EFJohnson 001-9800-001 - Manual (Page 4)

TABLE OF CONTENTS (CONT’D)
iii
February 2001
Part No. 001-9800-001
TABLE OF CONTENTS
3.10 SYNTHESIZER CIRCUIT DESCRIPTION
(800/900 MHz MODELS) . . . . . . . . . . . . . . . 3-22
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-22
Voltage-Controlled Oscillator . . . . . . . . . . . . . 3-22
VCO and TCXO Modulation . . . . . . . . . . . . . . 3-24
Active Filter (Q800) . . . . . . . . . . . . . . . . . . . . . 3-25
Buffer Amplifier (Q801), Tx/Tx Switch
(CR801/CR802) . . . . . . . . . . . . . . . . . . . . . . 3-25
Synthesizer Integrated Circuit (U804) . . . . . . . 3-26
Lock Detect . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-27
Charge Pump . . . . . . . . . . . . . . . . . . . . . . . . . . 3-27
Shift Register (U800, U801) and Digital
Potentiometer (U802) Programming . . . . . . 3-27
3.11 RECEIVER CIRCUIT DESCRIPTION
(800/900 MHz MODELS) . . . . . . . . . . . . . . . 3-27
Front End Filter . . . . . . . . . . . . . . . . . . . . . . . . 3-27
RF Amplifier (Q201) . . . . . . . . . . . . . . . . . . . . 3-27
First Mixer (Q202), Crystal Filter (Z204) . . . . 3-28
Second Mixer/Detector (U201) . . . . . . . . . . . . 3-28
3.12 TRANSMITTER CIRCUIT DESCRIPTION
(800/900 MHz MODELS) . . . . . . . . . . . . . . . 3-29
Predriver (Q506), Driver (Q507) . . . . . . . . . . . 3-29
Power Amplifier Module (U600), Final (Q651) 3-30
Antenna Switch . . . . . . . . . . . . . . . . . . . . . . . . 3-30
Directional Coupler, Low-Pass Filter. . . . . . . . 3-30
Power Control (U500A/B, Q500-Q503) . . . . . 3-31
4 SERVICING
4.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Periodic Checks . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Schematic Diagrams and Component Layouts. . 4-1
Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . 4-1
Configuring Transceiver for Testing . . . . . . . . . 4-1
4.2 SURFACE MOUNTED DEVICES (SMDs) . . 4-1
Servicing Techniques . . . . . . . . . . . . . . . . . . . . . 4-1
Identifying SMD Resistors . . . . . . . . . . . . . . . . . 4-1
SMD Capacitor Identification . . . . . . . . . . . . . . 4-2
SMD Inductor Identification . . . . . . . . . . . . . . . 4-3
Transistor/Diode Identification . . . . . . . . . . . . . 4-3
4.3 SYNTHESIZER TROUBLESHOOTING . . . . 4-3
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Reference Oscillator (U806). . . . . . . . . . . . . . . . 4-4
VCO Module . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Synthesizer IC (U804) . . . . . . . . . . . . . . . . . . . . 4-4
Determining Synthesizer Counter Divide
Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
4.4 RECEIVER SERVICING . . . . . . . . . . . . . . . . . . 4-5
4.5 TRANSMITTER SERVICING . . . . . . . . . . . . . 4-5
4.6 AUDIO/LOGIC BOARD SERVICING . . . . . . . 4-5
Digital Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
Analog Circuits. . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
5 PARTS LIST
Front Panel Assembly and Mechanical Parts . . . 5-1
UHF RF and PA Boards . . . . . . . . . . . . . . . . . . . 5-3
800/900 MHz RF and PA Boards . . . . . . . . . . . 5-18
Audio/Logic Board . . . . . . . . . . . . . . . . . . . . . . 5-25
9800-Series Radio Mounting Kit . . . . . . . . . . . 5-30
9800-Series Remote Mounting Kit . . . . . . . . . . 5-30
DC Power Cable and Hardware Kit . . . . . . . . . 5-30
Accessory Wire Kit . . . . . . . . . . . . . . . . . . . . . . 5-30
Amplified Dynamic Microphone . . . . . . . . . . . 5-30
15 Watt, 4.7-Ohm Speaker (Black) . . . . . . . . . . 5-30
Exploded Views
Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . . 5-31
Front and Top . . . . . . . . . . . . . . . . . . . . . . . . 5-32
Bottom. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-32
Remote Control Unit . . . . . . . . . . . . . . . . . . . 5-33
Remote Transceiver . . . . . . . . . . . . . . . . . . . 5-33
6 SCHEMATIC DIAGRAMS AND
COMPONENT LAYOUTS
Amplified Dynamic Microphone . . . . . . . . . . . . 6-2
Transceiver Top Photo . . . . . . . . . . . . . . . . . . . . 6-3
Transceiver Bottom Photo. . . . . . . . . . . . . . . . . . 6-3
Interconnect Schematic. . . . . . . . . . . . . . . . . . . 6-4
Interface Board Layout. . . . . . . . . . . . . . . . . . . 6-4
Display Board
Top View. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Bottom View . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
RPI (P.N. 023-9800-000)
Board Layout. . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Programming Cable (P.N. 597-2002-200) . . . 6-6
Component Locator Guides
UHF RF Board . . . . . . . . . . . . . . . . . . . . . . . . 6-7
800/900 MHz RF Board . . . . . . . . . . . . . . . . 6-10
Audio/Logic Board . . . . . . . . . . . . . . . . . . . . 6-12
430-470 MHz RF
RF Board Schematic (Revised Board . . . . . . 6-15
PA Board Schematic (25W) . . . . . . . . . . . . . 6-15
RF Board Layout (Revised Board) . . . . . . . . 6-16
VCO Board Layout . . . . . . . . . . . . . . . . . . . . 6-17
PA Board Layout (25W) . . . . . . . . . . . . . . . . 6-17
PA Board Schematic (40W) . . . . . . . . . . . . . 6-18
PA Board Layout (40W) . . . . . . . . . . . . . . . . 6-19
RF Board Schematic (Unrevised Board) . . . 6-20
RF Board Layout (Unrevised Board) . . . . . . 6-21