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Icom IC-446S Service Manual

Manual is about: PMR446 FM

Summary of IC-446S

  • Page 1

    Service manual 6-9-16, kamihigashi, hirano-ku, osaka, 547-0002, japan s-136007ii-cd © 1999 icom inc. Pmr446 fm transceiver cover 99.12.18 8:39 am page 1.

  • Page 2

    Introduction danger ordering parts repair notes 6-9-16, kamihigashi, hirano-ku, osaka 547-0002, japan phone : 06 6793 5302 fax : 06 6793 0013 communication equipment himmelgeister str. 100, d-40225 düsseldorf, germany phone : 0211 346047 fax : 0211 333639 url : http://www.Icomeurope.Com unit 9, sea ...

  • Page 3

    Table of contents section 1 specifications section 2 inside views section 3 disasembly instruction section 4 circuit description 4-1 receiver circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1 4-2 transmiter circuits . . . . . . . . ...

  • Page 4: Section 1

    All stated specifications are subject to change without notice or obligation. ‘ ‘ general number of channels : 8 ch type of emission : 8k50f3e frequency stability : ±2.5 khz frequency resolution : 12.5 khz power supply requirements : 3 × aa(r6) dry, alkaline; (negative ground) or optional bp-202 cur...

  • Page 5: Section 2

    Section 2 inside views • main unit 2 - 1 • rf unit t+3 current amplifier q27: 2sc4081 q28: 2sb798 q101: umz1n d5: 1ss355 r+3 current amplifier (q18: 2sa1586) af amplifier (ic9: njm2070m) eeprom (ic3: at24c02n) cpu (ic1: µ pd753036gk) +3 regurator (ic6: s-81230sg) top view bottom view 1st mixer (q2: ...

  • Page 6: Section 3

    Section 3 disasembly instruction 3 - 1 a b b main unit rf unit c d e g f • removing the rear panel 1 unscrew 1 screw a , and 4 screws b . 2 remove the rear panel in the direction of the arrow. • removing the rf unit 1 remove 1 knob c , and unscrew 1 nut d . 2 then remove the rf unit. • removing the ...

  • Page 7: Section 4

    4 - 1 section 4 circuit description 4-1 receiver circuits 4-1-1 antenna switching circuit (rf unit) received signals from the antenna connector are passed through the low-pass filter (l5, l6, c8–c12). The filtered sig- nals are applied to the λ ⁄ 4 type antenna switching circuit (d101, d102, l4, l20...

  • Page 8

    4 - 2 4-1-6 squelch circuit (rf and main units) • noise squelch the noise squelch circuit cuts out af signals when no rf signals are received. By detecting noise components in the af signals, the squelch circuit switches the af mute switch. A portion of the af signals from the fm if ic (rf unit; ic2...

  • Page 9

    4 - 3 4-4 power supply circuits voltage line 4-5 port allocations 4-5-1 cpu (main unit; ic1) line batt 3v +3v r+3 t+3 description the voltage from the connected battery cells. Common 3 v converted from the batt line at the 3v regulator circuit (ic6). The circuit outputs the voltage regardless of the...

  • Page 10

    5 - 2 section 5 adjustment procedures 5-1 preparation ■ required test equipment equipment dc power supply frequency counter fm deviation meter dc voltmeter rf power meter (terminated type) grade and range output voltage : 4.5 v dc current capacity : 1 a or more frequency range : 0.1–600 mhz frequenc...

  • Page 11

    5 - 3 reference frequency output power fm deviation 5-2 pll and transmitter adjustments adjustment adjustment adjustment condition measurement value point unit location unit adjust 466.00625 mhz 470 mw ±2.45 khz 10 mv ±3db 1 1 1 2 • operating channel : ch 01 • transmitting • operating channel : ch 0...

  • Page 12

    5 - 4 squelch 5-3 receiver adjustment adjustment adjustment condition measurement value adjustment unit location audio signal disappears. 1 2 • operating channel : ch 04 • connect an ssg to j1 on the rf unit and set as: frequency : 446.04375 mhz level : 0.14 µv* (–124 dbm) modulation : off • receivi...

  • Page 13: Section 6

    [main unit] [main unit] ic1 1140008770 s.Ic µpd753036gk-559-be9 ic2 1110002820 s.Ic njm2100m-t1 ic3 1140008350 s.Ic at24c02n-10si-2.7 ic5 1110004710 s.Ic s-80928anmp-ddr-t2 ic6 1180001150 s.Ic s-81230sg-qb-t1 ic9 1110002810 s.Ic njm2070m-t1 q1 1590000720 s.Transistor dta144eua t106 q2 1590001440 s.T...

  • Page 14

    Ic1 1130007610 s.Ic µpd3140gs-e1 (ds8) ic2 1110003200 s.Ic ta31136fn (el) q1 1530002600 s.Transistor 2sc4215-o (te85r) q2 1580000670 s.Fet 3sk284 (te85r) q3 1530002920 s.Transistor 2sc4226-t2 r25 q6 1530003320 s.Transistor 2sc5108-y (te85r) q7 1530003320 s.Transistor 2sc5108-y (te85r) q8 1530002940 ...

  • Page 15

    [rf unit] [rf unit] s.=surface mount r33 7030003550 s.Resistor erj3geyj 822 v (8.2 k Ω ) r34 7030003420 s.Resistor erj3geyj 681 v (680 Ω ) r35 7030003640 s.Resistor erj3geyj 473 v (47 k Ω ) r36 7030003360 s.Resistor erj3geyj 221 v (220 Ω ) r37 7030003600 s.Resistor erj3geyj 223 v (22 k Ω ) r45 70300...

  • Page 16: Section 7

    Section 7 mechanical parts and disassembly 7 - 1 screw abbreviations a, b0, bt: self-tapping ph: pan head fh: flat head bih: bind head ni: nickel sus: stainless zk: black sp1 2510000960 speaker k036na500-26 1 ep1 3310002110 antenna 2123 ant 1 mp1 8210015181 2045 front panel-1 [black] 1 8210016101 20...

  • Page 17

    7 - 2 unit abbreviation (c): chassis parts, (m): main unit, (rf): rf unit mp1 (c) sp1 (c) mp10 (c) mp12 (c) ep1 (m) ds2 (m) mp7 (c) mp5 (c) main unit mp20 (c) mp25 (c) mp4 (rf) mp14 (c) mp17 (c) mp2 (rf) mp16 (c) mp23 (c) mp5 (rf) mp11 (c) mp13 (c) mp4 (c) mp2 (c) mp15 (c) mp25 (c) mp9 (c) mp8 (c) r...

  • Page 18

    Section 8 semi-conductor information 8 - 1 • diodes • transistor and fet’s 2sa1362-gr (symbol: aeg) 2sc4213-b (symbol: ab) 2sc5108-y (symbol: mc) un9214 (symbol: 8a) dtc114eua t106 (symbol: 14) dta123jua t106 (symbol: 132) xrf9482t1 (symbol: 9482) umz1n tr (symbol: z1) umz2n tr (symbol: z2) 2sj144-y...

  • Page 19: Section 9

    Section 9 board layouts 9-1 main unit • top view 9 - 1 c20 c97 c96 r26 r89 c9 c42 r22 r27 c50 r24 r25 r55 r56 c49 c95 r61 c15 c75 c71 r90 c74 r49 r200 r201 r114 r115 r119 r204 w3 r98 c53 c60 c81 r74 r76 c63 r23 r80 r78 c88 w7 c90 c62 r102 r12 c35 c34 r10 c25 c3 r9 r31 r202 r118 r110 r45 r36 c36 c31 ...

  • Page 20

    9 - 2 r87 c72 c59 q23 ic9 j4 q5 ic3 q10 r58 r88 r86 c21 c47 r54 c44 r106 c82 j1 j3 s1 r112 c86 ic1 test b5420b x1 r68 r81 r72 c61 c46 r63 c45 r79 c87 r97 r99 c85 c99 r2 r30 c1 r39 c73 r40 r64 w2 r5 r53 c24 c98 c93 r52 r51 c83 q2 q12 q1 q29 r32 r35 c28 c91 c10 r14 c51 r62 r103 r101 r117 r105 r203 r10...

  • Page 21

    9 - 3 9-2 rf unit • top view c81 r58 c28 c89 c30 c44 c10 c12 l23 c8 l10 r66 r68 r71 c96 c3 l25 l203 q201 l1 l204 l5 l6 q2 q15 r60 j2 ic1 c62 c17 q202 c68 c82 d9 q14 q13 d8 c86 c48 c61 c69 r10 w5 l15 r45 c16 c26 c23 r27 r64 r302 r215 r205 d103 c206 r209 r202 c202 w202 l205 c207 c208 l201 w201 c201 c2...

  • Page 22

    9 - 4 • bottom view c42 r88 c43 c13 r37 c21 l21 r55 c74 r51 c78 c77 c73 c80 ic2 c35 r52 d1 q8 d2 c60 c88 c85 q3 fi1 c75 r53 r36 c55 c57 r35 l14 c64 r33 r50 r206 q12 c84 q7 c56 q6 c51 d4 d5 l13 l12 c32 r70 j1 fi3 fi2 b5421b r72 c6 l3 r7 r75 r76 q16 r74 c93 c92 c91 d102 d101 c210 c209 r207 c205 r301 l...

  • Page 23

    Section 10 block diagram 10 - 1 ds1 ln1371g ctcin d/a remin ptt2 micsw mmut rmut afon rxv txv power lcd ds2: ld-bu10503j volt sens reset ic5: s-80928anmp x2 cdbca450cx24 fi3:cfwm450g ceramic bpf fmdet s out if amp noise det ic2 ta31136fn q13: 2sc4081 q14: 2sa1586 d8 : 1ss355 d9 : 1ss355 q6: 2sc5108 ...

  • Page 24

    Section 11 voltage diagram 11 - 1 11-1 main unit lon: 0 lof: 3.02 lon: 0.76 lof: 0 c: 3.81 t: 3.05 r: 2.37 c: 3.02 c: 3.10 c: 1.44 t: 0 r: 0.88 c: 1.95 t: 0 r: 2.95 c: 3.12 t: 0 r: 3.02 c: 3.10 t: 1.58 r: 0 t: 3.05 r: 0 t: 1.51 r: 0 c: 0 c: 3.12 t: 1.53 r: 0 t: 1.50 r: 0 c: 2.46 c: 3.11 t,sc: 0 so: ...

  • Page 25

    11-2 rf unit 11 - 2 t: 0 r: 0.72 t: 0 r: 1.83 t: 0 r: 2.60 t: 0 r: 1.72 t: 0 r: 2.94 t: 0 r: 0.77 t: 0 r: 2.28 t: 0 r: 0.27 t: 0 r: 2.19 c: 2.82 t: 0 r: 0.97 t: 0 r: 1.84 t: 0 r: 1.85 c: 4.5 c: 3.02 c: 2.99 c: 3.06 c: 0.75 c: 0.70 t: 2.24 r: 0 t: 0.85 r: 0 t: 2.85 r: 0.01 c: 1.89 c: 1.22 t: 0 r: 0.7...

  • Page 26

    Introduction danger ordering parts repair notes 6-9-16, kamihigashi, hirano-ku, osaka 547-0002, japan phone : 06 6793 5302 fax : 06 6793 0013 communication equipment himmelgeister str. 100, d-40225 düsseldorf, germany phone : 0211 346047 fax : 0211 333639 url : http://www.Icomeurope.Com unit 9, sea ...

  • Page 27: Service

    Service manual 6-9-16, kamihigashi, hirano-ku, osaka, 547-0002, japan s-136007ii-cd © 1999 icom inc. Pmr446 fm transceiver cover 99.12.18 8:39 am page 1.