Nikrans NS-550GDW, Installation Manual

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Status ALARM
It is working in linearity
Green
Warning: Input signals may be not enough, so please check on coverage effect, do not do anything if it is
good coverage; otherwise please adjust the repeater system to get better coverage.
A little bit stronger input signals or slight self oscillation have occurred.
Orange
Solution: Please adjust antennas or use MGC to reduce the repeater gain, till you find “edge point” with
green LED (I.E. the Alarm LED must stay at green color, and at the edge of turning Orange), and let the
repeater work at this point. MGC is the last measure to take as it will shorten the coverage.
Red for
5
seconds
and then
off
There are strong input signals or severe self oscillations (loop), please enlarge the distance or make use
of barriers between antennas, or adjust the antennas’ angles, and last step is to adjust the repeater by
DIP switch.
Remark : Please note that Alarm LED works on repeater downlink signals only. I.E. the repeater input signals from CELL
TOWER.
Single system repeater only has one set of power and alarm LEDS, while dual system have two sets of power and alarm
LEDS, and three system repeaters have three sets of LEDS. Each system has own relevant LED and please refer to the
correct LED for system performance evaluation.
Then repeater with plastic closet is designed with LEDS of “Alarm LOW” and “Alarm HIGH”. When it is used for single
system of CDMA800, GSM850 and GSM900, only “Alarm Low” LED works, and “Alarm HIGH” LED is no use; when it is used
for single system of DCS, PCS, CDMA1900, WCDMA or AWS, “Alarm HIGH” LED works, and “Alarm LOW” LED is no use.
When the repeater supports two systems, “Alarm Low” and “Alarm HIGH” both work and support relevant low and high
frequencies.
Manual Gain Control (MGC)
DIP Switch can be used to adjust the repeater gain when Alarm LED is orange or even RED. The principle is that
repeater alarm LED must be green color.
For single system metal closet:
Switches 1.2 represent Downlink and 3.4 represent Uplink. When it is necessary to adjust the gain by DIP switch, firstly
please adjust Downlink gain according to input signals, secondly please adjust Uplink gain according to Downlink gain.
The DIP Switches have default ‘OFF’ status; please push relevant switches to “ON” position if certain attenuation value
needs to be achieved.
DIP switch downlink attenuation setting: