User's Guide

1414
Problem: Solution:
Green power LEDs on faceplate not
lit.
Check power source and the AC fuse located in the EIC plug.
Check the DC fuse located inside the 48900 on the side of the
individual amplifier modules. Check connections to the
internal power supply.
Red LED on faceplate is lit.
First try to cycle the power then watch the AGC LEDS to make
sure the unit is not in AGC shut down. If the Fault LED is
cycling then an overdrive condition exists. See AGC
Automatic Shutdown section.
Green power LED lit and no red Fault
LED on faceplate; unit does not
appear to be working.
Check for a break in the donor or distribution networks. Also,
check to ensure the donor signal is still available to the
repeater. An obstruction could be blocking the donor base site
or the donor antenna could have become misaligned. Then,
check the integrity of the distribution network. Coaxial cable
has a minimum bending radius, if that is exceeded the inner
conductor may crack or break causing excessive reflections to
the signals.
Yellow AGC LED is lit.
AGC LEDs indicate an overdrive condition in the respective
link. Reduce the respective link gain via the Gain Adjust until
the LED goes out. Generally, the opposing link gain should be
adjusted to approximately the same setting. If the LED does
not go out, then the input signal is too strong. Sweep the input
to the respective link to identify the source of overdrive. If the
signal is not a desired signal then external filtering should be
considered to attenuate. If the signal(s) are all desired then
attenuate the base port with a 10 dB in-line attenuation pad.
Component Location
Only the power supply is field replaceable part number 31500012900
DC Fuse
Amplifier
Module
Power
Supply