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Icom IC-M502 Service Manual

Manual is about: VHF MARINE TRANSCEIVER

Summary of IC-M502

  • Page 1

    Vhf marine transceiver im502 service manual.

  • Page 2

    Introduction this service manual describes the latest service information for the ic-m502 vhf marine transceiver at the time of publication danger never connect the transceiver to an ac outlet or to a dc power supply that uses more than 16 v. This will ruin the transceiver. Do not expose the transce...

  • Page 3

    Table of contents section 1 specifications section 2 inside views 2 - 1 ic-m502 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 1 2 - 2 hm-127 (optional unit) . . . . . . . . . . . . . . . . . . . . . . ....

  • Page 4: Section 1

    1 - 1 section 1 specifications ‘ ‘ general • frequency coverage : 156.025–157.425 mhz (tx) 156.050–163.275 mhz (rx) • mode : 16k0g3e (fm) 16k0g2e (dsc) • usable channels : all international and usa channels • power supply requirement : 13.8 v dc (negative ground) • usable temperature range : –20˚c t...

  • Page 5

    1 - 2 * 1 low power only, * 2 receive only note: simplex channels 3, 21, 23, 61, 64, 81, 82 and 83 cannot be lawfully used by the general public in usa waters. Can 21a 22a 23 24 25 26 27 28 60 61a 62a 64 64a 65a 66a* 1 67 68 69 70* 2 71 72 can 73 74 77* 1 78a 79a 80a 81a 82a 83 83a 84 85 86 87 88 ca...

  • Page 6: Section 2

    Section 2 inside views 2 - 1 2-1 ic-m502 af power amplifier (ic14: la4425a) fm if ic (ic1: ta31136fn) 2nd if filter (fi3: alfy450e) main mpu (ic16: mb90f583bpfv-g) pll ic (ic2: µpd3140gs) vco circuit drive amplifier (q12: 2sc2954) 1st mixer* (q3: 3sk166) reset ic (ic15: s-80928anmp) * located under ...

  • Page 7

    2 - 2 2-2 hm-127 (optional unit) lcd (ds1: a0119) • bottom view cpu (ic1: µpd789405agk-a30-9eu) data buffer circuit system clock (x1: cstcc4.91mg) 8v regulator (ic6: ta7808f) dimmer circuit reset ic (ic7: s-80928anmp) mic amplifier (ic4: njm2125f) 5v regulator (ic5: ta78l05f) volume ic (ic3: m62429f...

  • Page 8: Section 3

    Section 3 disassembly instruction 3 - 1 caution: disconnect the dc power cable from the transceiver before performing any work on the trans- ceiver. Otherwise, there is danger of electric shock and/or equipment damage. A b • removing the logic unit q unsolder 2 point c. W disconnect microphone conne...

  • Page 9: Section 4

    Section 4 circuit description 4 - 1 4-1 receiver circuits 4-1-1 antenna switching circuit 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. Received signals...

  • Page 10

    4 - 2 4-1-5 af amplifier circuit the af amplifier circuit amplifies the detected signals to drive a speaker. The af circuit includes an af mute circuit for the squelch. Af signals from ic1 (pin 9) are passed through the analog switch (ic12, pins 10, 11), and are applied to the de-empha- sis circuit ...

  • Page 11

    4 - 3 4-3 pll circuits 4-3-1 general the pll circuit provides stable oscillation of the transmit fre- quency and receive 1st lo frequency. The pll circuit com- pares the phase of the divided vco frequency to the refer- ence frequency. The pll output frequency is controlled by a crystal oscillator an...

  • Page 12

    4 - 4 4-4 dsc circuits (dsc unit) 4-4-1 dsc encode circuit the dsc signal created at cpu (ic16), is passed through the buffer amplifier (q33) and applied to the analog switch (ic12, pin 1). The analog switch (ic12) is a modulation switch that switches between microphone audio signal and dsc signal. ...

  • Page 13

    4 - 5 4-7-2 main cpu (main unit; ic16) output port for the cloning data to the buffer (main unit; q37). Outputs clock signal for eeprom (ic17). Outputs serial data signal for eep- rom (ic17). Outputs select signal to the analog switch (ic12) for the microphone audio signal or dsc signal. D/a output ...

  • Page 14

    5 - 1 section 5 adjustment procedures 5-1 preparation ■ required test equipment equipment dc power supply rf power meter (terminated type) frequency counter fm deviation meter dc voltmeter grade and range output voltage : 13.8 v dc current capacity : 10 a or more measuring range : 1–50 w frequency r...

  • Page 15

    5 - 2 5-2 pll adjustments lock voltage reference frequency adjustment adjustment adjustment condition measurement value point unit location unit adjust 1 2 3 4 1 • operating channel : ch16 • receiving • operating channel : ch116 • receiving • operating channel : ch16 • output power : low • transmitt...

  • Page 16

    5-3 transmitter adjustments 5 - 3 output power frequency deviation adjustment adjustment adjustment condition measurement value point unit location unit adjust 1 1 • operating channel : ch16 • output power : high • transmitting • operating channel : ch16 • output power : low • connect an audio gener...

  • Page 17

    5 - 4 *this output level of a standard signal generator (ssg) is indicated as ssg’s open circuit. 5-4 receiver adjustments sensitivity squelch adjustment adjustment adjustment condition measurement value point unit location unit adjust 1 1 • operating channel : ch16 • [squelch] control : max. Counte...

  • Page 18: Section 6 Parts List

    6 - 1 section 6 parts list 6-1 ic-m502 [logic unit] [logic unit] s.=surface mount ic1 1140009280 s.Ic µpd78f9418agk-9eu ic2 1140008960 s.Ic hd66712sa03fs q1 1560000810 s.Fet 2sk1069-4-tl q2 1530002850 s.Transistor 2sc4116-bl (te85r) q3 1520000460 s.Transistor 2sb1132 t100 r q4 1560000810 s.Fet 2sk10...

  • Page 19

    [main unit] [vol unit] s.=surface mount r1 7210003080 variable tp96n97-15f-10ka-2345 j1 6510009470 connector s3b-zr w1 8900009860 cable opc-970 ep1 0910053363 pcb b 5428c r1 7210002360 variable tp96n97-15f-10kb-1301 w1 8900009870 cable opc-971 ep1 0910053372 pcb b 5429b s1 2250000220 encoder tp90n93...

  • Page 20

    [main unit] [main unit] s.=surface mount d16 1710001080 diode xb15a308 d17 1710001080 diode xb15a308 d18 1750000550 s.Diode 1ss355 te-17 d19 1790000700 diode dsa3a1 d20 1750000130 s.Diode da204u t107 d21 1750000130 s.Diode da204u t107 d22 1750000130 s.Diode da204u t107 d23 1750000550 s.Diode 1ss355 ...

  • Page 21

    [main unit] [main unit] s.=surface mount r119 7030003550 s.Resistor erj3geyj 822 v (8.2 k Ω) r120 7030003770 s.Resistor erj3geyj 564 v (560 k Ω) r121 7030003710 s.Resistor erj3geyj 184 v (180 k Ω) r122 7030003490 s.Resistor erj3geyj 272 v (2.7 k Ω) r123 7030003380 s.Resistor erj3geyj 331 v (330 Ω) r...

  • Page 22

    [main unit] [main unit] s.=surface mount c1 4030009510 s.Ceramic c1608 ch 1h 010b-t-a c2 4030007010 s.Ceramic c1608 ch 1h 100d-t-a c3 4030009570 s.Ceramic c1608 ch 1h 0r3b-t-a c4 4030007030 s.Ceramic c1608 ch 1h 150j-t-a c5 4030009520 s.Ceramic c1608 ch 1h 020b-t-a c6 4030006860 s.Ceramic c1608 jb 1...

  • Page 23

    [main unit] [main unit] s.=surface mount c206 4030007090 s.Ceramic c1608 ch 1h 470j-t-a c207 4030006860 s.Ceramic c1608 jb 1h 102k-t-a c208 4030006850 s.Ceramic c1608 jb 1h 471k-t-a c209 4030006900 s.Ceramic c1608 jb 1e 103k-t-a c210 4030006850 s.Ceramic c1608 jb 1h 471k-t-a c212 4030011810 s.Cerami...

  • Page 24

    S.=surface mount 6 - 7 6-3 hm-127 [main unit] ic1 1140009280 s.Ic µpd78f9418agk-9eu ic2 1110001810 s.Ic ta7368f (tp1) ic3 1110004490 s.Ic m62429fp 700c ic4 1120002830 s.Ic njm2125f-te1 ic5 1180000420 s.Ic ta78l05f (te12r) ic6 1180001250 s.Ic ta7808f (te16l) ic7 1110004710 s.Ic s-80928anmp-ddr-t2 ic8...

  • Page 25

    6 - 8 [main unit] [main unit] s.=surface mount r54 7030003440 s.Resistor erj3geyj 102 v (1 k Ω) r55 7030003640 s.Resistor erj3geyj 473 v (47 k Ω) r56 7030003440 s.Resistor erj3geyj 102 v (1 k Ω) r57 7030003520 s.Resistor erj3geyj 472 v (4.7 k Ω) r58 7030003280 s.Resistor erj3geyj 470 v (47 Ω) r59 70...

  • Page 26: Section 7

    7 - 1 j2 6510004880 antenna connector mr-ds-e 01 1 w1 8900009720 cable opc-943 1 ep1 6950000420 cover ltd-4/8-ic 1 mp1 8210017191 2345 front panel-1 assembly [black] 1 8210017172 2345 front panel (a)-1 assembly [white] 1 mp2 8210017150 2345 rear panel assembly [black] 1 8210017160 2345 rear panel (a...

  • Page 27

    7 - 2 mp5 (ch) mp6 (ch) mp2 (ch) mp1 (m) mp38 (ch) mp41 (ch) mp29 (ch) mp40 (ch) mp22 (ch) mp35 (ch) mp3 (ch) mp33 (ch) mp30 (ch) mp34 (ch) mp31 (ch) mp12 (ch) mp27 (ch) j2 (ch) ctrl unit sql unit main unit pwr-cord unit mp43 (ch) w1 (ch) j1 (ct) mp2 (l) ds1 (l) mp3 (l) ep1 (l) mp1 (l) s1 (l) mp36 (...

  • Page 28

    7 - 3 7-2 hm-126 w1 8900009770 cable opc-948 [black] 1 8900009780 cable opc-949 [white] 1 mp1 8210016861 2352 front panel-1 [black] 1 8210016961 2352 front panel (a)-1 [white] 1 mp2 8210016850 2352 rear panel [black] 1 8210017110 2352 rear panel (a) [white] 1 mp3 8930052160 2352 key 1 mp4 8930052150...

  • Page 29

    8 - 1 section 8 semi-conductor information • transistors and fet’s 2sa1576a t106r 2sb1132 t100 r 2sb1143 s 2sc2714-y 2sc2954 t2b 2sc3326 b 2sc3775-3-tb 2sc4081 t107 r 2sc4116 bl 2sc4215 o 2sj144 y 2sk210 gr 2sk880 y 2sk1069-4-tl 3sk166a-2-t7 3sk292 dta144eua t106 dtb123ek dtc144 tu t107 dtc144eua t1...

  • Page 30

    9 - 1 9-1 vol unit section 9 board layouts 1 to main unit w1 3 j1 vol1 vol2 gnd 9-2 dial unit 1 4 j2 dialb gnd nc diala to logic unit j3 9-3 sql unit 1 to logic unit j3 3 j1 sqlg sqlv sql5v.

  • Page 31

    9 - 2 • top view 9-4 logic unit.

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    9 - 3 • bottom view 1 39 38 64 65 1 20 21 40 41 61 80 60 102 103 128 keym gnd 1 to hm-126 j2 2 j1 sp+ sp+ +5v sreset vpp lmda hv sp– sp– gnd gnd 8v mlda hvs 1 13 14 2 to main unit j4 j4 dialb gnd diala sqlg sqlv +5v to sql and dial units 1 6 j3.

  • Page 33

    9 - 4 • top view r304 1 25 26 50 1 1 1 1 4 4 4 8 8 8 5 5 5 7 14 8 51 75 76 100 1 8 16 9 1 1 10 20 11 4 8 5 for flash 1 2 9 10 j1 gnd tmode tres sot0 gnd +5v taux3 p01 sin0 sck0 1 9 2 to optional unit ut-98 or ut-112 10 j6 +5v gnd optin scon gnd gnd gnd sck sdata opstb mici deti mico deto w1 to vol u...

  • Page 34

    9 - 5 • bottom view 1 1 1 1 7 14 8 8 4 5 7 14 8 4 8 5.

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    9 - 6 9-6 ctrl unit 9-9 hm-127 (optional unit) • top view 4 5 1 8 1 13 to main unit j3 14 2 j2 gnd dmda cmda gnd dscmod gnd micg pwr/icf3 mdda mcda +5v vcc safo smic 9-7 pwr-cord unit • top view 1 4 to main unit j1 hv hv gnd gnd 9-8 hm-126 • top view gnd spmic mice mic ptt kgnd keym 1 7 j1 • top vie...

  • Page 36

    9 - 7 • bottom view (hm-127) 1 40 41 60 61 8 5 4 1 5 1 10 6 4 1 8 5 80 1 20 21 4 5 8 rrxda pwrc rtxda pttc gnd micg af/mic vcc 1 8 to ic-m502 ctrl unit j1 j1 • bottom view (ctrl) • bottom view (hm-126) • bottom view (pwr-cord).

  • Page 37

    10 - 1 section 10 block diagram ant q31 dtc144eu q32 2sc4116 attb atta ic1 ta31136fn fi3 alfy450e ext.Sp option external speaker logic unit speaker mic hm-126 sp mic sp wx alert dsc dec sql ic4b njm4558m ic4a njm4558m ic20 njm2125f ic5 njm2211m ic6 tc7w14fu dsc decoder rf mute amp fm det 2nd mix 2nd...

  • Page 38

    11 - 1 section 11 voltage diagram 11-1 logic unit ds2 sml-311yt scan dsc dtrs distress ds11 ds9 ds7 ds12 ds10 ds8 ds16 ds15 ds1 tsd0393 r53 220 ds14 power sw h/l dsc r42 220 r43 220 +5v ds13 s1 spph22014a ds6 ds17 ic scan ch/wx 16 r41 220 ds4 ds3 ds5 d1 ma8043 r38 220 ic chwx ch16 c12 0.001 c11 10 c...

  • Page 39

    11 - 2 11-2 main unit 1 2 3 4 5 6 7 8 9 10 11 12 13 14 j2 pwrc/icf3 gnd mdda dmda mcda j1 1 tc4w53f ic1 2 3 4 8 7 6 5 d5v smic safo pttc 1 c11 1 c12 c13 1 gnd 5 7 4 3 1 8 2 6 vcc af/mic micg extrxd pwrc/icf3 exttxd pttc +5v vcc vcc dscmod dscmod safo gnd smic micg cmda reset r19 10 c31 47p c32 0.022...

  • Page 40

    11 - 3 gnd vol1 vol2 r1 tp96n97-15f- 10ka-2345 gnd 1 2 3 j1 to logic w2 chassis j2 c1 18p w2 c7 0.001 c9 0.001 l2 ls-440 r3 33k r5 10k r8 470 r287 1 r7 100 r277 r1 d31 39 ma77 c10 0.001 c21 0.5p w5 w6 cp5 c26 0.01 c27 0.001 c22 2p r263 10k c307 0.22 1 3 2 4 5 ic20 njm2125f c308 0.1 r266 1k r267 10k ...

  • Page 41

    11 - 4 11-3 hm-127 (optional unit) j2 6 5 4 3 2 1 gnd rxd txd reset vpp 5v stxd srxd reset vpp 5v 5v srxd stxd 47k r55 1k r54 tc7w14fu ic8 8 7 6 5 4 3 2 1 2sa1576 q11 47 r58 4.7k r57 rrxda ptt 0.1 c46 2sc4081 q10 rtxda 27k r51 1k r56 5v 0.01 c45 0.027 c42 2sk1069 q9 s-80928anmp ic7 5 cd 4 nc 3 vss 2...

  • Page 42

    11 - 5 11-4 hm-126 1 2 p2 to logic unit j1 (ic-m501euro) to main unit j7 (ic-m501euro) keym kgnd green brown red black white green brown w1 (chassis) in out ptt gnd mic spmic keym mice 1 2 3 4 5 6 7 j1 kgnd 1 2 3 4 5 6 7 p3 ptt mic mice spmic keym up-on 2.0v dn-on 3.0v h/l-on 3.8v gnd kgnd w1 w4 w3 ...

  • Page 43

    Communication equipment himmelgeister str. 100, d-40225 düsseldorf, germany phone : 0211 346047 fax : 0211 333639 url : http://www.Icomeurope.Com unit 9, sea st., herne bay, kent, ct6 8ld, u.K. Phone : 01227 741741 fax : 01227 741742 url : http://www.Icomuk.Co.Uk zac de la plaine, rue brindejonc des...

  • Page 44

    1-1-32, kamiminami, hirano-ku osaka 547-0003, japan s-13710hz-cd © 2000 icom inc..