Harris ATLAS ANALOGUE, Руководство пользователя

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7/26/05 888-2523-001 4-1
WARNING: Disconnect primary power prior to servicing.
ATLAS Analogue
Section 4
Theory of
Operation
4.1 Introduction
This section contains detailed descriptions of the Atlas Series transmitter and its
internal sub-assemblies and any pertinent information regarding the external assemblies
such as the pump module and heat exchanger.
The rest of this section will be broken up into 4 main topics:
•
Control System
•
RF System
•
Power Supplies
•
Cooling System
4.1.1 Active Logic Symbols
Each logic signal has an active and inactive state and a unique name within the system.
To differentiate between active high or active low logic states on the schematics, a
forward slash (/) is placed in front of an active LOW signal name such as /RF_MUTE.
This means that if this logic line is pulled low, the transmitter RF will be muted. By the
same logic, the signal RF_MUTE_LED (an active high signal with no forward slash)
will turn on the RF mute LED when it goes high.
In some cases, a logic signal may act as a toggle with both states active, as with the
signal /ON_OFF, where LOW = ON and a HIGH = OFF. If this signal is inverted it
would be ON_/OFF.