Bird Technologies 429-83H-01 Series-Manual - Manual (Page 14)

TX RX Systems Inc. Manual 7-9439-6 09/03/09 Page 6
3) After the power-up sequencing is complete the
screen should show the default display as
shown in Figure 6. 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 7.
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 4.
2) Connect the equipment as shown in Figure 8.
Be sure that the signal generator is setup for a 3
KHz deviation with a 1000 Hz tone (analog) or
proper pattern for BER testing.
3) Measure and record the systems bench test
static sensitivity in table 4. 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
for “TTA NET GAIN” attenuation (3.0 dB) and
“DISTRIBUTION” attenuation (1.0 dB). These
are the factory default settings that are pro-
grammed into your system when you first turn it
on.
4) Select the other tower top amplifier and check
that the bench test static sensitivity value
remains nearly the same. This will insure that
both amplifiers in the tower top box are func-
tioning properly. To select an alternate tower-
top amplifier press the associated amplifier
select button on the front panel, the status LED
will begin to flash, then press the ENTER button
to finalize the selection.
5) If the tower box door is opened during the
installation it is important to re-tighten the door-
clamp locking screws uniformly so that the door
gasket seal is maintained. Tighten each clamp
about half-way, then start back at the first clamp
and fully tighten each one in the same order.
Tighten with a hand tool only. Insure that the
moisture vent holes at the bottom of the box are
unobstructed.
Test Performed Result
Stand Alone
Receiver
Sensitivity dBm
* Bench Test
Static
Sensitivity dBm
Model Number
(Tower Top Box)
Serial Number
(Tower Top Box)
Table 4: Bench Test Results.
* Default “TTA NET GAIN“ Attenuation (3.0 dB)
* Default “DISTRIBUTION” Attenuation (1.0 dB)
Figure 6: Default display.
Figure 5: MCU software version is displayed briefly
during the boot-up sequence.