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Icom IC-M304 Service Manual

Other manuals for IC-M304: Instruction Manual, Instruction Manual
Manual is about: Icom America Inc. VHF Marine Transceiver Instruction Manual

Summary of IC-M304

  • Page 1

    S-14311xz-c1 dec. 2006 vhf marine transceiver ic-m304.

  • Page 2

    This service manual describes the latest service information for the ic-m304 vhf marine transceiver at the time of publication. Never connect the transceiver to an ac outlet or to a dc power supply that uses more than 15 v. This will ruin the transceiver. Do not reverse the polarities of the power s...

  • Page 3

    Contents section 1 specifications section 2 inside views section 3 disassembly instructions section 4 circuit descripiton 4-1 receiver circuits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 4-2 transmitter circuits . . . . . . . . ...

  • Page 4: Section 1

    1 - 1 section 1 specifications m general • frequency coverage : tx rx 156.025–157.425 mhz 156.050–163.275 mhz • type of emission : 16k0g3e (fm), 16k0g2b (dsc) • channel spacing : 25 khz • antenna impedance : 50 Ω (nominal) • operating temperature range : –20˚c to +60˚c; –4˚f to +140˚f • power supply...

  • Page 5

    1 - 2 : e t o n 3 8 d n a 2 8 , 1 8 , 4 6 , 1 6 , 3 2 , 1 2 , 3 , s l e n n a h c x e l p m i s t o n n a c . S r e t a w . A . S . U n i c il b u p l a r e n e g e h t y b d e s u y ll u f w a l e b * 1 . Y l n o r e w o p w o l * 2 . R e w o p h g i h y r a t n e m o m * 3 . Y l n o n o i t a r e ...

  • Page 6: Section 2

    2 - 1 section 2 inside views • main unit • logic unit tx power module (ic4: s-av35a) 2nd if filter (fi3: lt450ew) dsc decoder (ic3: njm2211m) idc/lpf (ic10: njm4558m) mic mute switch (ic7: tc7w66eu) 1st if filters (fi1: fl-368, fi2: fl-399a) if ic (ic1: ta31136fn) pll ic (ic8: upd3140gs) vco dimmer ...

  • Page 7: Section 3

    3 - 1 section 3 disassembly instruction 1. Removing the front panel q unscrew 8 screws a, as shown below, and then remove the case in the direction of the arrow. 2. Removing the main unit q unsolder the external speaker cable f (2 points), and dc cable g (2 points), on the bottom side of the main un...

  • Page 8: Section 4

    4 - 1 section 4 circuit description 4-1 receiver circuits 4-1-1 antenna switching circuit (main unit) the antenna switching circuit functions as a low-pass filter while receiving and as resonator circuit while transmitting. The circuit does not allow transmit signals to enter receiver circuits. Rece...

  • Page 9

    4 - 2 4-2 transmitter circuits 4-2-1 microphone amplifier circuit (main unit) the microphone amplifier circuit amplifies audio signals with +6 db/octave pre-emphasis from the microphone to a level needed at the modulation circuit. The af signals from the microphone are amplified at the microphone am...

  • Page 10

    4 - 3 4-3 pll circuits 4-3-1 general (main unit) the pll circuit provides stable oscillation of the transmit frequency and receive 1st lo frequency. The pll circuit compares the phase of the divided vco frequency to the reference frequency. The pll output frequency is controlled by a crystal oscilla...

  • Page 11

    4 - 4 4-4 dsc circuits 4-4-1 dsc encode circuit (logic unit and main unit) the dsc signal is created at the cpu (ic1, pin 9). The signal passes through the buffer amplifier (ic6a, pins 1, 3), and is then applied to the d/a convertor (r176–r179) to convert into the analog signal. The analog signal pa...

  • Page 12

    4 - 5 4-7 cpu port allocations pin no. Port name description 2 keym input port for keys on hm-150b/sw. Approx. 2.02 v: [ y] key is pushed. Approx. 3.00 v: [ z] key is pushed. Approx. 3.84 v: [h/l] key is pushed. 3 txdet input port for transmit detected voltage. 4 lbat input port for low battery dete...

  • Page 13: Section 5

    5 - 1 section 5 adjustment procedure ¤ required test equipments equipment grade and range equipment grade and range dc power supply output voltage : 13.8 v dc current capacity : more than 10 a dc voltmeter input impedance : 50 k Ω /v dc or more rf power meter (terminated type) measuring range : 0.1–...

  • Page 14

    5 - 2 5-2 frequency adjustment adjustment adjustment condition operation value lock voltage (verify) 1 • channel : ch16 (156.800 mhz) • receiving connect a dc voltmeter to the check point ‘lv.’ 1.3–2.3 v (verify) 2 • channel : ch16 (156.800 mhz) • output power : low • connect a power meter to the an...

  • Page 15

    5 - 3 5-3 transmit adjustment adjustment adjustment condition operation value transmit output power 1 • channel : ch16 (156.800 mhz) • output power : high • connect an rf power meter to the ant- enna connector. • transmitting adjust r135 (pwr). 23.5 w deviation 1 • channel : ch16 (156.800 mhz) • out...

  • Page 16

    5 - 4 5-4 receive adjustment adjustment adjustment condition connection value receive sensitivity 1 • channel : ch16 (156.800 mhz) • [squelch] : open (max. Counterclockwise) • connect an external speaker to the [ext sp] lead receptacle. • connect an ssg to the antenna connector and set as; frequency...

  • Page 17: Section 6

    6 - 1 section 6 parts list m.=mounted side (t: mounted on the top side, b: mounted on the bottom side) [logic unit] ref order description m. H/v no. No. Location ic1 1140013950 s.Ic m37560mfa-347gp b 53/33 ic2 1170000352 s.Ic pc357n6j000f b 13.4/19.7 ic3 1130007431 s.Ic tc7s14fu (te85r,f) b 13.7/25....

  • Page 18

    6 - 2 m.=mounted side (t: mounted on the top side, b: mounted on the bottom side) [main unit] ref order description m. H/v no. No. Location l3 6110001600 col la-243 l6 6150003821 col ls-440-lf l7 6150003821 col ls-440-lf l8 6150003821 col ls-440-lf l9 6150003821 col ls-440-lf l10 6200010090 s.Col el...

  • Page 19

    6 - 3 m.=mounted side (t: mounted on the top side, b: mounted on the bottom side) [main unit] ref order description m. H/v no. No. Location c36 4030006860 s.Cer c1608 jb 1h 102k-t t 100.3/38.7 c42 4030009350 s.Cer c1608 ch 1h 3r5b-t t 91.6/26.5 c44 4030006860 s.Cer c1608 jb 1h 102k-t t 92.1/32.1 c46...

  • Page 20: Section 7

    Screw abbreviations a, b0, bt: self-tapping ph: pan head zk: black ni-zu: nickel-zinc sus: stainless 7 - 1 section 7 mechanical parts and disassembly [chassis parts] ref order description qty. No. No. J1 6510004880 mr-dse-01 1 w1 8900012331 opc-1258a 1 mp2 8010019302 2685 chassis-2 1 mp3 8930061050 ...

  • Page 21

    7 - 2 mp2(c) mp2(c) mp5(c) mp14(c) mp7(c) w1(c) w1(c) b f e j1(c) mp3(c) mp3(c) mp16(c) mp16(c) mp4(c) mp16(c) mp16(c) mp16(c) mp11(c) mp6(c) mp4(f) r1(vr) r1(sql) mp1(f) mp11(f) w2(f) d d mc1(f) mc1(f) mp11(f) mp12( f) mp12(f) mp13(c) mp10(c) mp19(c) mp12(c) mp12(c) mp12(c) mp8(c) main unit unit ab...

  • Page 22

    8 - 1 section 8 semiconductor information • dtc114tua (marking: 04) • kta1664y (marking: qo) • 2sc4215 (marking: xx) • 2sc4226 (marking: r24) • 3sk131 (marking: v13) • fmw1 (marking: w1) • krc402 (marking: nb) • krc404 (marking: nd) • kta2015y (marking: z) • ktc4080 (marking: q) • transisters and fe...

  • Page 23: Section 9

    9 - 1 section 9 board layouts ds2 3 s d 4 s d ds5 ds6 ds7 6 1 t s i d c s d h c n a c s 1 s d 0 h 5 h 0 1 h 5 1 h 0 2 h 5 2 h 0 3 h 5 3 h 0 4 h 5 4 h 0 5 h 5 5 h 0 6 h 5 6 h 0 7 h 5 7 h 0 8 h v0 v5 v10 v15 v20 v25 v30 v35 v40 v45 v50 1 c s1 h0 h5 h10 h15 h20 h25 h30 h35 h40 h45 0 v 5 v 0 1 v 5 1 v 0...

  • Page 24

    9 - 2 c1 c2 3 c 4 c 5 c c6 7 c 1 1 c c12 3 1 c c14 c16 7 1 c c18 c21 2 2 c 3 2 c c25 6 2 c c31 c32 1 4 c 2 4 c 3 4 c 4 4 c d1 2 d d3 1 c i 2 c i ic3 4 c i ic5 ic6 1 j 2 j q2 q3 4 q 6 q 3 r 1 r 4 r 5 r 4 1 r 5 1 r 6 1 r 1 2 r 2 2 r 3 2 r 4 2 r 5 2 r 6 2 r r27 r28 r29 r30 1 3 r 5 3 r r36 7 3 r 8 3 r r...

  • Page 25: Section 10

    10 - 1 section 10 block diagram lpf r1 bpf cerami c buff x1:cr-834 7.9872mhz id c reset sp1 photo couple lcd eeprom af am p tx/rx sw apc ctrl 21.25mhz bp f xtal noise det tx mut e ctrl ci-v i/f ant if am p r184 rfout det rf am p 2nd lo buff fm det pwr ctrl ygr amp pw r amp lpf buff noise am p di m c...

  • Page 26: Section 11

    11 - 1 section 11 voltage diagram 3 . 3 1 v r : 6 . 8 5 v dim max:12.27v 0v 0 . 4 6 v 7.9872mhz ds 7 ry-sp110uhy24 27 r23 s-80942cnmc ic5 1 out 2 vdd 3 vss 4 nc 5 cd j2 b4b-zr-sm4-tf 1 2 3 4 5 6 12k r27 39k r24 470p c44 10k r3 dtrs s7 up s5 1m r65 10k r42 10k r62 47k r15 kds122 d3 5.6k r1 njm2 904m ...

  • Page 27

    11 - 2 c112 r:3.48v r:0.42v r:3.93v r:0.23v r:2.37v r:7.55v r:2.14v r:3.62v r:4.26v 4.29v 3.84v r:2.04v t:4.78v hi :2.87v low:1.43v r:2.78v 4.73v r:7.72v r:1.91v 470p c236 100p c67 0.001 c6 r148 1.8k 8.2k r95 470 r201 22p c138 r35 100k 10 c276 47 r188 6.8k r32 2sc4226 q13 r139 2.2k r140 10k cr-804a ...

  • Page 28: Section 12

    12 - 1 section 12 hm-164b/sw/g mp8(c) mp14(c) w1(c) mp2(c) mp17(c) mp16(c) mp19(c) mp4(c) mp5(c) mp20(c) mc1(m) mp3(c) mp12(c) mp7(c) mp1(c) main unit mp9(c) mp6(c) mp13(c)×5 mp15(c)×5 • chassis parts list ref order description qty. No. No. W1 8900012212 opc-1249b [black] 1 8900013570 opc-1406 [supe...

  • Page 29

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  • Page 30

    1-1-32, kamiminami, hirano-ku, osaka 547-0003, japan s-14311xz-c1 © 2006 icom inc..

  • Page 31

    • replacement unit information for ic-m304 front unit (incl. Logic, vr, sql units and hm-164) order no. Unit name 0329890101 0329890201 0329890301 u m304 #01 front (front+logic+vr+sql, and hm-164b) [black] u m304 #02 front (front+logic+vr+sql, and hm-164sw) [super white] u m304 #03 front (front+logi...