Icom IC-F70DT Service Manual
  1. Manuals
  2. Brands
  3. Icom Manuals
  4. Transceiver
  5. IC-F70DT
  6. Service manual

Icom IC-F70DT Service Manual

Hide thumbs Also See for IC-F70DT:
Table of Contents

Advertisement

Quick Links

Download this manual See also: Instruction Manual, Operating Manual
SERVICE
MANUAL
VHF TRANSCEIVER

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the IC-F70DT and is the answer not in the manual?

Questions and answers

Subscribe to Our Youtube Channel

Related Manuals for Icom IC-F70DT

Summary of Contents for Icom IC-F70DT

  • Page 1 SERVICE MANUAL VHF TRANSCEIVER...
  • Page 2 8. READ the instructions of test equipment thoroughly before connecting equipment to the transceiver. Icom, Icom Inc. and are registered trademarks of Icom Incorporated (Japan) in the United States, the United Kingdom, Germany, France, Spain, Russia and/or other countries.

  • Page 3: Table Of Contents

    DIGITAL CIRCUIT (IC-F70DT/DS only) ........

  • Page 4: Specifications

    : 50 Ω (Nominal) • Antenna impedance • Operating temperature range : −22°F to 140°F • Power supply requirement : Specified Icom's battery pack only (Operatable voltage; 7.2 V DC negative ground) • Current drain (At 7.2 V DC ; approx.) RECEIVING TRANSMITTING Stand-by Max.audio...

  • Page 5: Inside Views

    FM IF IC (IC3: TA31136FN) (IC3: TA31136FN) Audio processor Audio processor DSP unit DSP unit (IC301: AK2346) (IC301: AK2346) [IC-F70DS/DT] only [IC-F70DT/DS] only Digital/Analog switch Digital/Analog switch Decode IC DTMF DECODE (IC302: BU4053BCFV) (IC302: BU4053BCFV) (IC300: LC73872M) (IC300: LC73872M) EEPROM...

  • Page 6: Disassembly Instructions

    SECTION 3 DISASSEMBLY INSTRUCTIONS • REMOVING THE CHASSIS UNIT • REMOVING THE MAIN UNIT 1 Unscrew the ANT nut A and remove the ANT washer B. 1 Disconnect the cable H from J3. 2 Unscrew the screw C, and remove the rear panel D in 2 Remove the DSP unit from J2.

  • Page 7: Circuit Description

    SECTION 4 CIRCUIT DESCRIPTION 4-1 RECEIVER CIRCUITS The signals from the two-stage tunable BPF are converted into the 46.35 MHz 1st IF signal at the double-balanced 4-1-1 ANTENNA SWITCHING CIRCUIT type 1st mixer (IC14, L30, L31, L33) by being mixed with The antenna switching circuit toggles the receive line and the 1st LO signal generated at the RX VCOs (Q4, D4, D5, the transmit line.
  • Page 8 The quadrature detector is a detection method which uses a demodulated AF signals, the squelch circuit switches the ceramic discriminator (X2). AF mute swithch and AF power amplifier controller ON and OFF. The demodulated AF signals are output from pin 9, and applied to the AF cricuits.

  • Page 9: Transmitter Circuits

    4-2 TRANSMITTER CIRCUITS The CTCSS/DTCS signals are generated by the CPU (IC307) 4-2-1 MICROPHONE AMPLIFIER CIRCUIT and output from pins 89–91 (“CENC0,” “CENC1,” ”CENC2”). The microphone amplifier circuit amplifies the audio signals The CTCSS/DTCS signals are passed through 3 regis- from microphone within +6 dB/oct pre-emphasis characteris- ters (R374–R376) to change its wave form.

  • Page 10: Pll Circuits

    4-3 PLL CIRCUITS A portion of the signal from the buffer amplifier (Q6) is fed 4-3-1 PLL CIRCUIT (MAIN UNIT) back to the PLL IC (IC1, pin 6) via the buffer amplifier (Q9) The PLL circuit provides stable oscillation of the transmit and the BPF (Q1, D1, D2, L2, L56, L57, L302, C12, C15, frequency and receive 1st LO frequency.

  • Page 11: Digital Circuit (Ic-F70Dt/Ds Only)

    4-5 DIGITAL CIRCUIT (IC-F70DT/DS only) The audio signals from the DSP UNIT are applied to the base band IC (MAIN UNIT; IC301, pin 20) after being • WHILE RECEIVING passed through the digital/analog switch (MAIN UNIT; IC302 ). A portion of the 2nd IF sigal from the limiter amplifier section in the FM IF IC (IC3) is output from pin 11 and is applied to •...
  • Page 12 4-6-1 CPU (continued) Port Description number name Port Description number name CENC0– 89–91 Output the CTCSS/DTCS signals. CENC2 Input port for the noise signal from NOIS the FM IF IC (IC3, pin 13). Input port for [MONITOR] switch (MAIN SIDE3 UNIT;...

  • Page 13: Adjustment Procedures

    : Wide 155.000 MHz Microsoft and Windows are registered trademarks of CTCSS : 151.4 Hz Microsoft Corporation in the U.S.A. and other countries. TX power : Low1 155.000 MHz Mode : Narrow *; IC-F70DT/DS only †; [USA-02] only 5 - 1...
  • Page 14 • CONNECTION • JIG cable 5 - 2...
  • Page 15 • PC SCREEN EXAMPLE NOTE: The above values for settings are example only. Each transceiver has its own specific values for each setting. @1 : S-meter q: Reload adjustment data !1 : Receive sensitivity for center (automatic) @2 : S-meter (digital) w: Transceiver's connection state !2 : Receive sensitivity for center (manual) @3 : Deviation (narrow)

  • Page 16: Software Adjustment

    BASE BAND • Operating CH. : CH 9 Set the "Dig DA" item to 70. CENTER • Receiving screen VOLTAGE* [Dig DA] *; IC-F70DT/DS only MAIN UNIT DSP UNIT DSP REFERENCE FREQUENCY IC-13, pin 4) CHECK POINT ( 5 - 4...
  • Page 17 SOFTWARE ADJUSTMENT (Continued) Select an operation using [↑] / [↓] keys, then set specifi ed value using [←] / [→] keys on the connected computer keyboard MEASUREMENT ADJUSTMENT ADJUSTMENT CONDITION VALUE UNIT OPERATION OUTPUT 1 • Operating CH. : CH 3 Connect an RF power meter to 5.0 W POWER...
  • Page 18 • No audio applied to the JIG cable. panel the antenna connector through DEVIATION an attenuator. • Set an FM deviation meter as; [S.Tone] : OFF : 20 kHz De- emphasis : OFF Detector : (P–P)/2 • Push [P3] while transmitting. *; [IC-F70DT/DS] only 5 - 6...
  • Page 19 Level : –14dBµ (–121 dBm) just appears. Modulation : 1 kHz : ±3.5 kHz Deviation • Receiving *; [IC-F70DT/DS] only †; The output level of the standard signal generator (SSG) is indicated as the SSG's open circuit. 5 - 7...

  • Page 20: Parts List

    SECTION 6 PARTS LIST [MAIN UNIT] [MAIN UNIT] ORDER ORDER DESCRIPTION DESCRIPTION LOCATION LOCATION 1130010100 S.IC LMX2352TMX 8.3/75.8 1790001250 S.DIO MA2S111-(TX) 26.2/105.3 1110005340 S.IC NJM12902V-TE1 8/75.7 D301 1160000050 S.DIO DAP202U T106 33.6/26 1110003490 S.IC TA31136FN 14.6/57.6 D302 1160000050 S.DIO DAP202U T106 32.4/5.4 1190002050 S.IC SPM5001...
  • Page 21 [MAIN UNIT] [MAIN UNIT] ORDER ORDER DESCRIPTION DESCRIPTION LOCATION LOCATION 7030009270 S.RES ERJ2GEJ 821 X (820 Ω) L302 6200011250 S.COL LLQ1608-A18NG 12.9/92.7 24.1/74.2 7030004970 S.RES ERJ2GEJ 470 X (47 Ω) 27.6/75.8 7030004980 S.RES ERJ2GEJ 101 X (100 Ω) 34.9/76.2 7030009270 S.RES ERJ2GEJ 821 X (820 Ω) 7030005050 S.RES ERJ2GEJ 103 X (10 kΩ) 5.8/71.2 31.2/89.9...
  • Page 22 [MAIN UNIT] [MAIN UNIT] ORDER ORDER DESCRIPTION DESCRIPTION LOCATION LOCATION R349 7030005160 S.RES ERJ2GEJ 105 X (1 MΩ) 32.5/15.8 R447 7030005050 S.RES ERJ2GEJ 103 X (10 kΩ) 21.9/29.2 R350 7410001140 S.ARY EXB28V104JX 35/4.4 R448 7030005090 S.RES ERJ2GEJ 104 X (100 kΩ) 30.1/25.1 R351 7030008410 S.RES ERJ2GEJ 392 X (3.9 kΩ)
  • Page 23 [MAIN UNIT] [MAIN UNIT] ORDER ORDER DESCRIPTION DESCRIPTION LOCATION LOCATION 4030017380 S.CER ECJ0EC1H050B 23/101.3 C175 4030017490 S.CER C1608 JB 1A 105K-T 35.2/96.2 C176 4030017420 S.CER ECJ0EC1H470J 39/91.8 4030016790 S.CER ECJ0EB1C103K 25/103.7 4030017460 S.CER ECJ0EB1E102K 19.4/103.3 C177 4030017460 S.CER ECJ0EB1E102K 39.3/86 4030017640 S.CER ECJ0EC1H150J 16.4/101.7 C178...
  • Page 24 [MAIN UNIT] [MAIN UNIT] ORDER ORDER DESCRIPTION DESCRIPTION LOCATION LOCATION C335 4030017720 S.CER ECJ0EB1H331K 17/32.4 C435 4030017420 S.CER ECJ0EC1H470J 32.3/9.8 C436 4030017420 S.CER ECJ0EC1H470J 32/10.7 C336 4030016930 S.CER ECJ0EB1A104K 25.9/69.8 C337 4030016940 S.CER ECJ0EB1A393K 11.2/79.1 C437 4030017420 S.CER ECJ0EC1H470J 34.6/11.6 C338 4030017760 S.CER ECJ0EB1H222K 19.2/29.6...

  • Page 25: Front Unit

    4030016790 S.CER ECJ0EB1C103K 22/86.1 7030005090 S.RES ERJ2GEJ 104 X (100 kΩ) 4030009580 S.CER C1608 JB 1H 681K-T 26.9/38.1 [IC-F70DT/T] only B 16.4/79.1 4030009580 S.CER C1608 JB 1H 681K-T 28.8/32.6 7030005090 S.RES ERJ2GEJ 104 X (100 kΩ) 4030009580 S.CER C1608 JB 1H 681K-T 30/33.4...
  • Page 26 [FRONT UNIT] [DSP UNIT] (IC-F70DT/DS only) ORDER ORDER DESCRIPTION DESCRIPTION LOCATION LOCATION C225 4030016930 S.CER ECJ0EB1A104K 29.8/40.2 1180002590 S.REG XC6204B332MR 2.1/19.5 1180002740 S.REG R1230D151F-TR-F 2.9/30.3 C226 4550006080 S.TAN TEESVB2 1C 106M8L 34.9/42.7 C229 4030017460 S.CER ECJ0EB1E102K 5.1/77 1180002590 S.REG XC6204B332MR 23.7/7.5...
  • Page 27 [DSP UNIT] (IC-F70DT/DS only) [DSP UNIT] (IC-F70DT/DS only) ORDER ORDER DESCRIPTION DESCRIPTION LOCATION LOCATION 7030004970 S.RES ERJ2GEJ 470 X (47 Ω) 25.7/27.1 4550007030 S.TAN TEESVP 0J 106M8R 22.4/12.6 4030017490 S.CER C1608 JB 1A 105K-T 20/17.2 7030005240 S.RES ERJ2GEJ 473 X (47 kΩ) 7.3/19.2...

  • Page 28: Main Unit

    SECTION 7 MECHANICAL PARTS AND DISASSEMBLY [MAIN UNIT] [DSP UNIT] (IC-F70DT/DS only) REF. ORDER REF. ORDER DESCRIPTION QTY. DESCRIPTION QTY. 2260002840 Switch SKHLLFA010 8930059940 Sponge (HF) 8410002530 2681 PA heatsink [FUSE BOARD] 8510016880 2803 VCO case 8510016870 2803 VCO cover REF.
  • Page 29 MP57 (C) MP51 (C) MP5 (F) Unit abbreviations (F): FRONT UNIT (M): MAIN UNIT MP51 (C) MAIN UNIT (C): CHASSIS PARTS DSP UNIT (IC-F70DT/DS only) (V): VR BOARD (D): DSP UNIT (A): ANT BOARD (F): FUSE BOARD 7 - 2...
  • Page 30 SECTION 8 SEMICONDUCTOR INFORMATION • TRANSISTORS AND FET'S • DIODES 2SA1577 T106 Q 2SB1132 T100 Q 2SC4081 T106 R 2SC4116 BL 2SC4116 Y 1SS301 1SV239 1SV284 1SV307 DAN235E TL (Symbol: HQ) (Symbol: BAQ) (Symbol: BR) (Symbol: LL) (Symbol: LY) (Symbol: B3) (Symbol: TC) (Symbol: TL) (Symbol: TX)
  • Page 31 SECTION 9 BOARD LAYOUTS 9-1 FRONT UNIT • TOP VIEW 9 - 1...
  • Page 32 • BOTTOM VIEW (FRONT UNIT) I_MIC MICROPHONE J101 VDD1 VDD2.3 to LCD (DS2) V_LCD to VR board PWRSW SPEAKER AFVI (CHASSIS SP1) XRXD RESET MICE DETECT XTXD EXPTT to MAIN unit J3 9 - 2...

  • Page 33: Fuse Board

    9-2 MAIN UNIT • TOP VIEW MONITOR DOWN BATT MP2, MP3 9-4 ANT BOARD • TOP VIEW to MAIN unit to FRONT unit J1 to Optional unit to DSP unit J1 9-3 FUSE BOARD • TOP VIEW to MAIN unit from battery pack J1(CHASSIS) 9 - 3...
  • Page 34 • BOTTOM VIEW (MAIN UNIT) • BOTTOM VIEW (ANT BOARD) • BOTTOM VIEW (FUSE BOARD) 9 - 4...

  • Page 35: Dsp Unit (Ic-F70Dt/Ds Only)

    9-5 DSP UNIT (IC-F70DT/DS only) 9-6 VR BOARD • TOP VIEW ROTARY SELECTOR VOLUME CONTROL 5V AFVI SW1_B SW2_B SW2_A POWER SW3_A CIRQ AGND DFIL FLASH_RXD AFOUT CPU_VDD TEST FLASH_TXD RMUT TEMP 3.3V BUSY AFON RSSI MMUT QOUT PTTO PTTI...

  • Page 36: Block Diagram

    DS108-DS113 IC307 IC12 DECODE HD64F2268TF NJM12902V IC300 Q202 AF_ON CR-803 DISC LC73872M SDEC 2SB1132 IC12 BEEP NJM12902V NJM12902V DSP UNIT (IC-F70DT/DS only) Q209,Q210 MUTE CDEC SIGNAL RSR025N03×2 IC201 TA7368F AFOUT DAST IC10 IC205 12.288MHz NJM2711F TC4S66F MUTE NJM12902V CR-798 BUFF...

  • Page 37: Voltage Diagrams

    SECTION 11 VOLTAGE DIAGRAMS 11-1 FRONT UNIT FRONT UNIT EXPTT EXPTT D201 R204 R216 D204 MA2S111 MA2S111 PTTI Q102 IC101 DTC144EE S-812C30AMC-C2K R101 PTT ON: 1.0V Q201 OFF: 4.9V UMG2N RESB XRXD Q103 XTXD VOUT PTTSW DTB123EK FSCL FSDA LED ON: 7.2V AFON to MAIN SPCON...

  • Page 38: Main Unit

    11-2 MAIN UNIT MAIN UNIT R26 3.9k R30 1.8k C7 47p 2SC4116 R5 560k CR-796 8.2µ 80.2n ERJ2GE-JPW 270k 2SK880 VCON 2SC4226 NJM12902V 3.3µ 1.4V 155MHz TEMP L43 3.3µ LVIN R132 3.9k R133 1.8k 2SC5107 XP1214 1.8µ 4.7k R17 4.7k LMX2352TM C223 C226...
  • Page 39 MAIN UNIT (CHASSIS) BOARD R42 100 C103 C119 5.0V C123 0.1 D23 MA2S111 R350 100k 7.2V EXCCL3225U 0.001 R121 220k R503 ERJ2GE-JPW C108 C122 C126 R125 10.5n 7.5n 0.001 0.001 0.001 C205 C207 PTTI PTTI 1SV307 PTTO PTTO TA75S01F 2SC5107 100p CPU5 CPU5...

  • Page 40: Dsp Unit (Ic-F70Dt/Ds Only)

    11-3 DSP UNIT (IC-F70DT/DS only) DSP UNIT L5 1µ 3.3V 3.3V 5.0V 3.3V IC13 XC6204B332M L2 1µ TC7S04F 5.0V 3.3V DVDD 3.3V DVDD 3.3V R88 47 VOUT 2SC4081 IC14 IC17 S-80928CNMC HN58X2416TI 1.5V R1230D151F R86 680 NLFV25T-330K-PF ERJ3GE-JPW CVDD 1.5V CVDD 1.5V...
  • Page 41 E-mail : info@icomcanada.com Unit 9, Sea St., Herne Bay, Kent, CT6 8LD, U.K. Phone : +44 (01227) 741741 Fax : +44 (01227) 741742 Icom (Australia) Pty. Ltd. : http://www.icomuk.co.uk E-mail : info@icomuk.co.uk A.B.N. 88 006 092 575 290-294 Albert Street, Brunswick, Victoria, 3056, Australia Icom France S.a...
  • Page 42 S-14124HZ-C1 © 2005 Icom Inc.

This manual is also suitable for:

Ic-f70dsIc-f70tIc-f70s

Table of Contents