Nautel VX150, Operation & Maintenance Manual

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VX150 TO VX2 OPERATIONS & MAINTENANCE MANUAL DESCRIPTION
VERSION 1.0 2022-12-08 PAGE 2.1.3
Exciter PWB
The Exciter PWB (A1) accepts external audio program information and generates the modulated RF
drive source for the IPA PWB (A6). It performs all primary control functions of the transmitter.
Other functions of the Exciter PWB are:
 accepts analog modulation sources from Analog Audio PWB
 accepts digital modulation sources
 generates the signals that enables the PA Power Supply and controls its output voltage
 hosts Ethernet server and remote control I/O
 accepts forward power sample from directional coupler
 accepts interlock input and provides interlock/muting protection
 accepts SWR shutdown from System Interface PWB
Analog Audio PWB
The Analog Audio PWB (A2) accepts external audio and composite signals, digitizing them for further
processing on the Exciter PWB (see the
VX150 to VX2 Installation Manual
for details on various
program input types). It also generates a Pilot Sample.
System Interface PWB
The System Interface PWB (A3) interfaces with the Exciter PWB to perform the following functions:
 contains monitoring and protection circuits to prevent transmitter damage under adverse or
fault conditions, including high speed SWR protection.
 monitors the current value of various parameters including cooling fan tachometer outputs,
transmitter output reflected power, heatsink and intake temperature, and PA current levels.
 measures and monitors the output voltage from the +53 V PA Power Supply as well as the
low voltage power supplies.
 provides local interfacing for the transmitter. Local interfacing is performed via the local FPUI
on the transmitter and the front panel LCD display (320 x 240 pixels). The FPUI contains a
menu-based series of pages that serve specific functions.