Bird Technologies 429-83H-01 Series-Manual - Manual (Page 32)

TX RX Systems Inc. Manual 7-9439-6 09/03/09 Page 24
scroll down from the default display to the SOFT-
WARE VERSION sub-menu.
Front Panel LEDs
Status indicator LED’s for all three amplifiers illumi-
nate in one of two colors. The meaning of each
color is summarized in table 7. During normal oper-
ation, the LED’s for amplifier A and the BASE
amplifier will glow green, indicating normal current
draw. The LED for amplifier B will be off indicating
this amplifier is in stand-by.
Form-C Contacts
ALARM form-C relay contacts are located at the
back of the MCU (see figure 14). These screw ter-
minals are intended for connection to the cus-
tomer’s supervisory and data acquisition system.
Both normally open and normally closed contacts
are available. There are two sets of screw termi-
nals for customer convenience. Both sets of screw
terminals have the same functionality.
ALARMS
The system will alarm when either of two distinct
conditions occur including an abnormal current
flow in any of the systems three amplifier assem-
blies or a loss of serial communications between
the base unit and the tower top box.
When the current to any of the three amplifiers
deviates from normal by approximately +/- 55 ma
or greater the specific device LED will glow a solid
red. In addition, amplifier switching will take place
in the tower top box if the fault lies with one of the
tower top amplifiers. There is no switching provi-
sion for the amplifier in the MCU. The ALARM
Form-C contacts located at the back of the unit will
also change state.
Fault detection circuitry continuously monitors the
DC power operation of the primary tower top quad-
amplifier and automatically switches to the identical
secondary quad-amplifier if conditions indicate a
primary malfunction. If the secondary quad-ampli-
fier malfunctions, operation switches to whichever
amplifier is still providing some gain due to opera-
tion of one of its amplification paths.
A loss of communications (along the main trans-
mission line) between the microprocessors in the
base unit and tower box will cause the front panel
A and B indicator LED’s to flash RED. The ALARM
Form-C contacts located at the back of the unit will
also change state.
THE TEST MODE
The TEST sub-menu allows the field engineer to
choose the active tower top amplifier as well as
control the input of each of the tower top amplifiers
via software. The base amplifier is always active.
When you use functions in the TEST sub-menu
you are operating the system in the test mode. Be
aware that some of these tests will interrupt the RF
signal path through the tower top box and on-air
signals will not be passed to the station receivers.
We recommend that when you are in the test mode
and you complete your testing use the CANCEL
button to exit back to normal mode and the default
display. If you exit the test mode without using the
CANCEL button and leave one of the amplifiers in
other than its normal operating condition the mes-
sage “NonFunctional” will appear in the LNA X
ACTIVE sub-menu. As a safety feature the system
will switch out of the test mode and back into the
normal mode of operation after about 9 minutes of
inactivity. Each of the three functions available
through the TEST sub-menu is described below.
Set LNA X Active
Allows the selection of the active amplifier via soft-
ware interface.
1) From the TEST sub-menu display use the
ARROW buttons to scroll over to the SET LNA
“A (or) B” ACTIVE menu choice, depending on
which amplifier you want to choose as the
active amp, and press the ENTER button.
2) If you choose to make the already active ampli-
fier active again, the system will return you to
the TEST sub-menu. If you choose to make the
non-active amplifier active, then the “Test TTA
Offline” message will appear. The RF signal
path through the tower top box will be inter-
rupted and on-air signals will not be passed to
the station receivers.
3) Pressing the CANCEL button returns you to the
default display. Whichever amplifier you had
selected to be active in the TEST sub-menu will
now be the active amplifier back in the normal
mode and on-air signals will again pass through
to the station receivers.