Nautel NV30LT-N, Руководство по эксплуатации и техническому обслуживанию

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NV30LT-N OPERATIONS & MAINTENANCE MANUAL DESCRIPTION
VERSION 0.1 2015-03-01 PAGE 3.1.3
Control/Monitor Stage
See electrical schematic Figure SD-4 and SD-5. The control/monitor stage performs many critical
functions for the transmitter. It:
 contains monitoring and protection circuits to prevent transmitter damage under adverse or
fault conditions, including high speed SWR protection, high reject power protection and
interlock/muting.
 monitors the current value of various parameters including cooling fan tachometer outputs,
transmitter output forward and reflected power, module temperature, PA current levels, and
PA power supply status signals.
 measures and monitors the output voltage from the power supply modules as well as the low
voltage power supplies.
 generates the signals that enable the power supply modules and control their output voltage.
 provides the status of any controller fault conditions.
 contains an integral DSP that performs all audio processing including filtering and FM
baseband modulation.
 interfaces with the RF and power supply sections of the transmitter to perform control and
monitoring functions.
 provides local and remote interfacing for the transmitter. Local interfacing is performed via
the front panel display (U1) - a 4 x 20 graphic LCD display - and its adjacent keypad. The UI
contains a menu-based series of pages that serve specific functions. Similar interfacing, as
well as more advanced functionality, is available on a remotely accessed AUI. The AUI is a
flash graphic that can be used on any web-based PC or handheld device.
The primary components of the control/monitor stage are the exciter/controller PWB (A4A1), which is
part of the controller (A4) and the module control/interface PWB (A3, A18 and A34).
The UI interface PWB (A2) provides an interface between the front panel display (U1) and the rack 1
module control/interface PWB (). It also contains the pushbutton switches (
RF ON , RF OFF and LOCAL/
REMOTE ) and associated status LEDs that protrude through the front panel, below the UI.
An optional remote interface PWB (A16) provides a more convenient method to remotely control and
monitor the transmitter, including a more accessible LAN port. It contains push-button switches that
provide backup control for the RF on/off, local/remote, power increase/decrease, preset selection,
enabling/disabling auto exciter changeover, active exciter selection and reset functions. It also contains
LEDs that serve as an alternate means to monitor status (local/remote and RF on/off) and various status
and alarm parameters.