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tti Tech PMR-446 Service Manual

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PMR-446 Radio
TX-446
TTI Tech

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Summary of Contents for tti Tech PMR-446

  • Page 1 PMR-446 Radio TX-446 TTI Tech...

  • Page 2: Table Of Contents

    TABLE OF CONTENTS SECTION SPECIFICATIONS SECTION INSIDE VIEWS SECTION CIRCUIT DESCRIPTION MICROPROCESSOR / CONTROL SECTION VCO / SYNTHESIZER SECTION TRANSMITTER SECTION RECEIVER SECTION BATTERY SECTION SECTION ADJUSTMENT PROCEDURES GENERAL SYNTHESIZER / TRANSMITTER TRANSMITTER ALIGNMENT RECEIVER ALIGNMENT SECTION PART LIST ELECTRICAL PART LIST MECHANICAL PART LIST SECTION MECHANICAL DISASSEMBLY...

  • Page 3: Specifications

    SECTION 1 SPECIFICATIONS Parameter Specification Number of Channels 8 ch Frequency Range 446.00625 - 446.09375 MHZ Channel Specing 12.5 MHZ Channel Increments 6.25 KHZ Size (W x D x H) 132 x 56 x 36 mm Weight (With Battery and Antenna) 400 g Battery Voltage 7.5 V, Nominal...

  • Page 4: Inside Views

    SECTION 2 INSIDE VIEWS CV301 (Frequency ADJ.) RV101 (CTCSS, DCS Devation ADJ.) RV503 (CTCSS, DCS Blance ADJ.) RV501 (VCO Lock Voltage Detect) (MOD ADJ.) TX-446 ADJUSTMENT POINT...

  • Page 5: Circuit Description

    SECTION 3 CIRCUIT DESCRIPTION GENERAL INFORMATION The TX-446 has four printed circuit boards. (Main PCB, SW PCB and two BATT PCB in battery pack.) Circuitry is described in the following order: Microprocessor/Control Section, VCO/Synthesizer Section, Transmitter Section, Receiver Section and Battery Section. Refer to the Block Diagram and the Schematics. MICROPROCESSOR / CONTROL SECTION The microprocessor Q106 is constantly operating when the radio is turned ON.

  • Page 6: Transmitter Section

    TRANSMITTER SECTION RF POWER Amplifier The transmitter parts of the TX-446 is designed to amplify the RF signal oscillated and modulated by the synthesizer to approximately 500mW by the power transistor of Q407. The transmitted signal of approximately 7mW, combined at the driver FET is supplied to the gate of the Q407 amplifier. The transmitted signal amplifier to 500mW here passes the TX LPF of the second characteristics of the C418-C421, L408, PCB_L1 and PCB_L2 and RX/TX switching takes place by the Q406.

  • Page 7: Receiver Section

    RECEIVER SECTION Receiver Front End In the receive mode, the RF signal enters thorough the antenna, then through the low-pass filter C427, C428, C430, C432 and L412, L413, L414 . The diodes Q404 and Q406 are biased off so that the output of the low-pass filter is, coupled (C401) to the Front End RF overload protection diode pair Q401 and the first band-pass filter SAW401.

  • Page 8: Adjustment Procedures

    SECTION 4 ADJUSTMENT PROCEDURES 4-1. GENERAL For proper alignment, the unit should be programmed with the following channel and frequency information. RX (MHz) TX (MHz) RX/TX Tone Code CH01 446.00625 446.00625 No Tone CH02 446.01875 446.01875 No Tone CH03 446.03125 446.03125 No Tone CH04...

  • Page 9: Transmitter Alignment

    4-2-4. VOX Adjustment 1. Place the Radio on channel 4 (446.04375MHz). 2. Adjust by hardware parameter setting function of CPS (Computer Programming System). 3. Adjust VOX Sensitivity High first. 4. Operate the transmitter and establish audio level so that deviation becomes 0.6KHz.

  • Page 10: Receiver Alignment

    4-4. RECEIVER ALIGNMENT 4-4-1. Receiver sensitivity confirmation 1. Connect the Radio in accordance with Figure 3. 2. Set the output level of the RF signal generator for -47dBm and 1.5KHz deviation of 1KHz tone. 3. Set the audio output for 0.6V Vrm by adjusting volume. 4.
  • Page 11 [Figure 1] DVM (DC) Spectrum Analyzer Audio SG Program Jig Transceiver Dummy Load Frequency Counter FM Detector PC (CPS) DC Power Supply (7.5V) Digital Oscilloscope [Figure 2] PC (CPS) Program Jig Transceiver Power Meter Ant Jack DC Ammenter DC Power Supply (7.5V) [Figure 3] RF SG...

  • Page 12: Part List

    SECTION 5 PART LIST 5-1. ELECTRICAL PART LIST Ref. No. Part Type Description C101 No Mount C103 Chip Capasitor 0.001 C104 Chip Capasitor 0.001 C105 Chip Capasitor 0.001 C107 Chip Capasitor 0.001 C109 Chip Capasitor 0.001 C111 Chip Capasitor 0.001 C112 Tantalum elec.
  • Page 13 C319 Chip Capasitor C320 Tantalum elec. chip cap. 1u16V(T) C321 Chip Capasitor 100p C322 Chip Capasitor 100p C323 Chip Capasitor 100p C324 Chip Capasitor 22pUJ C325 Chip Capasitor 100p C326 Chip Capasitor 0.01 C327 Chip Capasitor C328 Chip Capasitor 220p C329 Chip Capasitor 33pUJ...
  • Page 14 C435 Chip Capasitor 0.0033 C436 Chip Capasitor 220p C437 Chip Capasitor C438 Chip Capasitor 0.01 C439 Chip Capasitor 0.001 C440 Chip Capasitor C441 Chip Capasitor C442 Chip Capasitor C443 Chip Capasitor 0.001 C444 Chip Capasitor 0.001 C445 Chip Capasitor 0.001 C446 Chip Capasitor 100p...
  • Page 15 C536 Chip Capasitor C537 Chip Capasitor C538 Chip Capasitor 220p C539 Chip Capasitor C540 Chip Capasitor 0.0047 C541 Chip Capasitor 0.022 C542 Chip Capasitor 100p C543 Chip Capasitor 0.068 C544 Chip Capasitor 0.01 C545 Chip Capasitor 0.022 C546 Chip Capasitor C547 Chip Capasitor 0.0068...
  • Page 16 Q101 SLM-020MLT Q106 M38223M4M-HP Q107 No Mount Q108 Digital Transistor KRC404 Q109 24WC04J Q110 Digital Transistor KRC404 Q111 Digital Transistor KRC404 Q201 Digital Transistor KRA226S Q202 Digital Transistor KRA226S Q203 Digital Transistor KRA225S Q204 Digital Transistor KTC601E Q205 Digital Transistor KRA404 Q206 Zener diode...
  • Page 17 R101 Chip Resistor 100K R102 Chip Resistor R103 Chip Resistor 5.1K R104 Chip Resistor 5.1K R105 Chip Resistor R106 Chip Resistor 5.1K R107 Chip Resistor 5.1K R108 Chip Resistor 5.1K R109 Chip Resistor R110 Chip Resistor R111 Chip Resistor 5.1K R112 Chip Resistor R113...
  • Page 18 R319 Chip Resistor R320 Chip Resistor 100K R321 Chip Resistor R322 Chip Resistor R323 Chip Resistor R324 Chip Resistor R325 Chip Resistor R326 Chip Resistor R327 Chip Resistor R328 Chip Resistor R329 Chip Resistor R330 Chip Resistor R331 Chip Resistor R332 Chip Resistor R333...
  • Page 19 R438 Chip Resistor 2.2K R439 Chip Resistor R440 Chip Resistor 100K R441 Chip Resistor R442 No Mount R443 Chip Resistor R444 Chip Resistor R445 Chip Resistor 4.7K R501 Chip Resistor R502 Chip Resistor R503 Chip Resistor 470K R504 Chip Resistor 820K R505 No Mount...
  • Page 20 R555 Chip Resistor 820K R556 Chip Resistor 4.7K R557 Chip Resistor R558 Chip Resistor 2.2K R559 Chip Resistor 4.7K R560 Chip Resistor R561 Chip Resistor 5.36K R562 Chip Resistor 430K R701 Chip Resistor 4.7K R702 Chip Resistor R703 Chip Resistor R706 Chip Resistor R707...

  • Page 21: Mechanical Disassembly

    SECTION6 MECHANICAL DISASSEMBLY NO TYPE PART DESCRIPTION PC (B) FRONT CASE SILICON BUTTON PTT PC (B) COVER PTT FRLT t0.3 FELT SPEAKER NR-04005NB SPEAKER SILICONE LENS LED BsBm Cr-PLATE RING GND ACETAL SPACER ANT BsBM Cr-PLATE NUT ANT 10 SILICONE GASKET VOLUME 11 SK5 t0.25 D-SPRING...

  • Page 22: Board Layout

    SECTION 7 BOARD LAYOUT 7-1 MAIN PCB (Top side) XF401 PC-4083 Parts Placement: TX-446 Top side Date: MAR 26, 2003 Up Date: APR 11, 2003 Drawing No.: E23-00390A APR: CHK: DRW:...
  • Page 23 (Bottom side) R340 L304 C313 R307 R311 SAW401 CN204 R427 C340 CN203 J201 PC-4083 Parts Placement: TX-446 Bottom side Date: MAR 26, 2003 Up Date: MAR 26, 2003 Drawing No.: E23-00391A APR: CHK: DRW:...
  • Page 24 (Inner Layer 1) PC-4083 TX-446 Inner Layer 1 Date: MAR 26, 2003 Up Date: MAR 26, 2003 Drawing No.: E23-00392A APR: CHK: DRW:...
  • Page 25 (Inner Layer 2) PC-4083 TX-446 Inner Layer 2 Date: MAR 26, 2003 Up Date: MAR 26, 2003 Drawing No.: E23-00393A APR: CHK: DRW:...

  • Page 26: Switch Pcb

    7-2 SWITCH PCB (Top side) Parts Placement: TX-446 SW PCB Top side Date: MAR 26, 2002...
  • Page 27 (Bottom side) Parts Placement: TX-446 SW PCB Bottom side Date: MAR 26, 2003...

  • Page 28: Battery Pcb

    7-3 BATTERY PCB (A Top side) Parts Placement: TX-446 BATT PCB A Top side Date: MAR 26, 2003...
  • Page 29 (A Bottom side) WB104 WB103 Parts Placement: TX-446 BATT PCB A Bottom side Date: MAR 26, 2003...
  • Page 30 (B Top side) Parts Placement: TX-446 BATT PCB B Top side Date: MAR 26, 2003...
  • Page 31 (B Bottom side) WB105 RB101 WB102 Parts Placement: TX-446 BATT PCB B Bottom side Date: MAR 26, 2003...

  • Page 32: Block Diagram

    CONTROL MONITOR SWITCH INTERNAL 4.19MHz CHANNEL EEPROM CLOCK SELECTOR EXTERNAL OSCILLATOR MICROPHONE AC/DC VOX LEVEL OUT CONVERT Title TX-446 BLOCK DIAGRAM TTI Tech Co., Ltd. Size: Number: E72-00027Z Revision: File: Date: APR 22, 2003 Time: Sheet Nakamura Drw: Chk: Apr:...

  • Page 33: Circuit Diagram

    Q207 4.7K KRA305 2SK508 C207 E201 PC-070 SW PCB SSM3K03FE CN102 CMP-4542 EXT_PTT PC-4083 Title TTI Tech Co., Ltd. TX-446 Schematic Rm402 EUNDO BLDG, 737-19 BANPO-1DONG, SEOCHO-KU, SEOUL 137-041, Size: Number: E12-00099A Revision: KOREA File: Date: APR 19, 2003 Time:...

  • Page 34: Battery Pcb

    9-2 BATTERY PCB (To Set) CB101 0.01 BB101 GP130AAM6SXZ RB101 10K TH (To Chager) Title TX-446 Battery TTI Tech Co., Ltd. Size: Number: Revision: File: Date: MAY 7, 2002 Time: Sheet Drw: K.Nakamura Chk: Apr:...

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