C-COR Flex Max901e, Руководство по эксплуатации оборудования

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6
1502154 Rev D Troubleshooting 6-3
Quick Forward Outage Check
This check is not a comprehensive check of all amplifier functions. The steps listed here can help
you quickly determine whether or not an amplifier is causing a signal outage to subscribers
downstream in the forward path, especially when no automated status monitoring is used.
➤
To perform a quick forward outage check
1. Use a signal level meter to measure an active frequency/channel at the testpoint of an active
forward output port (Port 3 or 4 recommended). Choose a frequency/channel that has
historical (or designed) values to compare against.
2. If the output signal is at a reasonable level, check devices further down the signal path; if
not, check the input signal level at the
PORT 1 FWD I/P TP
.
3. If the input signal is at a reasonable level, but the output signal is not, use the
troubleshooting sections in this book to see if this amplifier is the source of the outage. If
the input signal is not at a reasonable level, check amplifiers closer to the signal source or
headend.
Reasonable levels are determined by the system design. Your system map and Amplifier Data Sheets
can give you the designed and historical levels. When trying to fix an outage quickly, you may accept
a much wider range of values than when balancing or sweeping a system. You can usually fix smaller
problems after service is restored.
When you have many amplifiers to check, a good general method for finding the source of an outage
is the 50/50 method. The 50/50 method consists of testing for RF signals and power problems at a
device halfway through the cascade (or problem leg). Keep dividing the problem section in half until
you isolate the malfunction. You can combine this method with other methods.
An Flex Max901e that outputs reasonable RF signal levels may not pass power to the next device
(likely due to a blown fuse). The lack of power passing is then caught when the next active device
in the signal path is checked, which leads you back to the problem amplifier.
Power Supply Troubleshooting
Refer to Voltage Testing on page 5-5 to troubleshoot the power supply.