Nautel NX50, Руководство по установке

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NX50 Installation Manual Commissioning tasks
Issue 6.1 2021-07-13 Page 9-7
Going on-air
Important:
Before going on the air, if you want the safety interlocks to operate properly, the
shorting jumpers installed in “Pre-commissioning tasks” on page 9-1 , Step 5 should be removed
and the antenna system's interlock should be installed. If you are not using an external system
interlock circuit, leave jumpers installed between TB1-1 and TB1-2 and between TB1-3 and
TB1-4.
When the commissioning tests are successfully completed, connect the studio audio to the
transmitter's audio input connector, follow the steps below to go on-air, and then complete
any emission tests that are required.
1. Turn off the power using the ac disconnect switch, if one is being used, or else at the ac
source.
2. Connect the transmitter's RF output to an antenna system (or verify that the current
connection is intact). Ensure that a ferrite toroid (Nautel Part # LP32) is installed on
the RF coaxial hardline at the transmitter’s output.
3. Turn on the transmitter’s ac power.
4. Connect the desired modulation source to the transmitter (see Section 7, “Planning
audio inputs” on page 7-1 of the Pre-Installation Manual for connection options).
NOTE
:
If analog modulation is being applied, it is recommended that negative modulation peaks
do not exceed -96% and positive peaks do not exceed 140 % to minimize audio distortion caused
by signal clipping .
5. Use the AUI controls to begin transmitter operations. For detailed instructions, refer
to the NX50 Operating and Maintenance Manual.
6. Check the Transmitter Status page of the AUI and verify there are no alarms present.
If any alarms are present, consult the NX50 Troubleshooting Manual for detailed
information on each alarm.
WARNING:
If jumpers are placed between interlock terminals TB1-1/2 and TB1-3/4
on the control/interface pwb, safety features controlled by the
external interlocks will be disabled. A fail safe method of alerting
personnel to this fact should be implemented. Voltages which are
dangerous to life will be present on the RF output stages and the
antenna system if the transmitter is turned on.