BAOJIE BJ-9900 User Manual

QUANZHOUBAOJIE ELECTRONICS CO.,LTD. Model:BJ-9900
Version:BJ-9900-0812-V1 Page 1 of 75
Dual Band FM Transceiver
BJ-9900
SERVICE MANUAL
----------------------CONTENTS--------------------
INTRODUCTION……………………………………………………….……….2
PERSONAL SECURITY………………………………….….………….…..…2
CIRCUIT DESCRIPTION………………….………………………….………..3
BLOCK DIAGRAM……………………………………………………...…..…13
Board Unit (Schematics, Layouts & Parts)
Display Unit……………………….………………..………………….14
TX-RX Unit………………………….…….…………………………….21
Panel Unit……………………………………………………………….68
Panel-Sub Unit…………………………………………………..….….71
VR-L/R Unit……………………………………………………………..73
SPECIFICATION………………………………………………….…………….75

BAOJIE BJ-9900 Specifications

General

Power Output	25W/10W/5W
Channel Capacity	200
Operating Voltage	13.8V DC ±15%
Frequency Range	400-470MHz
Channel Spacing	25 kHz

Summary

INTRODUCTION

Scope of this manual

Provides necessary technical information for the maintenance and inspection of mobile radio BJ-9900.

Personal Security

Safety tips for personal protection during operation and maintenance of the radio equipment.

CIRCUIT DESCRIPTION

Receiver Signal Channel

Details the signal path for receiving VHF and UHF signals, including mixers and IF stages.

Squelch Control

Describes the squelch control mechanism for both main and sub bands.

Transmitter Signal Channel

Explains the signal path for transmitting VHF and UHF signals, including modulation and power amplification.

Automatic Power Control Circuit

Explains the circuit responsible for maintaining stable output power during transmission.

PTT Electric Circuit

Describes the Push-To-Talk (PTT) electrical circuit operation.

PLL Electric Circuit

Details the Phase-Locked Loop (PLL) circuitry for frequency synthesis.

BLOCK DIAGRAM

TX-RX Unit Block Diagram

Block diagram of the Transmit-Receive unit, showing key functional blocks.

Display Unit Block Diagram

Block diagram of the Display Unit, illustrating its components and connections.

Panel-Sub Unit Block Diagram

Block diagram of the Panel-Sub Unit, detailing its functional blocks.

VR-L/R Unit Block Diagram

Block diagram for the Volume/Squelch Left/Right unit.

Display Unit Schematics

Display Unit Schematics

Detailed schematic diagram for the Display Unit.

Display Unit Layouts

Physical layout of components on the Display Unit PCB.

Display Unit Parts List

List of components used in the Display Unit with their specifications.

TX-RX Unit Schematics

TX-RX Unit Schematics

Detailed schematic diagram for the TX-RX Unit.

TX-RX Unit Layouts

Physical layout of components on the TX-RX Unit PCB.

TX-RX Unit Parts List

List of components used in the TX-RX Unit.

Panel Unit Layouts

Panel Unit Layouts

Physical layout of components on the Panel Unit PCB.

PANEL-Sub Unit Schematics

Detailed schematic diagram for the Panel-Sub Unit.

PANEL-Sub Unit Layouts

Physical layout of components on the Panel-Sub Unit PCB.

Panel-Sub Unit Parts List

List of components used in the Panel-Sub Unit.

VR-L/R Unit Schematics

VR-L/R Unit Schematics

Detailed schematic diagram for the VR-L/R Unit.

VR-L/R Unit Layouts

Physical layout of components on the VR-L/R Unit PCBs.

VR-L/R UNIT Parts List

List of components used in the VR-L/R Unit.

SPECIFICATION

General Specification

Overall technical specifications including frequency range, modulation, and dimensions.

Transmitter Specifications

Detailed output power, modulation type, and spurious radiation for transmission.

Receiver Specifications

Detailed sensitivity, selectivity, and audio output specifications for reception.