via soft-
ware interface. The bench test measurement
should be taken with the default values selected
Test Performed Result
Stand Alone
Receiver
Sensitivity dBm
* Bench Test
Static
Sensitivity dBm
Model Number
(Tower Top Box)
Serial Number
(Tower Top Box)
Table 5 : Bench Test Results.
* Default Reserve Gain Attenuation (3.0 dB)
* Default Distribution Attenuation (1.0 dB)
Figure 12: Default display.
Figure 11: Base Control Unit software version is dis-
played briefly during the boot-up sequence.