MAIN/STANDBY 125 WATT RADIOBEACON TRANSMITTERS WITH CRCU and NDDS/T
(USER SUPPLIED ENCLOSURE/CABINET)
IS02007 (Page 4)
15 February 2002
(c) The
B+VDC
output at TB1-10 of the
transmitter will be the B+ voltage.
(d) The
remote shutdown alarm
output at TB2-7 of
the transmitter will be an open collector.
(e) The
+15VDC
output, for the ATU, at TB2-8 of
the transmitter will be 0.0VDC.
(f) The ATU controls at TB2-3/4/5 of the
transmitter will have no influence.
4.1.1.2
When a transmitter is to be enabled, as the
main
or
standby
transmitter, its
stby on/off
input will
be 0.0VDC. The transmitter will be turned on and
the following will be true:
(a) The
+24VDC
output at A7TB6-6 of the
transmitter will be +24VDC.
(b) The
+15VDC
output at TB2-1 of the
transmitter will be +15VDC.
(c) The
B+VDC
output at TB1-10 of the
transmitter will still be the B+VDC.
(d) The
remote shutdown alarm
output at TB2-7 of
the transmitter will be a current-sink-to-ground.
(e) The
+15VDC
output, for the ATU, at TB2-8 of
the transmitter will be +15VDC.
(f)
The ATU controls at TB2-3, TB2-4 and TB2-5
of the transmitter will be the remote tuning
control source for the ATU.
4.1.1.3
If an operational transmitter shuts down,
its main/standby related outputs will immediately
assume the states identified in steps (a) through (f) of
paragraph 4.1.1.1.
4.2
SYSTEM ON/OFF STATUS:
The
status of the
shutdown alarm
output at 3TB1-3 or the
transmitter on/off status
output at 3TB2-10 is
determined by the status of relay 3K1.
4.2.1
If any transmitter is operational,
regardless of the main/standby status, +24VDC will
be applied to 3TB1-1 or 3TB1-2. Relay 3K1 will be
held energized.
(a) The
xmtr on
output at 3TB2-10 will be a
ground potential.
(b) The
sht dn alm
output at 3TB1-3 will be a
positive DC voltage.
4.2.2
If both in-circuit transmitters are shut
down and the system is non-operational, regardless
of the reason, +24VDC will not be applied to 3TB1-
1/3TB1-2. Relay 3K1 will be de-energized.
(a) The
xmtr on
output at 3TB2-10 will be a
positive DC voltage.
(b) The
sht dn alm
output at 3TB1-3 will be a
ground potential.
4.3 B+VDC
STATUS:
If a transmitter is
operational, regardless of the main/standby status; its
B+VDC will be applied thru 3TB2-11 or 3TB2-5,
whichever is applicable, to 3TB2-12.
4.4 MAIN/STANDBY
CONFIGURATION:
When the '
A
' and '
B
'
transmitters are both in-circuit and they are
operationally available, they will be operating as a
main/standby transmitter system. One of the
transmitters will be inhibited by the application of a
+15VDC
stby on/off
input to its TB1-6 and it will be
held in reserve as the
standby
transmitter.
4.4.1
Main Transmitter Selection:
The
setting of the
SELECT MAIN TX
switch (3S1)
determines which transmitter, '
A
' or '
B
', is selected as
the
main
transmitter. The
SELECT MAIN TX
switch
performs three functions:
(a) It ensures the transmitter not selected as the
main
transmitter is held in reserve as the
standby
transmitter, as long as the selected
main
transmitter is operational. It does this by
routing the +15VDC applied to 3TB2-7 or
3TB2-8, from the
main
transmitter, through
3TB2-1 or 3TB2-2 to TB1-6 of the
standby
transmitter as its
stby on/off
input.
(b) It ensures the state of
main tx status
relay K5
is controlled by the shutdown alarm (
sht dn
alm
) output of the selected
main
transmitter.
Relay K5 will be energized when the selected
main
transmitter is operational and applying a
ground as the
changeover alarm
. It will be de-
