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Icom IC-A23 Service Manual

Other manuals for IC-A23: Instruction Manual, Instruction Manual
Manual is about: VHF AIR BAND TRANSCEIVER

Summary of IC-A23

  • Page 1

    13706mz-cd ' 2000 icom inc. 6-9-16, kamihigashi, hirano-ku, osaka 547-0002, japan count on us! Ic-a5 air band fm transceiver ic-a23 ic-a23 ic-a5.

  • Page 2

    Introduction this service manual describes the latest service information for the ic-a23/ic-a5 fm 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. Such a connection could cause a fire hazard and/or electric...

  • Page 3

    Section 1 specifications section 2 inside views section 3 disassembly instructions section 4 circuit description 4 – 1 receiver circuits ................................................................................................................... 4 – 1 4 – 2 transmitter circuits .................

  • Page 4: Section 1

    1 - 1 section 1 specifications ‘ ‘ general • frequency coverage : tx 118.000–136.975 mhz rx 108.000–136.975 mhz * 1 wx 161.650–163.275 mhz * 1 * 1 : ic-a23 only, ic-a5; 118.000–136.975 mhz * 2 : u.S.A version only • type of emission : 6k00a3e, 16k0g3e (weather channel; [usa] version only) • channel ...

  • Page 5: Section 2

    Clock oscillator (x1: cr-534, 5.039 mhz) eeprom (ic7: hn58x2432) reset (ic2: s-80945almp) ptt detector (q10: 2sb1462) microphone mute (q12: un9211) cpu (ic1: m38267m6l) vor circuit (ic-a23 only) microphone amplifier (ic9: ba3308f) af amplifier (ic6: ta7368f) ygr amplifier (q3: 2sk2973) vco circuit r...

  • Page 6: Section 3

    3 - 1 section 3 disassembly instructions 1 removing the chassis panel q remove 1 knob, b , and unscrew 1 nut, a . W unscrew 2 screws c (2 × 10 mm, black). E remove the chassis panel in the direction of the arrow. 2 removing the logic unit q remove the sealing rubber. W unsolder 1 point, d , to separ...

  • Page 7: Section 4

    4 - 1 section 4 circuit description 4-1 receiver circuits 4-1-1 antenna switching circuit (rf unit) the antenna switching circuit functions as a low-pass filter while receiving. However, its impedance becomes very high while d8 and d9 are turned on. Thus transmit signals are blocked from entering th...

  • Page 8

    4 - 2 4-1-5 af circuit (rf unit) the af amplifier circuit amplifies the demodulated af sig- nals to drive a speaker. Af signals from the am detector (q18; while in am mode) or if ic (ic1, pin 9; while in fm mode) are applied to the am/fm switch (ic2, pin 6 or 7). The output signals from pin 1 are ap...

  • Page 9

    4 - 3 4-1-8 anl circuit (rf unit) the anl (automatic noise limiter) circuit (q21, d18) reduces pulse noises. The am detector output signal from the q18 is applied to the cathode of d18 passing through r99 where it is divided by r99 and r100. The signal is also applied to the anode of d18, passing th...

  • Page 10

    4-2 transmitter circuits 4-2-1 microphone amplifier circuit (logic and rf units) the microphone amplifier circuit amplifies audio signals with +6 db/octave pre-emphasis characteristics from the micro- phone to a level needed for the modulation circuit. Af signal from the internal/external microphone...

  • Page 11

    4 - 5 4-3 pll circuit (rf unit) a pll circuit provides stable oscillation of the transmit fre- quency and receive 1st lo frequency. The pll output com- pares the phase of the divided vco frequency to the refer- ence frequency. The pll output frequency is controlled by the divided ratio (n-data) of a...

  • Page 12

    4 - 6 pin number 5 7 11 12 13 14 port name detmite r5c wxc anlc embi afc description outputs detector mute signal to the am/fm select switch (ic2, pin 2). Outputs receiver 5v control signal to the rx controller (q20). Outputs am/fm (wx ch) select signal to the rx shift circuit (q34, d25) and am/fm s...

  • Page 13

    5-1 preparation most of adjustments must be adjusted on the adjustment mode after programmed adjustment frequency data into the transceiv- er’s memory channel. When program adjustment frequency data into memory channels, the optional cs-a23 cloning software (rev. 1.0 or later) and opc-478 cloning ca...

  • Page 14

    5 - 2 file edit view toolbar mr bank0 bank1 bank2 bank3 bank4 bank5 bank6 bank7 bank8 bank9 wx (wx version only) com port clone help ch 00 01 118.500 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 wx channel rx/(tx) frequency tx frequency dup name tx inhibit mem untitled cs-a23 common setting ? ...

  • Page 15

    5 - 3 5-2 pll and transmitter adjustments • the “pll lock voltage” adjustment must be performed at the “normal” mode. • “reference frequency”, “idling current”, “output power” and ‘am modulation” adjustments must be per- formed at the “adjustment” mode. Am modulation adjustment r41 pll lock voltage ...

  • Page 16

    5 - 4 5-3 receiver adjustment • the follow adjustment must be performed at the “adjustment” mode, and turn [dial] to start each adjustment and finish automatically. Receiver sensitivity sqelch level vor phase (ic-a23 only) vor off (ic-a23 only) 1 2 1 2 1 1 • operating channel : 3 ch [bf1adj] (108.20...

  • Page 17: Section 6  Parts List

    6 - 1 s.=surface mount ic1 1140009230 s.Ic m38267m8l-266gp ic2 1110004750 s.Ic s-80945almp-da9-t2 ic3 1180000800 s.Ic s-81350hg-kd-t1 ic7 1130009680 s.Ic hn58x2432ti ic8 1130007510 s.Ic bu4094bcfv-e1 ic9 1110003670 s.Ic ba3308f-t1 ic11 1110003790 s.Ic njm2903v-te1 [a23] only ic12 1110003780 s.Ic njm...

  • Page 18

    6 - 2 s.=surface mount r84 7030003520 s.Resistor erj3geyj 472 v (4.7 k Ω ) [a23] only r85 7030003590 s.Resistor erj3geyj 183 v (18 k Ω ) [a23] only r86 7030003520 s.Resistor erj3geyj 472 v (4.7 k Ω ) [a23] only r87 7510000980 s.Thermistor tbps1r333k460h5q [a23] only r88 7030003620 s.Resistor erj3gey...

  • Page 19

    6 - 3 s.=surface mount ic1 1110003490 s.Ic ta31136fn (d,el) ic2 1130006220 s.Ic tc4w53fu (te12l) ic3 1130008830 s.Ic tb31207afn (el) ic4 1110003690 s.Ic m62354gp 75ec ic5 1130007570 s.Ic bu4094bcfv-e2 ic6 1110001810 s.Ic ta7368f (tp1) ic13 1110002400 s.Ic njm2107f-te1 ic14 1110002400 s.Ic njm2107f-t...

  • Page 20

    6 - 4 s.=surface mount r43 7030003720 s.Resistor erj3geyj 224 v (220 k Ω ) r44 7030003700 s.Resistor erj3geyj 154 v (150 k Ω ) r45 7030003640 s.Resistor erj3geyj 473 v (47 k Ω ) r46 7030003700 s.Resistor erj3geyj 154 v (150 k Ω ) r47 7030003680 s.Resistor erj3geyj 104 v (100 k Ω ) r48 7030003770 s.R...

  • Page 21

    [rf unit] [rf unit] s.=surface mount c44 4030006860 s.Ceramic c1608 jb 1h 102k-t-a c45 4030006860 s.Ceramic c1608 jb 1h 102k-t-a c46 4030006860 s.Ceramic c1608 jb 1h 102k-t-a c47 4030006860 s.Ceramic c1608 jb 1h 102k-t-a c48 4030006860 s.Ceramic c1608 jb 1h 102k-t-a c49 4550002980 s.Tantalum temsva ...

  • Page 22

    [rf unit] s.=surface mount c597 4030006900 s.Ceramic c1608 jb 1e 103k-t-a c598 4030006850 s.Ceramic c1608 jb 1h 471k-t-a c599 4030006850 s.Ceramic c1608 jb 1h 471k-t-a j1 6450000870 connector hec2711-01-020 j2 6450002150 connector hsj1594-010010 j3 6510019870 s.Connector axk5s40045p j4 6510021900 s....

  • Page 23: Section 7

    J1 6510022390 ant connector bnc-r159 1 s1 7600000210 encoder tp70n00e20-15f-1903 1 sp1 2510000840 speaker cs028014-12 1 mp1 8210016991 1903 front panel(c)-1 assembly [ic-a23] 1 8210017131 1903 front panel(c)-1 assembly [ic-a5] 1 mp2 8010017151 1903 chassis-1 1 mp3 8930052580 2378 main seal 1 mp4 893...

  • Page 24

    7 - 2 mc1 (l) mp15 (c) mp22 (c) mp5 (c) mp19 (c) mp9 (c) ds1 (l) ep2 (l) mp1 (l) mp3 (l) mp3 (c) s1 (c) mp1 (r) mp12 (c) mp2 (c) mp6 (c) mp21 (c) mp21 (c) mp5 (l) mp4 (l) mp3 (r) mp7 (r) mp4 (r) mp9 (r) mp8 (r) mp6 (r) mp5 (r) j1 (c) mp2 (l) mp20 (c) mp16 (c) mp17 (c) mp28 (c) mp21 (c) mp11 (c) mp27...

  • Page 25

    Name symbol inside view b1 e b2 c1 c2 xp1501-ab 5r e1 c2 b1 c1 e2 b2 xp4315 cb section parts list section 8 semi-conductor information 8 - 1 transistors name symbol inside view name symbol inside view 2sb1132 r bar b c e 2sb1182 tl q b1182 b e c c e b b b e e c c b e c b c c e b e c g s d s d g (top...

  • Page 26

    Microphone 1 2 3 clr 4 5 6 7 8 9 ent 0 mr down up pwr sql anl bank f 9 - 1 9 - 1 logic unit • top view the combination of this page and the next page shows the unit layout in the same configuration as the actual p.C. Board. Section 9 board layouts *ic-a5/a23-chg 00.8.23 5:31 pm page 9-1.

  • Page 27

    9 - 2 40 21 20 1 14 +5v hv vcc 40 21 20 1 ce sba tt chgc txc s d ata vcc vcc unlk pck pstb p d ata extmic gnd +5v hv hv vordet rfdet voron rssi jackdet volck rfstb sck volda t a gnd gnd ptt extptt light dastb gnd gnd gnd vrec gnd beep mod gnd gnd to rf unit j3 up e down channel chassis s1 • bottom v...

  • Page 28

    9 - 3 ext sp/mic j2 antenna battery bp-200l 9—9.6 v j3 40 21 20 1 ce sba tt chgc txc s d ata vcc vcc unlk pck pstb p d ata extmic gnd +5v hv hv vordet rfdet voron rssi jackdet volck rfstb sck volda t a gnd gnd ptt extptt light dastb gnd gnd gnd vrec gnd beep mod gnd gnd to rf unit j3 j1 dc in 9 — 12...

  • Page 29

    9 - 4 3 2 7 1 4 5 6 chg 1 2 3 mp1 battery bp—200l 9—9.6 v ext sp/mic j2 • bottom view the combination of this page and the previous page shows the unit layout in the same configuration as the actual p.C. Board. *ic-a5/a23-chg 00.8.23 5:35 pm page 9-7.

  • Page 30

    10 - 1 1st mix ic1: ta31136fn vco rf unit logic unit cpu ic1: m38267m6l ant 1st if 30.05 mhz chassis unit 2nd mix pllda, pllck, pllst 2nd if amp (450 khz) 2nd.Lo 29.6 mhz embi afc wxc anlc txc key matrix up down vordet voron voro vors vorc rec/play micmute alcc clout plin af power out ext mic & clon...

  • Page 31

    C10 0.001 c11 0.001 c12 0.001 c13 0.001 c18 0.001 ds1 ttr3845upfdcn seg29 seg28 seg27 seg26 seg31 seg25 seg24 seg23 seg22 seg39 seg38 seg37 seg36 seg21 seg20 seg19 seg18 seg30 seg17 seg16 seg15 seg14 seg13 seg12 seg1 1 seg10 seg9 seg8 seg7 seg6 seg1 seg5 seg4 seg0 seg3 seg2 com3 com2 com1 com0 10 11...

  • Page 32

    C91 0.0047 r48 100k r58 100k r59 100k c93 1 c100 0.001 r52 120k r109 100k c99 0.001 c90 10 c92 0.001 r46 tbps1r104k475h5q r45 33k c89 0.001 r69 18k c116 0.001 c117 0.1 c123 0.001 r71 18k r70 180k c118 0.0047 r72 4.7k c98 0.1 sp— vcca mic mic ref agc ana in ana out nc playl playe recled xclk rec vccd...

  • Page 33

    C10 0.001 c11 0.001 c12 0.001 c13 0.001 c18 0.001 ds1 ttr3845upfdcn seg29 seg28 seg27 seg26 seg31 seg25 seg24 seg23 seg22 seg39 seg38 seg37 seg36 seg21 seg20 seg19 seg18 seg30 seg17 seg16 seg15 seg14 seg13 seg12 seg1 1 seg10 seg9 seg8 seg7 seg6 seg1 seg5 seg4 seg0 seg3 seg2 com3 com2 com1 com0 10 11...

  • Page 34

    9.3v tx: 3.2v rx: 0.0v tx: 0.0v rx: 0.2v tx: 0.0v rx: 4.4v tx: 0.0v rx: 0.1v tx: 0.0v rx: 1.2v tx: 0.0v rx: 0.2v tx: 0.0v rx: 4.2v tx: 0.0v rx: 1.2v tx: 0.0v rx: 0.2v tx: 0.0v rx: 1.4v tx: 0.0v rx: 4.8v tx: 9.1v rx: 9.2v tx: 0.0v rx: 2.5v tx: 3.2v rx: 0.0v tx: 3.5v rx: 0.0v tx: 4.9v rx: 0.0v 1.2v 5....

  • Page 35

    Tx: 1.8v rx: 0.0v tx: 0.0v rx: 1.2v tx: 0.0v rx: 4.8v tx: 0.0v rx: 0.0v tx: 0.0v rx: 0.2v tx: 0.0v rx: 4.4v tx: 0.0v rx: 0.1v 9.6v tx: 9.0v rx: 2.1v tx: 9.0v rx: 9.3v tx: 8.3v rx: 8.7v tx: 9.1v rx: 9.2v 9.3v input: 9.6v c9 0.001 c13 15p c15 1p c14 15p c11 1p c12 1p c16 0.5p c18 0.001 c28 0.001 c20 0...

  • Page 36

    9.3v tx: 3.2v rx: 0.0v tx: 1.8v rx: 0.0v tx: 0.0v rx: 1.2v tx: 0.0v rx: 4.8v tx: 0.0v rx: 0.0v tx: 0.0v rx: 0.2v tx: 0.0v rx: 4.4v tx: 0.0v rx: 0.1v tx: 0.0v rx: 1.2v tx: 0.0v rx: 0.2v tx: 0.0v rx: 4.2v tx: 0.0v rx: 1.2v tx: 0.0v rx: 0.2v tx: 0.0v rx: 1.4v tx: 0.0v rx: 4.8v 9.6v tx: 9.0v rx: 2.1v tx...

  • Page 37

    6-9-16, kamihigashi, hirano-ku, osaka 547-0002, japan phone : 06 6793 5302 fax : 06 6793 0013 url : http://www.Icom.Co.Jp/world/index.Html communication equipment himmelgeister str. 100, d-40225 d sseldorf, germany phone : 0211 346047 fax : 0211 333639 url : http://www.Icomeurope.Com unit 9, sea st....

  • Page 38

    13706mz-cd ' 2000 icom inc. 6-9-16, kamihigashi, hirano-ku, osaka 547-0002, japan count on us! Ic-a5 air band fm transceiver ic-a23 ic-a23 ic-a5.