User's Manual

Copyright Crescend Technologies 10 Rev O
6. TROUBLESHOOTING
6.1. INTRODUCTION
This section contains a list of potential problems and suggested actions to be taken. If the
suggested corrective action does not eliminate the problem, please contact your Crescend factory
for further instructions.
NOTE: Check your sales order and equipment warranty before attempting to service or
repair the unit. Do not break the seals on equipment under warranty or the warranty will
be null and void. Do not return equipment for warranty or repair service until proper
shipping instructions are received from the factory.
6.2. TROUBLESHOOTING
Refer to Table 6-1 for troubleshooting suggestions. It has been found that in some cases it may
be necessary to power cycle an amplifier (turn DC power off and back on without RF applied) to
clear an alarm.
Table 6-1. Troubleshooting
INDICATOR LED STATUS OUTPUT POWER STATUS POSSIBLE CAUSE SUGGESTED ACTIONS
Unlit No power No voltage at unit 1. Check power supply voltage DC PWR ON
(Green)
On Set power Normal operation 1. No action required
Frequency is out of
range
1. Check frequency
The input power is
below the low end of
the rated input range
1. Check input power
Power supply voltage
is too low
1. Check power supply voltage
at amplifier DC connector
during key-up
On (all other
alarm LEDs
off)
Problem inside
amplifier
1. Send the unit back to factory
LOW
OUTPUT
(Red)
On (together
with HIGH
VSWR alarm
LED)
Less than set power
Output load VSWR is
much above 3.5:1
1. Turn off amplifier (or remove
RF input)
2. Check output connections
and cables for integrity and
tightness
3. Check antenna, combiner,
etc. for proper return loss
HIGH VSWR
(Red)
On Less than set power Output load VSWR is
above 3.5:1
1. Turn off amplifier (or remove
RF input)
2. Check output connections
and cables for integrity and
tightness
3. Check antenna, combiner,
etc. for proper return loss
Fan is not rotating 1. Check if +13 VDC is present
on the FAN feedthrough pin
when rf input present (after
3 sec turn on delay)
2. Check if anything is
physically stopping rotation
3. If fan has failed, replace fan
with same or similar fan
OVER TEMP
(Red)
On Less than set power
Power supply voltage
is too low causing
insufficient air flow
1. Check power supply voltage