Axcera DT325B, Инструкция по эксплуатации

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350-Watt Digital VHF LB Transmitter Chapter 3, Installation and Setup Procedure
DT325B, Rev. 0 3-7
3.4 Setup and Operation Procedures
The transmitter should initially be turned
on with the RF output of the coaxial
switch terminated into a dummy load of
at least 350W. If a load is not available,
check that the output is connected to the
antenna.
Check that the circuit breaker mounted
on the rear panel near the AC input jack
of driver/amplifier chassis assembly is
On. Check that the circuit breaker,
located on the front of the VHF amplifier
tray, is On.
On the driver/amplifier, switch the
Operate/Standby switch to Operate. The
VHF amplifier tray should go to operate.
Observe the power supply reading on the
front panel of the VHF amplifier tray. It
should be +28 VDC.
NOTE: If the transmitter does not switch
to Operate when the selected On Air
exciter is placed in Operate, check that
the protection interlock is present,
normally by jumpering TB30-5 to TB30-
15. The interlock or the jumper provides
the remote interlock needed by the
transmitter to allow it to switch to
Operate.
On the LCD screen in the driver/amplifier
chassis assembly, look at the % Output
Power indication, it should read near to
the level as stated on the final test data
sheet for your transmitter. If necessary,
adjust the output power of the
transmitter using the Driver/
Amplifier LCD display while viewing the
Power Control Screen in the Set Up Menu
and increase or decrease the level as
needed to attain 100% output power of
the transmitter. As the output power
level is being checked, observe the LCD
screen reading in the % Reflected Power
position. If the % Reflected Power is
very high, above 10%, a problem may
exist with the output coaxial lines and
they will need to be checked. A center
bullet missing from the coax lines or
loose bolts is a probable cause. Repair
as needed to attain a <5% reflected
reading.
The gain and phase control on the front
panel of the VHF amplifier tray was
adjusted at the factory to obtain an
output of 100% for the transmitter and
should not need to be readjusted. Refer
to the Test Data Sheet for the transmitter
to compare the final readings from the
factory with the readings on the tray after
the setup. They should be very similar.
If a reading is off by a significant amount,
refer to the power adjustment procedure
for the VHF amplifier tray in Chapter 5,
Detailed Alignment Procedures, of this
manual before trying to make any
adjustments.
If a dummy load is connected to the
transmitter, switch the main on/off circuit
breaker, for the system, Off. Remove the
dummy load and make all of the
connections needed to connect the
transmitter to the antenna. Switch the
main on/off circuit breaker On and the
Operate/Standby switch to operate. If
needed, adjust the output power, using
the Axciter LCD screen in the Upconverter
menu screen, to attain 100% output of
the transmitter.
If the transmitter is already connected to
the antenna, check that the output is
100%. If necessary, adjust the output
power, using the Axciter LCD screen in
the Upconverter menu screen, to attain
100% output of the transmitter.
3.4.1 Driver/Amplifier Chassis
Modules front panel LEDs
The following LED descriptions are
typical of the operating On Air Exciter.