Page 2 - DO NOT expose the transceiver to rain, snow or any liquids.; ORDERING PARTS; REPAIR NOTES
INTRODUCTION This service manual describes the latest service informationfor the IC-910H VHF/UHF ALL MODE TRANSCEIVER at thetime of publication. VERSION No. #02 #04 #06 #07 VERSION Europe Australia U.S.A. Korea SYMBOL EUR AUS USA-1 KOR To upgrade quality, any electrical or mechanical parts andintern...
Page 3 - TABLE OF CONTENTS
SECTION 1 SPECIFICATIONS SECTION 2 INSIDE VIEWS 2 - 1 IC-910H . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 1 2 - 2 UX-910 (OPTIONAL UNIT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....
Page 4 - SECTION 1 SPECIFICATIONS; GENERAL; Version
SECTION 1 SPECIFICATIONS 1 - 1 ■ GENERAL • Frequency coverage : (Unit: MHz) * 1 Optional UX-910 is installed. * 2 Guaranteed range is 144.0–148.0 MHz. * 3 Guaranteed range is 430.0–450.0 MHz. * 4 Guaranteed range is 1240.0–1300.0 MHz. • Mode : USB, LSB, CW, FM, FM-N* *Not available in 1200 MHz band ...
Page 5 - RECEIVER; MAIN BAND
■ RECEIVER • Receive system : VHF SSB, CW Single conversion superheterodyne FM Double conversion superheterodyne UHF SSB, CW Double conversion superheterodyne FM Triple conversion superheterodyne • Intermediate frequencies : (Unit: MHz) • Sensitivity : SSB, CW (10 dB S/N) Less than 0.11 µV FM (12 dB...
Page 6 - • MAIN AND PLL UNITS
2 - 1 SECTION 2 INSIDE VIEWS 2-1 IC-910H • MAIN AND PLL UNITS DDS IC (IC701: SC-1287) DDS gate arr a y (IC131: SC-1246A) DDS gate arr a y (IC331: SC-1246A) PLL unit 144 MHz band VCO circuit 430 MHz band VCO circuit Ref erence oscillator (X512: CR-452 30.2 MHz) Dr iv er IC (IC1: B U4094BCF) DDS IC (I...
Page 7 - • PA UNIT
2 - 2 • PA UNIT TX balanced mix er Q501, Q502: 2SK302 D502: 1SV286 RX balanced mix er (Q511, Q512: 2SK1740) Pre-amplifier (Q507: 3SK177) 145 MHz po w er amplifier (Q651, Q652: 2SC5152) TX/RX s witching rela y (RL700: AE5349) V a ristor-A board V a ristor-C board 440 MHz po w er amplifier (Q151, Q152...
Page 9 - • Opening the transceiver’s case; Turn the transceiver upside down.; DISCONNECT the DC power cable; Remove the bottom cover as shown above.; CAUTION; Place the UX-910 using the supplied 4 screws.
SECTION 3 DISASSEMBLY AND OPTION INSTRUCTIONS • Opening the transceiver’s case Follow the case and cover opening proceduresshown here when you want to install an optional unitor adjust the internal units, etc. q Remove the 5 screws from the top of the trans-ceiver and 4 screws from the sides, then l...
Page 10 - • Opening the PA unit cover; Remove fastening tape from the inside power cable.; BE CAREFUL not to pinch your finger with the clip.; Slide the PA unit cover as shown below.
• Opening the PA unit cover q Remove the top cover as shown in the diagram on p. 3-1. w Remove 8 screws and grounding plate from the PA unitcover. e Remove fastening tape from the inside power cable. grounding plate • FL-132/FL-133 CW NARROW FILTER q Remove the bottom cover as shown in the diagram o...
Page 11 - • UT-102 VOICE SYNTHESIZER UNIT; Return the bottom cover to its original position.; Installing 1st DSP unit (front panel side); Installing 2nd DSP unit (rear panel side); Remove the shielding plate.
• UT-102 VOICE SYNTHESIZER UNIT q Remove the bottom cover as shown in the diagram on p. 3-1. • Remove the UX-910 if you have installed it. (p. 3-1) w Remove the protective paper attached to the bottom ofthe UT-102 to expose the adhesive strip. e Plug UT-102 into J1801 on the MAIN unit as shown in th...
Page 12 - • CR-293 HIGH STABILITY CRYSTAL UNIT
• CR-293 HIGH STABILITY CRYSTAL UNIT q Remove the bottom cover as shown in the diagram on p. 3-1. • Remove the UX-910 if you have installed it. (p. 3-1) w Remove 6 screws from the PLL shield cover, then lift upthe PLL shield cover. PLL shieldcover e Disconnect the FFC (Flexible Flat Cable) from the ...
Page 13 - SECTION 4 CIRCUIT DESCRIPTION; • RECEIVER CONSTRUCTION; MAIN unit
SECTION 4 CIRCUIT DESCRIPTION 4 - 1 4-1 RECEIVER CIRCUIT Note: [Main]=Main band, [Sub]=Sub band 4-1-1 VHF TRANSMIT/RECEIVE SWITCHING CIRCUIT (PA UNIT) Received signals from the antenna connector (CHASSIS;J1) are passed through the low-pass filter (L723–L721,C728–C726, C728) then applied to the trans...
Page 14 - USB
4 - 2 4-1-6 10 MHz IF CIRCUIT (MAIN UNIT) The 10 MHz IF signal from the mixer circuit is passedthrough a monolithic filter (Fl51 [Main], Fl651 [Sub]) to sup-press out-of-band signals. The filtered signal is amplified atthe IF amplifier (Q51 [Main], Q651 [Sub]). The IF amplifierprovides 20 dB gain. T...
Page 15 - -2 TRANSMITTER CIRCUITS; • AGC CIRCUIT FOR MAIN BAND
4 - 3 4-1-11 NOISE BLANKER CIRCUIT (MAIN UNIT) The noise blanker circuit detects pulse-type noises, andstops IF amplifier operation during detection. A portion of the 10 MHz IF signal from the bandpass filter(FI51 [Main], FI651 [Sub]) is amplified at the noise amplifiercircuit (Q102, IC101, Q101 [Ma...
Page 19 - SECTION 5 ADJUSTMENT PROCEDURES; -1 PREPARATION BEFORE SARVICING; REQUIRED TEST EQUIPMENT; EQUIPMENT; CONNECTIONS; DO NOT; TERMINATOR
SECTION 5 ADJUSTMENT PROCEDURES 5 - 1 4-1 PREPARATION BEFORE SARVICING ■ REQUIRED TEST EQUIPMENT DC power supply RF power meter(terminated type) Frequency counter RF voltmeter FM deviation meter Distortion meter Oscilloscope Digital multimeter Audio generator Standard signal generator (SSG) AC milli...
Page 20 - -3 FREQUENCY ADJUSTMENT
5 - 2 5-2 PLL ADJUSTMENTS 30.2 MHzLEVEL REFERENCEFREQUENCY 144M LOCKVOLTAGE 440M LOCKVOLTAGE MAIN BFOLEVEL SUB BFOLEVEL ADJUSTMENT ADJUSTMENT ADJUSTMENT CONDITION MEASUREMENT VALUE POINT UNIT LOCATION UNIT ADJUST 1 1 2 1 2 3 1 2 3 1 2 • Display frequency: Any• Receiving • Display frequency: Any• Rec...
Page 21 - • PLL AND MAIN UNITS
5 - 3 X512 Reference frequency adjustment C402 430M lock voltage adjustment P251 144M LO level check point L193 144M lock voltage adjustment J541 30.2 MHz level check point CP300 430M lock voltage check point P421 430M LO level check point L551 J51 CP51 FM TX-LOfrequencycheck point J52 FM TX-LOfrequ...
Page 22 - -4 RECEIVER ADJUSTMENTS
*This output level of a standard signal generator (SSG) is indicated as SSG’s open circuit. 5 - 4 5-4 RECEIVER ADJUSTMENTS Receiver adjustments must be performed after software adjustment (0) and (1). SUB band must be OFF when adjusting MAIN band,or main AF volume (max.counter clockwise) and SQL vol...
Page 26 - -5 TRANSMITTER ADJUSTMENTS
PA UNITPRESETTING IDLINGCURRENT(for 144 M) (for 430 M) RF PEAK(for 430 M) (for 144 M) IF PEAK CARRIERSUPPRESSION • Preset R131, R135, R150, R650 (PA unit) to max. counter clockwise.• Preset R3, R138, R503 (PA unit) to center position.• Preset C154, C659 (PA unit) to center position as illustration a...
Page 29 - IC APC adjustment
5 - 11 • PA UNIT • MAIN UNIT R3 Total gainadjustment for 430M IF total gain adjustment R3 IC APC adjustment IC APC pre-setting R1613 CP1613 Drive level adjustment R202 IF total gain/Drive level check point J51 R503 Total gainadjustment for 144M R504 LO leakadjustment for 144M P501 IF total gain/Driv...
Page 30 - -6 SOFTWARE ADJUSTMENT; ADJUSTMENT
*This output level of a standard signal generator (SSG) is indicated as SSG’s open circuit. 5 - 12 5-6 SOFTWARE ADJUSTMENT ENTERINGSOFTWAREADJUSTMENT ADJUSTMENTITEM (0) VOLUMECENTER PLL UNLOCK ADJUSTMENTITEM (1)TUNED BPF(for 144 M) (for 430 M) ADJUSTMENT ADJUSTMENT CONDITION DISPLAY OPERATION • Ente...
Page 33 - selection item screen
*This output level of a standard signal generator (SSG) is indicated as SSG’s open circuit. 5 - 15 SOFTWARE ADJUSTMENT (continued) ADJUSTMENTITEM (4)CENTER(MAIN BAND) ADJUSTMENTITEM (5)FILTERCALIBRATION(MAIN BAND) (SUB BAND) ADJUSTMENT ADJUSTMENT CONDITION DISPLAY OPERATION • Connect an SSG to [VHF ...
Page 71 - Screw abbreviations
MP1 8930014140 Earth spring (D) 1 MP7* 8510012310 2157 DBM case 1 MP8* 8510013620 2355 A-filter case 1 MP9* 8510002020 MIX shield case 1 MP10* 8510012310 2157 DBM case 1 MP11* 8510013390 2355 MIX case 1 MP12* 8510013890 2355 V-A shield plate 1 MP13* 8510013630 2355 U-A shield plate 1 MP14 8510010460...
Page 72 - • TRANSISTORS AND FET’S; SECTION 8
8 - 1 • TRANSISTORS AND FET’S SECTION 8 SEMI-CONDUCTOR INFORMATION B E C B E C B E C B C E B E C B E C B B E E C C B E C B E C B E C B E E E E C B E C B E C B C E B E C B E C B E C B E C B E E E E C B E C B E C E C B E E C B E B E C B E C B C E B C E B C E B E C B E C S D G D G S S D G S D G D G S S...
Page 74 - • DIODES
8 - 3 • DIODES C A1 A2 A C C A1 A2 A pink C A C A1 A2 C1 C2 NC A C C A1 A2 A C A1 C2 C1 A1 C2 C1 A C A C A C A C A C A C A C A C A C A C A C A C A C red dot A C 1SS301 1SS355 1SS375-TL 1SS385 1SV214 1SV217 1SV237 1SV239 1SV265 TL 1SV286 1SV307 1SV308 DA221 DAN202 U T107 DAN222TL DAP202K T146 DAP222 ...
Page 75 - • TOP VIEW
9 - 1 9-1 VR-A BOARD SECTION 9 BOARD LAYOUTS • TOP VIEW GND J1 2 6 1 to DISPLAY board J2 5 MA VR NC NC MSVR +5V • TOP VIEW GND J1 2 6 1 to DISPLAY board J10 5 RIVR NC NC SFVR +5V 9-2 VR-B BOARD • TOP VIEW GND 2 J1 6 1 to DISPLAY board J11 5 SA VR NC NC SSVR +5V 9-3 RIT BOARD
Page 77 - Icom Canada
Communication EquipmentHimmelgeister Str. 100, D-40225 Düsseldorf, GermanyPhone : 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 741742URL : http://www.icomuk.co.uk Zac de la Plaine, Rue Brindejonc des Mou...