3
6
5
3.3c
TTU500FA Troubleshooting Chart
:
The following chart is meant as an aid for uncovering faults that have developed in this transmitter.
During normal operation, all indicator LEDs are green, except the AMPLIFIER and VSWR OVLD
LEDs which are yellow and red, respectively, but are normally extinguished (in conjunction with the
SWEEP MODE light). This chart lists the LEDs that are indicating a fault by not appearing in their
normal state. If a problem develops with the transmitter, note the state of each indicator and
compare this to the chart below.
TTU500FA TROUBLESHOOTING CHART
PROBLEM
INDICATORS
CAUSE
SOLUTION
NO OUTPUT
POWER
ALL EXCITER DRAWER
INDICATORS UNLIT
Exciter Power Supply
faulty
Check 28V/15V/5V Power
Supply. Replace if
necessary.
SYNTH LOCK
UNLIT
POWER SUPPLY
UNLIT
RF POWER METER
0%
Defective Synthesizer
Check synthesizer for
correct output level and
frequency. Replace if
necessary.
OPERATE
UNLIT
POWER SUPPLY
UNLIT
RF POWER METER
0%
Operate/Standby
switch in Standby
Place switch (in) to
Operate.
Ground on A8J1-5 of
Remote plug
Ensure transmitter has
not been placed in
standby through remote
system.
No video at input of
modulator
Check video program
input and VDS tally.
VSWR RESET
RED
RF POWER METER
0%
VSWR overload
Clear VSWR problem
and press Reset button.
IF STATUS
UNLIT
RF POWER METER
0%
No IF input from
modulator
Fix cables or replace
modulator.
AMPLIFIER STATUS
UNLIT
RF POWER METER
0%
2 Watt Amplifier faulty
Replace module.
LOW OUTPUT
POWER
AMPLIFIER TEMP
YELLOW
POWER SUPPLY
UNLIT
RF POWER
<100%
High 300W Amplifier
temperature
Insure site ambient
temperature is controlled.
Check fans for proper
operation and adequate
space to ventilate drawer.