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SERVICE

MANUAL

DUAL BAND FM TRANSCEIVIER

Summary of Contents for IC-T7H

Page 1: ...SERVICE MANUAL DUAL BAND FM TRANSCEIVIER...

Page 2: ...IC T7H 1F UNIT 5pieces 8810008750 Screw PH BO 2 x 15 ZK IC T7H Chassis 10pieces Addresses are provided on the inside back cover for your convenience 1 Make sure a problem is internal before disassemb...

Page 3: ...CIRCUITS 4 4 4 5 OTHER CIRCUITS 4 4 4 6 PORT ALLOCATIONS 4 5 SECTION 5 ADJUSTMENT PROCEDURES 5 1 PLL AND TRANSMITTER ADJUSTMENT 5 1 5 2 RECEIVER ADJUSTMENT 5 3 SECTION 6 PARTS LIST SECTION 7 MECHANICA...

Page 4: ...174 MHz 1 136 MHz 174 MHz 1 400 MHz 470 MHz 3 F3 F2 5 ppm 5 10 12 5 15 20 25 30 or 50 kHz BNC 50 4 5 to 16 V DC 1 6 A typical 1 6 A typical 0 6 A typical 0 7 A typical 180 mA typical 190 mA typical 16...

Page 5: ...UHF band pass filter FI201 EFCH445MWN UHF RF amplifier Q201 2SC4226 Located under side of these points AF power amplifier IC151 2SC5226 VHF RF amplifier Q51 2SC5226 1st IF filter FI401 FL244 2nd IF f...

Page 6: ...n below REMOVING 2F UNIT 1 Unscrew 1 screw E from the 2F unit 2 Unsolder the point F then remove the 2F unit with the contact base Disconnect J1 on reverse side of the 2F unit to remove Rear panel C F...

Page 7: ...imit ter D201 and are then amplified at the the RF amplifier Q201 The amplified signals are passed through the band pass filter FI201 and are then applied to another RF ampli fier Q202 The amplified s...

Page 8: ...etects the signal level from the number of the pulses and outputs an MM RM signal from IC1 pin 44 on LOGIC unit This signal controls the AF mute switch LOGIC unit Q10 to cut the AF signal line 4 2 TRA...

Page 9: ...2 and Q204 are turned ON The signal passes through the low pass L7 L9 C9 C15 and high pass L1 L3 C1 C5 filters and is then applied to the antenna connector The high pass filter sup presses low harmoni...

Page 10: ...ltage is supplied to the 3C R3 and T4 regulator circuits etc Common 3 V converted from the VCC line by the 3C regulator circuit LOGIC unit Q4 Q5 Q40 and D3 using the 3CPU regulator LOGIC unit IC2 3 V...

Page 11: ...ow POWER switch is pushed Outputs LCD contrast control signals Input port for key matrix Input port for the PTT control circuit HIGH When transmitting Input port for reset circuit LOGIC unit IC3 pin 1...

Page 12: ...as HPF OFF LPF 20 kHz De emphasis OFF Detector P P 2 Output power High Transmitting Displayed frequency 445 000 MHz USA 3 435 000 MHz Other Output power High Transmitting Displayed frequency 445 000...

Page 13: ...QUENCY COUNTER 100 MHz 500 MHz 1F UNIT 2F UNIT RF POWER METER 10 W 50 FREQUENCY COUNTER 100 MHz 500 MHz R302 R304 VHF output power adjustment High UHF output power adjustment High ATTENUATOR 40 or 50...

Page 14: ...dBm Modulation 1 kHz Deviation 3 5 kHz Pre set the R504 to maxmum CW Receiving Displayed frequency 443 000 MHz USA 3 433 000 MHz Other Connect an SSG to the antenna connector and set as Level 0 5 V 1...

Page 15: ...R SSG 100 500 MHz 127 to 17 dBm 0 1 V to 32 mV CAUTION DO NOT transmit while the signal generator is connected L102 CP1 UHF sensitivity adjustment UHF sensitivity check point L53 L54 L55 VHF sensitivi...

Page 16: ...F15NK L702 6200005830 S COIL NLH252018T 012J 12N L703 6200004380 S COIL LL1608 F18NK L723 6200008080 S COIL LQN21A R22J04 L724 6200008080 S COIL LQN21A R22J04 L725 6200008080 S COIL LQN21A R22J04 L801...

Page 17: ...S CERAMIC C1005 JB 1E 102K T A C358 4030009810 S CERAMIC C1005 JB 1E 102K T A C359 4030009810 S CERAMIC C1005 JB 1E 102K T A C360 4030011600 S CERAMIC C1608 JB 1C 104KT N C361 4030009810 S CERAMIC C10...

Page 18: ...009780 S CERAMIC C1005 CH 1E 270J T A C302 4030010080 S CERAMIC C1005 CH 1E 240J T A C303 4030011670 S CERAMIC C1005 CH 1E 2R5B T A C304 4030011670 S CERAMIC C1005 CH 1E 2R5B T A C305 4030009810 S CER...

Page 19: ...17 7030005240 S RESISTOR ERJ2GEJ 473 X 47 k R118 7030005120 S RESISTOR ERJ2GEJ 102 X 1 k R119 7030004980 S RESISTOR ERJ2GEJ 101 X 100 R120 7030005220 S RESISTOR ERJ2GEJ 223 X 22 k R121 7030005240 S RE...

Page 20: ...30009810 S CERAMIC C1005 JB 1E 102K T A C406 4030009810 S CERAMIC C1005 JB 1E 102K T A C407 4030009810 S CERAMIC C1005 JB 1E 102K T A C408 4030009760 S CERAMIC C1005 CH 1E 150J T A C409 4030009810 S C...

Page 21: ...RJ3GEYJ 104 V 100 k R219 7030003840 S RESISTOR ERJ3GEYJ 225 V 2 2 M R220 7030003560 S RESISTOR ERJ3GEYJ 103 V 10 k R221 7030005520 S RESISTOR RR0816R 334 D 330 k R222 7030005970 S RESISTOR RR0816R 683...

Page 22: ...1005 JB 1E 102K T A C208 4030009810 S CERAMIC C1005 JB 1E 102K T A C209 4030009810 S CERAMIC C1005 JB 1E 102K T A C210 4030009810 S CERAMIC C1005 JB 1E 102K T A C211 4030009810 S CERAMIC C1005 JB 1E 1...

Page 23: ...PARTS REF NO ODER NO DESCRIPTION QTY J901 6450000130 Connector HSJ1102 01 540 MIC 1 J902 6450001060 Connector HSJ1493 01 010 SP 1 J903 6450000870 Connector HEC2711 01 020 DC13 5V 1 S1 7600000190 Encod...

Page 24: ...MP1 C MP8 C MP9 C MP21 C MP13 C MP13 C MP13 C MP12 C MP29 C MP1 1F MP2 1F J902 1F S1 1F J903 1F MP301 D J901 1F MP19 C MP24 C MC1 L W1 L J1 C J1 C LOGIC UNIT MP11 L SP1 L MP12 L MP13 L MP15 C MP401 P...

Page 25: ...mbol R25 2SC4228 R45 Symbol R45 2SC4403 3 Symbol LY3 2SB1132 R Symbol BARB 2SB1201 S Symbol B1201 2SB1462 R Symbol BR 2SC3356 R25 Symbol R25 TRANSISTOR AND FET S S D G B E C B E C B1 E B2 C1 C2 E1 E2...

Page 26: ...SECTION 9 BOARD LAYOUTS 9 1 DS1 DS4 MC1 DS3 DS2 C91 C92 C93 S1 C81 C80 C83 C82 9 1 LOGIC UNIT TOP VIEW...

Page 27: ...C157 D19 C207 R207 Q4 C141 Q12 Q10 Q40 C208 R12 C19 C15 C169 C170 C180 Q45 C172 C178 R216 R240 R215 R213 R214 R242 R187 C179 C181 C154 R181 R186 C206 R241 R211 C171 D3 IC13 IC12 HD17 D13 D16 D7 D14 C1...

Page 28: ...Q305 R306 MOD S B5216A C414 C415 C922 FI101 800 300 AF MOD EXTMIC SPE INTSP AFON PLST PLCK PDA UL REMOTE DICK DIUD AM UR3 VR3 LVCO 3C HVCO TXC SHIFT VCC H L TXSEL DETO NOISE SD GND GND 30 1 TO LOGIC U...

Page 29: ...117 R116 R118 R119 R122 C121 C12 Q104 Q102 C124 C923 Q103 Q105 C106 D402 D401 C11 Q4 Q5 C123 C126 R5 C122 C413 C406 C406 C405 R408 R406 C402 C400 R612 R402 C416 C67 C65 R59 C63 C61 R101 R102 R110 R112...

Page 30: ...C380 R374 C376 C377 C379 C378 L355 Q356 L353 C554 C553 R210 D552 D201 D51 D351 D52 VRF GND GND 800M GND URF C101 Q253 C910 C102 S1 J904 J904 L900 1 C861 R362 R363 R863 R862 J903 C865 UOUT GND VOUT GN...

Page 31: ...C7 IC250 C371 C370 C904 C906 R365 C8 D1 C551 C15 C13 C14 C552 D551 C5 C4 C2 C3 C9 L2 L7 L8 L9 L724 L723 L551 L3 C10 C12 R728 R721 C724 C728 R726 R727 C911 C730 C727 R724 R262 R267 C214 R704 R708 R278...

Page 32: ...3 IC151 TA7368F 2F UNIT TO BATT VCC Q10 2SJ364 Q12 XP6501 CTCIN R3 5 IC13 NJM2904M IC12 BA4510F VCC R3 REG 3C 3C VCC MIC AMP MUTE SW IC12 BA4510F Q31 UN9211 D901 RB060L 40 HV REVERS VOLT PROTECT MC1 E...

Page 33: ...C201 0 001 C202 0 001 C216 0 001 C217 0 001 R216 1 M R211 470 k R215 82 k R214 82 k R213 82 k 1 5 6 7 8 IC13 NJM2904M R241 100 k C181 0 01 C180 0 1 C172 0 1 R219 2 2 M C173 0 0022 C169 0 0015 C170 0 1...

Page 34: ...R250 0 15 D250 MA8030H C235 0 001 C2360 001 C234 0 001 R251 68 k R252 47 k 1 2 3 4 6 5 7 8 IC250 NJM2904M R265 4 7 k R261 1 M R264 2 2 k C254 0 001 R267 15 k R263 10 k Q255 2SB1462 R C231 0 001 C232...

Page 35: ...1 MA2S077 C56 0 001 R51 68 k D52 MA304 Q51 2SC5226 4 C58 0 001 R52 100 k C59 0 001 R53 68 L53 LS 518 VRF C55 0 001 C54 10 P D55 1SV271 C69 9 P C57 12 P R57 33 k C60 0 001 R56 10 k R55 330 R54 100 Q52...

Page 36: ...Australia Phone 03 9387 0666 Fax 03 9387 0022 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 Moulinais BP 58...

Page 37: ...6 9 16 Kamihigashi Hirano ku Osaka 547 0002 Japan A 5551I S Printed in Japan 1998 by Icom Inc...

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