9-6
September 27, 2000
68P81093C75-O
Interpreting LED
Indicators
Several LED indicators are provided on the front panels and on the
top panel of the chassis. These LEDs give a quick status indication
of the station equipment. The Station Control Module LEDs are
visible from the station’s top panel. Observing the other LEDs
requires the removal of the station’s chassis from the case. See
Figure 5 for the location of all LED indicators on the station’s
equipment. A listing of each LED indicator, along with a description
of the status indicated by each LED, is shown in Table 9.
Table 9: PDR 3500 Station LED Indicator Functions
LED Location
LED Name
Status Definition
EXCITER MODULE
Tx Lock
– GREEN when Exciter synthesizer is locked; module fully functional.
– OFF when:
synthesizer is out of lock
or
+5V, +14.2V, or both are absent
PA Full
– GREEN when transmitter is keyed and PA output power is at expected
power level (as set by technician via RSS during station alignment)
– OFF when:
PA not keyed
or
PA keyed, but PA output power is not at expected power level
(as set by technician via RSS during station alignment)
PA Low
– YELLOW when transmitter is keyed and PA output power is less than
expected power level (as set by technician via RSS during station alignment) but
not shut down (for example, during power cutback mode)
– OFF when:
PA not keyed
or
PA keyed, and PA output power is at expected power level
(as set by technician via RSS during station alignment)
PA Fail
– RED when:
No PA output power (for example, during PA shutdown mode);
LED status is latched, thereby indicating status during current key or
for previous key
NOTE: Any component associated with the PA could cause LED to light.
These include the Exciter, PA, and transmitter circuitry on the backplane.
– FLASHING when PA is in the Test Mode (activated by technician via
RSS; when in Test Mode, power cutback, and open
power loop protection are disabled)
– OFF when PA output power is either at expected level, or at specific
cutback levels (any level other than shutdown); LED status is latched,
thereby indicating status during current key, or for previous key.
TOP PANEL
Pwr/Tx
– GREEN when AC or DC input power is present
– RED when station is transmitting
– OFF when AC or DC input power is absent
