User's Manual Part 2

6-7
Problem/Symptoms Check
No downlink signal output when
all diagnostic LEDs are green.
Make sure that there is a reasonable amount of power at the
input of the Main Hub. Measure the output power of the
coaxial cable using a power meter.
The LGCell is intended for a different frequency band.
Verify that your system corresponds to the desired
frequency spectrum (for example, 800 MHz, 1800 MHz, or
1900 MHz). Check the part number of each unit.
The LGCell is factory set for different bands of operation.
Please be sure you have the proper band.
The system gain is lower than
specification.
The optical fiber connector is dirty. Clean the fiber ST-
connector, using the manufacturer’s recommended cleaning
procedure.
There are two types of Multi-Mode Fiber (MMF), 62.5/
125
µ
m and 50/125
µ
m. Make sure the vertical run MMF is
the 62.5/125
µ
m type of fiber.
Remote Antenna Unit (RAU)
power LED (green LED) stays
off after you plug in the twisted
pair cable.
The Expansion Hub provides power to the RAU. Make sure
the Expansion Hub is on.
Make sure that the twisted-pair (TP) cable wiring conforms
to the TIA/EIA 568-A standard. (For information about the
standard, refer to
Appendix B – TIA/EIA 568-A
Cabling Standard
.) Use a standard local area network
(LAN) cable tester to perform this test. Possible errors are
wrong wiring and/or cable length.
The LGCell performance is
intermittent when you use it for
the CDMA application.
The uplink and downlink gain is not balanced. A CDMA
system performs active power control between the base
station and the mobile unit. It is important to maintain a
balanced link from the base station ports to the RAU ports
(equal uplink and downlink gain) to optimize the
performance of the LGCell.