LX Series Digital
Chapter 2, Amplifier Assembly Description,
Power Amplifier Assembly
Maintenance & Remote Control Connections
Volume 2, Rev. 1
2-5
of the cabinet. A 500 Watt reject load
(A18), mounted on the roof of the
cabinet, connects to J4 on the hybrid
combiner to dissipate reject power.
Another 500 Watt reject load (A9), also
mounted on the roof, connects to J5 on
the hybrid combiner to dissipate reject
power. Thermal switches (A9-A1 & A18-
A1) are mounted to the reject loads and
supply overtemperature faults, at 175º F.,
to the driver assembly at TB30-7 & 15, if
a problem occurs in the output lines.
NOTE:
If an overtemperature fault occurs,
it must be manually reset on the system
controller after repairs are made. The
combined output of the hybrid combiner is
cabled to the externally mounted
assemblies, which consist of (A15) the
digital bandpass filter, (A14) the low pass
filter, (A10) the optional output trap filter
and (A11) the output coupler. The output
coupler assembly supplies a forward and a
reflected sample to the (A44) Dual Peak
Detector Board. The Dual Peak Detector
Board supplies samples to the
exciter/driver for metering purposes. The
reflected sample connects to TB31-13 and
the forward sample to TB31-14. The RF
output for the transmitter is at J2 the 3-
1/8” EIA connector on the (A11) output
coupler assembly.
2.1.2.4 2kW Digital Output System
Configuration
In a 2 kW digital system, the outputs of
the four power amplifier chassis
assemblies must be combined. This is
accomplished by combining two power
amplifier chassis assemblies, creating two
outputs then combing these into one
output. In the (A1) cabinet assembly, the
outputs of the (A1-A3 and A1-A6) power
amplifiers at the “7/16” connectors J205,
are cabled to the (A1-A7) hybrid
combiner, mounted to the input jack of
the (A1-A8) bandpass filter. A 1 kW
reject load (A1-A9), that dissipates reject
power, is mounted on a shelf inside the
(A1) cabinet and is connected to (J4) on
the hybrid combiner. A thermal switch
(A1-A9-A1) is mounted to the reject load
and supplies an overtemperature fault, at
175º F., to the driver assembly at TB30-7
& 15, if a problem occurs in the output
lines for the (A1) amplifier cabinet. The
combined output at (A1-A7-J3) of the
hybrid combiner connects to the (A1-A8)
bandpass filter for filtering before it is
connected either directly to the “7/8”
Jack J1 on (A3) the 2 way combiner
assembly mounted on the roof of the
cabinets, or through the optional (A1-
A12) trap filter and then to the 2 way
combiner.
In the (A2) cabinet, the outputs of the
(A2-A3 and A2-A6) power amplifiers at
the “7/16” connectors J205, are cabled to
(A2-A7) hybrid combiner. A 1 kW reject
load (A2-A9) connects to (J4) on the
hybrid combiner to dissipate reject
power. A thermal switch (A2-A9-A1) is
mounted to the reject load and supplies
an overtemperature fault, at 175º F., to
the driver assembly at TB30-7 & 15, if a
problem occurs in the output lines for the
(A2) amplifier cabinet. The combined
output at (A2-A7-J3) of the hybrid
combiner connects to the (A2-A8)
bandpass filter for filtering before it is
connected either directly to the “7/8”
Jack J2 on (A3) the 2 way combiner
assembly mounted on the roof of the
cabinets, or through the optional (A2-
A12) trap filter and then to the 2 way
combiner. The combined output of the
(A3) 2 way combiner at the 1-5/8”
connector (A3-J3) is connected to the
input of the (A4) output coupler. The
output coupler assembly supplies a
forward power sample at (A4-J3) and a
reflected sample at (A4-J6) to the (A44)
Dual Peak Detector Board. The Dual
Peak Detector Board supplies a reflected
power sample to TB31-13 and a forward
power sample to TB31-14 on the
exciter/driver for metering purposes.
The RF output for the transmitter is at J2
the 1-5/8” connector on the (A4) output
coupler assembly.
2.1.2.5 2.5kW Digital Output System
Configuration
In a 2.5 kW digital system, the outputs of
the five power amplifier chassis
assemblies must be combined. This is
