Broadcast Electronics AM-2.5E, User Manual

Page: 90 / 320

5-5
WARNING: DISCONNECT POWER PRIOR TO SERVICING
WARNING
WARNING
WARNING
WARNING
THE TRANSMITTER CONTAINS MULTIPLE CIRCUIT
GROUNDS WITH HIGH AC AND DC POTENTIALS
WITH RESPECT TO THE CABINET WHICH IS AT
EARTH POTENTIAL. DO NOT ENERGIZE THE
TRANSMITTER WITH TEST EQUIPMENT CON
NECTED TO THE TRANSMITTER OUTPUT
NETWORK, RF POWER MODULE, RF COMBINER, OR
POWER SUPPLY COMPONENTS.
5-23. The AM-2.5E/AM-5E transmitters are equipped with extensive indicator and meter
circuitry to allow the operator to isolate problems to a specific area within the transmitter.
Due to the hazardous voltages and currents contained in the equipment, operation of the
transmitter with test equipment connected to transmitter output network, RF power
module, RF combiner, or power supply components is extremely dangerous and must not
be attempted. Test equipment may be connected to the ECU circuit boards from the front
of the transmitter using the supplied extender circuit board with power energized.
Therefore, the transmitter indicators and meters must be used to isolate a problem to a
specific area.
5-24.
TRANSMITTER INDICATORS.
The following text presents a description of the transmitter
indicators and typical meter indications. Refer to the following text as required to
determine the function of a specific indicator.
TABLE 5-1. AM-2.5E/AM-5E INDICATORS
(Sheet 1 of 4)
ASSEMBLY INDICATOR FUNCTION
ECU ASSEMBLY
TRANSMITTER MONITOR
EXCITER GREEN DISPLAY - Indicates normal exciter
operation.
RED DISPLAY - Indicates no exciter RF drive or
PWM output.
POWER MODULES GREEN DISPLAY - Indicates all RF power modules
are operating normally.
YELLOW DISPLAY - Indicates one or more RF power
modules are removed from the transmitter for
maintenance.
RED DISPLAY - Indicates a modulator or power
amplifier circuit board fault in one or more RF power
modules.
POWER SUPPLY GREEN DISPLAY - Indicates normal power supply
operation.
RED DISPLAY - Indicates an open loop or over-
voltage fault in one or more power supply modules.
YELLOW Display - Indicates one or more power
supplies are removed from the transmitter.