MAIN/STANDBY 125 WATT RADIOBEACON WITH NDDS/T
(INSTALLED
IN NARB07 CABINET)
IS02001 (Page 2)
29 January 2002
(f) If transmitter 'A' is selected as the 'main'
transmitter, an open collector
SHTDN ALM
(
B
)
signal will be applied to TB3-5 from TB2-7
('shutdown') of transmitter 'B', indicating it is
not turned on.
(g) If transmitter 'B' is selected as the 'main'
transmitter, an open collector
SHTDN ALM
(
A
)
signal will be applied to TB3-4 from TB2-7
('shutdown') of transmitter 'A', indicating it is
not turned on.
4.2
STANDBY TX OPERATION:
If the
main
transmitter shuts down because an abnormal
condition was sensed for more than 20 seconds, or for
any other reason, the following will occur:
(a) 15VDC that was being applied to TB1-6 of the
standby
transmitter, from TB2-1 of
main
transmitter, will be switched off. The
standby
transmitter's DC power supplies will turn on and
provide B+VDC, 24VDC and 15VDC outputs.
It will also produce an RF output.
(b) The source for the NDDS/T's 24VDC inputs
will be the
standby
transmitter. The NDDS/T
will provide a RF signal at the transmitter's
operating frequency to J3 (Ext RF Drive) of the
standby
transmitter.
(c) If
transmitter
A
was the
main
transmitter, the
main/standby relay in its harmonic filter will de-
energize. If transmitter
B
was the
main
transmitter, the main/standby relay in
transmitter
A
's harmonic filter will energize.
The
standby
transmitter's RF output will be
routed to the cabinet's
RF OUT
coaxial connector
(J1).
(d) The source for the antenna tuning unit controls,
at TB3-6 thru TB3-10 (
ATU CONT
) of the
cabinet's customer interface assembly, will be
the
standby
transmitter.
(e) The standby transmitter will be providing the
'audio out' (
RMT AUD
) sample.
(f) If transmitter 'A' is selected as the 'main'
transmitter, an open collector
SHTDN ALM
(
A
)
signal will be applied to TB3-4 from TB2-7
('shutdown') of transmitter 'A', indicating it is
not turned on.
(g) If transmitter 'B' is selected as the 'main'
transmitter, an open collector
SHTDN ALM
(
B
)
signal will be applied to TB3-5 from TB2-7
('shutdown') of transmitter 'B', indicating it is
not turned on.
INSTALLATION INFORMATION
5.
Complete or verify the following
requirements are completed during installation of the
transmitter/cabinet.
(a) Ensure the cabinet will not topple, when the
transmitters are installed and one or both are
extended on their drawer slides, by securely
bolting the cabinet to its mounting surface or by
rigidly securing it using some other suitable
means. There are four bolt holes in the base of
the cabinet to accommodate securing hardware.
(b) Connect appropriate AC power source wiring
(115VAC, 60Hz or 230VAC, 50/60Hz) to
duplex receptacle J2, ensuring wiring passes
through and is secured by a cable clamp in the
cabinet's cable entry hole.
(c)
Connect external control/monitor wiring to TB2
and TB3 of the customer interface assembly as
depicted in figure 2 of these instructions.
Ensure wires pass through and are secured by a
cable clamp in the cabinet's cable entry hole.
Refer to figure 4 for the interface assembly
detail.
NOTE
If an external power trim control circuit is to be used,
remove or verify both power trim bypass links
(between TB2-4/TB2-5 and between TB2-7/TB2-8)
are removed.
If an external power trim control circuit is not used,
install or verify both power trim bypass links (between
TB2-4/TB2-5 and between TB2-7/TB2-8) are
installed.
(d) Connect a continuous, insulated, 4AWG copper
wire or one-inch copper braid between the
station lightning/safety ground and the cabinet's
safety ground connection, noting it is located on
the top of the cabinet adjacent to the RF output
connector (J1). Ensure this wire does not
