NORMARC NM 7000 Series, Инструкция по установке и пусконаладке

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1.2.8 Ident Tone Modulation Depth
Connect the Field Test Set to the CSB BNC test connector in the Cabinet’s Change-over sec-
tion.
(Insert a 20 dB attenuator at the input of the Field Test Set in order to avoid overloading).
Set the Ident Control to CONTINUOUS from the RMM Program or the Local Display/Key-
board.
On the Field Test Set, press IDENT.
1020 Hz modulation depth can be adjusted from the RMM Program or the Local Display/Key-
board.
Adjust modulation depth to 10.0% +/-0.3%.
An alternative method of checking 1020 Hz modulation depth to 10% is described below:
Connect the oscilloscope to the BNC test Connector labelled CSB.
Switch off the 90 Hz modulation and the 1020 Hz modulation.
Note the peak-to-peak deflection of the remaining 150 Hz waveform.
Then switch off the 150 Hz modulation and switch the 1020 Hz modulation to CONTINUOUS.
For mod. Depth 10%.The observed 1020 Hz peak-to-peak waveform amplitude should be
50% of the 150 Hz amplitude.
1.2.9 RF Frequency Adjustment
Fine-adjustment of the operating frequency can be carried out by adjusting C1 in the
OS1221A/B RF Oscillator module.
The top cover must be removed.
Set the OS1221A/B on an extention board.
In order to monitor the frequency, connect the Frequency Counter to the BNC test connector
labelled CSB. (Make sure the transmitter under test is routed to Antenna).
If necessary for reliable counting switch off modulation tones.
Adjust until frequency is less than 1 kHz from operating frequency. Trimmer C1 adjusts course
and clearance frequencies simultaneously.
1.3 Antenna System Adjustments
After the transmitters has been alligned correctly the antenna system must be alligned. This
includes mechanical adjustments of the Antenna System, electrical adjustments (phasing)
and adjustments of the ADU and MCU.