User ManualTable of ContentsIMPORTANT MAINTENANCE/REPAIR INFORMATION4Surface Mount Repair4Precautions for Handling CMOS Devices4PC Board Removal - Special Tool4Properly Attach the Synthesizer Shield4Re-assembly - Speaker Magnet, Battery Voltage on Connector Pin4Radio Transmitter Power Measurements4SST-444 SPECIFICATIONS5GENERAL5GENERAL6RECEIVER6L.O. Injection: Low side6SST-444 SPECIFICATIONS7TRANSMITTER7INTRODUCTION8GENERAL8FCC REGULATIONS8BATTERY CARE9CHARGING9BATTERY CARE10BATTERY REPLACEMENT10PRECAUTIONS10PTT (PUSH-TO-TALK) PROGRAMMING18Table 1 – PTT Programming Frequency Table20Table 2 – Quiet Call Codes and Frequencies20PROGRAMMING THE RADIO USING A PC COMPUTER21INTRODUCTION23POWER SUPPLY AND VOLTAGE DISTRIBUTION23Power Strobe23Low Battery Voltage Detection23REFERENCE OSCILLATOR24SYNTHESIZER24Pin Numbers24Prescaler Divider / Synthesizer Controller24VCO / Buffer Amplifiers25Oscillator Modulation25DIGITAL POTENTIOMETERS25RECEIVER26RF Amplifier26FM Receiver Subsystem26Voice / Tone Conditioning in Receive Mode26Voice Band27Sub-Audible27Audio Amplifier27ANTENNA SWITCHING / LOW PASS FILTER27TRANSMITTER28MICROCONTROLLER29SST-444 SCHEMATIC REFERENCE PARTS LIST41SST-444 SCHEMATIC REFERENCE PARTS LIST42SST-444 SCHEMATIC REFERENCE PARTS LIST43SST-444 SCHEMATIC REFERENCE PARTS LIST44SST-444 SCHEMATIC REFERENCE PARTS LIST45SST-444 SCHEMATIC REFERENCE PARTS LIST46SST-444 SCHEMATIC REFERENCE PARTS LIST47SST-444 CASE ASSEMBLY PARTS LIST48Size: 293 KBPages: 48Language: EnglishOpen manual
