UHF Analog Driver/Transmitter/
Chapter 4, Circuit Descriptions
Translator
LX Series, Rev. 3
4-29
output of U28B at pin 7 is connected
through the reflected calibration pot
R163 to U28C. The output is split with
one part connected to J9 pin 5, the
Reflected Power Output level of the
board. The other part of the split from
U28C connects to the comparator IC
U28D that has a reference level
connected to the other input. If the
reflected level increases above the
reference level a low output is produced
and connected to the Reflected Power
Shutdown circuit at CR28. The low shuts
off Q14 causing pin 3 to go high that is
connected to the inverter U15C. The
output of U15C goes low producing a
Reflected Power Fault that is connected
to an output of the board, the Fault Alert
circuit and also shuts down Amplifier #1.
Gain of the power measurements is
completed through software. Only the
Aural Null and Offset Null need to be
done through front panel pots.
This completes the description of the
Driver Amplifier Module Assembly, which
is used in high power transmitters with
external PA assemblies.
The RF output of the driver amplifier
module assembly connects to the output of
the Exciter/Amplifier chassis assembly at
the “N” type connector Jack J25. In a High
Power System, the RF output at J25
connects to J200 the RF input to the
external Power Amplifier Assembly.
NOTE:
In systems with two exciters and
an exciter switcher, the outputs of the two
exciters connect to the exciter switcher
tray and the RF output from the selected
exciter connects to J200 the RF input to
the external Power Amplifier Assembly, or
a splitter assembly, or directly to the
bandpass filter for the system.
This also completes the description for the
entire Exciter/Amplifier chassis assembly.
Содержание INNOVATOR
Страница 99: ...APPENDIX A LX SERIES ANALOG SYSTEM SPECIFICATIONS...
Страница 102: ...APPENDIX B DRAWINGS AND PARTS LISTS...
Страница 105: ...APPENDIX C TRANSMITTER LOG SHEET...