Tait T800 SL2 25W, Руководство по обслуживанию

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M8SL2-00-002-812
T855 Circuit Operation B2.1
© Copyright Tait Electronics Limited August 2004. All rights reserved.
2 T855 Circuit Operation
This section provides a basic description of the circuit operation of the T855 receiver.
Note: Unless otherwise specified, the term “PGM800Win” used in this and follow-
ing sections refers to version 4.02 and later of the software.
Refer to Section 6 where the parts lists, grid reference index and diagrams will provide
detailed information on identifying and locating components and test points on the
main PCB. The parts list and diagrams for the VCO PCB are in Part E.
The following topics are covered in this section.
Section Title Page
2.1 Introduction 2.3
2.2 Receiver Front End 2.4
2.3 Mixer 2.5
2.4 IF Circuitry 2.5
2.5 Noise Mute (Squelch) 2.6
2.6 Carrier Mute 2.6
2.7 Audio Processor 2.7
2.8 Power Supply And Regulators 2.8
2.9 Microcontroller 2.9
2.10 Synthesised Local Oscillator 2.10
2.11 VCO 2.11
2.12 Received Signal Strength Indicator (RSSI) 2.12
Figure Title Page
2.1
2.2
2.3
2.4
2.5
2.6
2.7
T855 High Level Block Diagram
T855 Front End, IF and Mute Block Diagram
T855 Audio Processor Block Diagram
T855 Power Supply And Regulators Block Diagram
T855 Microcontroller Block Diagram
T855 Synthesiser Block Diagram
T855 RSSI Block Diagram (T800-04-0000 RSSI PCB)
2.3
2.4
2.7
2.8
2.9
2.10
2.12