User ManualTable of ContentsTABLE OF CONTENTS2SPECIFICATIONS4GENERAL4TEMPERATURE RANGE4CURRENT CONSUMPTION4FREQUENCY BANDS5DIMENSIONS5WEIGHT5TRANSMITTER5AUDIO FREQUENCY DEVIATION5ADJACENT CHANNEL POWER5RECEIVER6RX TONE DEMODULATION CHARACTERISTICS7INTRODUCTION8FEATURES8Main Features8Wideband8Scan Mode8Scan Channel Delete8Scan Delay Time9Busy Channel Lockout9Marked Idle Enable9Normal/Inverted DCS9Standard/Non-Standard CTCSS9Transmit Time-Out-Timer (TOT)/TX Inhibit9VCO Lock Time10Low Battery Indication10Memory Protect10External Option Detect10DESCRIPTION OF CONTROLS11THEORY OF OPERATION12DIGITAL CIRCUITS12CTCSS/DCS Decode Circuits12CTCSS/DCS Encoder Circuit12External Mic/PTT Control Circuit12Channel Select Circuit12Low Battery Indicator Circuit12EEPROM12High Pass Filter12Mute (squelch) Circuit13TX Audio And Filter Circuits13Analog Ground Supply13Audio Mixer And Inverter13Monitor13RF CIRCUITS13Transmitter13Buffer13P.A. Module13Low Pass Filter13Antenna Switch13Automatic Power Control (APC) Circuits13RF CIRCUITS PLL SYNTHESIZER1412.8 MHz TCXO14PLL IC Dual Modules Prescaler14Level Shifter & Charge Pump14Reference Frequency LPF14DC to DC Converter14VCO14RECEIVER14Front End14First Mixer14Second Oscillator Mixer Limiter And FM Detector14Squelch (mute) Circuit1516 kHz Band Pass Filter15Noise Detector15Low Pass Filter15Speaker Audio Amplifier15MAINTENANCE AND REPAIR16GENERAL16REMOVING & REPLACING THE BELT CLIP16Removing the belt clip:16To replace the belt clip:16REMOVING & REPLACING THE BATTERY17To remove the battery:17To replace the battery:17REMOVING & REPLACING PTT ASSY.17To remove the PTT assembly:17To replace the PTT assembly:18REMOVING & REPLACING THE ACCESSORY CONNECTOR18To remove the Accessory Connector:18To replace the Accessory Connector:18REMOVING & REPLACING THE ANTENNA & CONTROL KNOBS18To remove the Antenna:18To replace the Antenna:18To remove the Control Knobs:18To replace the Control Knobs:18REMOVING & REPLACING THE BACK COVER19To remove the Back Cover:19To replace the Back Cover:19REMOVING & REPLACING THE MAIN BOARD20To remove the Main Board:20To replace the Main Board21REMOVING & REPLACING THE DAUGHTER BOARDS22To Replace a Daughter Board:22REMOVING & REPLACING THE SPEAKER22To remove the speaker:22To replace the speaker22COMPONENT REPLACEMENT22Surface Mount Components22Surface Mount Removal22Surface Mount Component Replacement23Surface Mounted Integrated Circuit Replacement23PROGRAMMING24Cloning24ALIGNMENT PROCEDURE24SQUELCH ADJUSTMENT24RX VCO25RECEIVER25TRANSMITTER25TCXO25TX VCO25CTCSS, DCS & DEVIATION ALIGNMENT25APC25TEST EQUIPMENT SETUP26ALIGNMENT POINTS DIAGRAM27ALIGNMENT POINTS VHF & UHF WITH TCXO MODULE27ALIGNMENT POINTS UHF WITH OUT TCXO MODULE27VOLTAGE CHARTS29SP-300 SERIES UHF & VHF DIGITAL SECTION PARTS LIST32SP-300 SERIES VHF RF SECTION PARTS LIST34SP-300 SERIES UHF RF SECTION PARTS LIST37COMPONENT PINOUT41SCHEMATICS & BLOCK DIAGRAM44VHF FRONT-END44VHF POWER AMP44UHF POWER AMP44UHF FRONT-END44UHF V.C.O.45VHF V.C.O.45TCXO46ACC-200 BATTERY46FUSE46P.T.T.46Digital Schematic47VHF RF Schematic48UHF RF Schematic49Block Diagram50PCB LAYOUTS51Exploded View52Size: 3.44 MBPages: 52Language: EnglishOpen manual