IC-T90A_SM.pdf

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1、S-13903MZ-C1 2002 Icom Inc.1-1-32, Kamiminami, Hirano-ku, Osaka 547-0003, Japan MULTIBAND FM TRANSCEIVER iC-t90a iC-t90a IC-T90A (1,4) INTRODUCTION This service manual describes the latest service information for the IC-T90A MULTIBAND FM TRANSCEIVER at the time of publication. T90A U.S.A. General Ca

2、nada S.E. Asia USA GEN CAN SEA To upgrade quality, all electrical or mechanical parts and inter- nal circuits are subject to change without notice or obligation. DANGER NEVER connect the transceiver to an AC outlet or to a DC power supply that uses more than 12 V. Such a connection could cause a fir

3、e hazard and/or electric. DO NOT expose the transceiver to rain, snow or any liquids. DO NOT reverse the polarities of the power supply when connecting the tranceiver. DO NOT apply an RF signal of more than 20 dBm (100 mW) to the antenna connector. This could damage the transceiver s front end. ORDE

4、RING PARTS Be sure to include the following four points when ordering replacement parts: 1. 10-digit order numbers 2. Component part number and name 3. Equipment model name and unit name 4. Quantity required 1130006220S.IC TC4W53FUIC-T90ALOGIC UNIT1 piece 89300542902372 Main sealIC-T90AChassis5 piec

5、es Addresses are provided on the inside back cover for your convenience. REPAIR NOTES 1. Make sure a problem is internal before disassembling the transceiver. 2. DO NOT open the transceiver until the transceiver is disconnected from its power source. 3. DO NOT force any of the variable components. T

6、urn them slowly and smoothly. 4. DO NOT short any circuits or electronic parts. An insulated tuning tool MUST be used for all adjustments. 5. DO NOT keep power ON for a long time when the transceiver is defective. 6. DO NOT transmit power into a signal generator or a sweep generator. 7. ALWAYS conne

7、ct a 40 dB or 50 dB attenuator between the transceiver and a deviation meter or spectrum analyser when using such test equipment. 8. READ the instructions of test equipment thoroughly before connecting equipment to the transceiver. Communication Equipment Himmelgeister Str. 100, D-40225 D sseldorf,

8、Germany Phone: 0211 346047Fax : 0211 333639 URL: 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 5804, 31505 Toulouse Cedex, France Phone: 561 36 03 03Fax : 561 36 03 00 URL: http:/ww

9、w.icom- Crta. de Gracia a Manresa Km. 14,750 08190 Sant Cugat del Valles Barcelona, SPAIN Phone: (93) 590 26 70 Fax : (93) 589 04 46 URL: 2380 116th Avenue N.E., Bellevue, WA 98004, U.S.A. Phone: (425) 454-8155Fax : (425) 454-1509 URL: Phone: (425) 454-7619 Glenwood Centre #150-6165 Highway 17 Delta

10、, B.C., V4K 5B8, Canada Phone: (604) 952-4266Fax : (604) 952-0090 URL: A.B.N. 88 006 092 575 290-294 Albert Street, Brunswick, Victoria, 3056, Australia Phone: 03 9387 0666Fax : 03 9387 0022 URL: .au 146A Harris Road, East Tamaki, Auckland, New Zealand Phone: 09 274 4062Fax : 09 274 4708 URL: http:/

11、www.icom.co.nz 6F No. 68, Sec. 1 Cheng-Teh Road, Taipei, Taiwan, R.O.C. Phone: (02) 2559 1899Fax : (02) 2559 1874 1-1-32, Kamiminami, Hirano-ku, Osaka 547-0003, Japan Phone : 06 6793 5302 Fax: 06 6793 0013 URL: http:/www.icom.co.jp/world/index.html MODELVERSIONSYMBOL IC-T90A (2,3) TABLE OF CONTENTS

12、SECTION 1 SPECIFICATIONS SECTION 2INSIDE VIEWS SECTION3 DISASSEMBLY INSTRUCTIONS SECTION 4CIRCUIT DESCRIPTION 4 - 1 RECEIVER CIRCUITS . 4 - 1 4 - 2 TRANSMITTER CIRCUITS . 4 - 4 4 - 3 PLL CIRCUITS. 4 - 5 4 - 4 POWER SUPPLY CIRCUITS . 4 - 7 4 - 5 PORT ALLOCATIONS. 4 - 7 SECTION 5ADJUSTMENT PROCEDURES

13、5 - 1 PREPARATION. 5 - 1 5 - 2 TRIMMER ADJUSTMENT. 5 - 3 5 - 3 ADJUSTMENT MODE ADJUSTMENTS . 5 - 5 SECTION 6PARTS LIST SECTION 7 MECHANICAL PARTS AND DISASSEMBLY SECTION 8SEMI-CONDUCTOR INFORMATION SECTION 9 BOARD LAYOUTS 9 - 1 LOGIC UNIT . 9 - 1 9 - 2 RF UNIT. 9 - 3 9 - 3 AF UNIT / VCO UNIT . 9 - 5

14、 SECTION 10 BLOCK DIAGRAM SECTION 11 VOLTAGE DIAGRAM 1 - 1 MGENERAL Frequency range:(Unit: MHz) * 1Specifications guaranteed 144 148 MHz * 2Specifications guaranteed 440 450 MHz * 3Specifications guaranteed 430 440 MHz * 4Except 824 849 MHz, 869 894 MHz USA only Mode: FM, AM (RX only) and WFM (Rx on

15、ly) Number of memory channels: 555 (incl. 50 scan edges and 5 call channels) Frequency stability: 6 ppm max. (10C to +60C; 14F to 140F) Tuning steps: 5, 6.25, 8.33, 9, 10, 12.5, 15, 20, 25, 30, 50 100, and 200 kHz Usable tempareture range: 10C to +60C; 14F to 140F Power supply requirement: 5.5 11 V

16、DC or specified battery pack Usable battery pack/case: BP-217 (7.4 V) and BP-216 (3.2 V) Polarity: Negative ground Current drain (at 8.0 V DC) : (typical value) * 1Power save duty is 1:4. Anntena connector: SMA (50 ) Dimensions (projections not included): 58(W) 87(H) 29(D) mm;21732(W) 3716(H) 1532(D

17、) in Weight (with BP-217/Ant.): 280 g; 978oz MTRANSMITTER Output power (at 8.0 V DC): High5.0 W typical Low0.5 W typical Modulation system:Variable reactance modulation Max. freq. deviation: 5 kHz Spurious Emissions: Less than 60 dB External MIC connector: 3-conductor 2.5(d) mm (18”); 2 k SECTION 1S

18、PECIFICATIONS 440 MHz 2.0 A 1.2 A RX High power Low power Rated output Standby Power saved* 1 50/145 MHz 2.0 A 0.8 A 220 mA 100 mA 65 mA Version USA CAN GEN SEA 50 MHz 50 53.995 145 MHz 144 148 136 174* 1 140 150* 1 440 MHz 430 450* 2 400 470* 3 430 440 Receiving 0.495999.990* 4 TX 1 - 2 All stated

19、specifications are subject to change without notice or obligation. MRECEIVER Receiver system: Double-conversion superheterodyne Intermediate frequency : 1st13.350 MHz (FM/AM) 13.350 MHz (WFM) 2nd450 kHz Sensitivity* 1: (except spurious points; typical values) * 1 FM and WFM are measured at 12 dB SIN

20、AD, AM is mea- sured at 10 dB S/N. * 2 The frequency range is between 222.000 MHz and 229.995 MHz. * 3 The frequency range is between 320.000 MHz and 329.995 MHz. * 4 The frequency range is between 40.000 MHz and 108.000 MHz. Selectivity AM and FM: Less than 15 kHz/9 dB More than 30 kHz/60 dB WFM: L

21、ess than 350 kHz/3 dB More than 700 kHz/20 dB Spurious and image rejection ratio : 50 MHzMore than 60 dB IF/2: More than 50 dB IF: More than 40 dB 145 MHzMore than 60 dB IF/2: More than 50 dB 440 MHzMore than 50 dB IF: More than 60 dB Audio output power: 200 mW typical at 10 % distor- tion with an 8

22、 load AF output impedance: 8 Squelch sensitivity* 1: (typical; Except sprious points) * 1 FM and WFM are measured at 12 dB SINAD, AM is mea- sured at 10 dB S/N. * 2 The frequency range is between 222.000 MHz and 229.995 MHz. * 3 The frequency range is between 320.000 MHz and 330.000 MHz. * 4 The fre

23、quency range is between 40.000 MHz and 108.000 MHz. Frequency (MHz) 0.4951.625 1.6254.995 5.00029.995 29.99549.995 50.00054.000 54.00576.000 76.000108.000 108.000118.000 118.000136.000 136.000143.995 144.000148.000 148.005175.000 175.000221.995 222.000225.000 225.005246.995 247.000329.995 329.995429

24、.995 430.000450.000 450.005470.000 470.000770.000 770.000832.995 833.000999.990 FM 0.4 V 0.18 V 0.16 V 0.18 V 0.16 V 0.4 V 0.32 V 0.4 V 0.32 V 0.16 V 0.32 V 1.0 V AM 1.3 V 0.56 V 0.5 V 0.79 V* 2 1.0 V* 3 WFM 1.0 V* 4 1.8 V 3.2 V Frequency (MHz) 0.4951.625 1.6254.995 5.00029.995 29.99549.995 50.00054

25、.000 54.00576.000 76.000108.000 108.000118.000 118.000136.000 136.000143.995 144.000148.000 148.005175.000 175.000221.995 222.000225.000 225.005246.995 247.000329.995 329.995429.995 430.000450.000 450.005470.000 470.000770.000 770.000832.995 833.0001319.995 FM 0.4 V 0.18 V 0.16 V 0.18 V 0.16 V 0.4 V

26、 0.32 V 0.4 V 0.32 V 0.16 V 0.32 V 1.0 V AM 1.3 V 0.56 V 0.5 V 0.79 V* 2 1.0 V* 3 WFM 1.0 V* 4 1.8 V 3.2 V 2 - 1 SECTION 2INSIDE VIEWS EEPROM (IC2: HN58X24128FPI, Q2: UN9115) RESET IC (IC142: S-80928CNMC) Crystal oscillator for CPU clock (X1: CR-687, 6.7584 MHz, Q40: UN9215) CPU (IC1: M30220MA-114RP

27、) AF regulator (Q201: 2SB1201, Q202: XP1501) +3 regulator (Q8: 2SB1132, Q9: XP1501) +3C regulator (Q142: XP1501, Q145: 2SB1132, D143: MA2S111) CPU3 regulator (IC141: NJM2370U32) 440 MHz band modulation switch (Q304: 2SJ364) Microphone mute (Q310: XP6501) Microphone amplifier (Q311: XP5601, Q312: XP6

28、501) 145 MHz band modulation switch (Q305: 2SJ364) 50 MHz band modulation switch (Q342: 2SJ364) LOGIC UNIT Top view LOGIC UNIT Bottom view 2 - 2 50 MHz TX low-pass filter circuit 144 MHz TX high-pass filter circuit Pre-drive (Q54: 2SC5289) Drive amplifier (Q52: 2SK3475) 0.49529.995 MHz RF amplifier

29、(Q302: 2SC5006) 75.995229.995 MHz RF amplifier (Q351: 3SK320) R3 regulator (Q353: XP4312) 29.99575.995 MHz RF amplifier (Q303: 2SC5006) 629.995999.90 MHz RF amplifier (Q452: 2SK3475) T3 regulator (Q56: XP4315, D50: MA6S121) 1st mixer (IC351: PC2757TB) VCO circuit Power amplifier (Q51: 2SK3476) FM IF

30、 IC (IC151: TA31136FN) 1st AF amplifier (Q205: 2SD2216) AF mute (Q251: 2SJ364) IF amplifier (Q102: 2SC4403) T5V regulator (Q11: XP1501, Q55: 2SB1132) Crystal oscillator (X1: VR-583, 13.800 MHz) AF power amplifier (IC252: TA7368F) AM/FM switch (Q206: XP4315) R3V regulator Q208: 2SA1576 Q209: XP1501 A

31、M detector (Q201, Q202: XP6501) AF UNIT Top view RF UNIT Top view AF UNIT Bottom view AF UNIT Bottom view RF UNIT Bottom view 3 - 1 SECTION 3DISASSEMBLY INSTRUCTIONS 1. Removing the rear panel 2. Removing the LOGIC unit 3. Removing the AF unit 4. Removing the RF unit q Unscrew 1 screw A (M2 4 mm, bl

32、ack). w Unscrew 2 screws B (M2 20 mm, black), and 4 screws C (M2 6 mm, black) from the rear panel. e Take off the rear panel in the direction of the arrow. q Unplug the flexible cable W1 from J1 on the LOGIC unit to separate the rear panel. w Take off the main seal. e Unsolder 2 points D at the spea

33、ker lead. r Unscrew 6 screws E (2 4 mm, silver) to separate the LOGIC unit. NOTE: When you tighten 6 screws E, tighten those in turn of 16. q Take off the lock plate. w Unsolder 5 points F at the antenna plate, vol plate and lead. e Unscrew 1 screw G (2 4 mm, silver), and 2 screws H (M2 12 mm, black

34、) from the AF unit. r Take off the AF unit in the direction of the arrow to sepa- rate the rear panel. q Unsolder 2 points I at the antenna rug plate and anten- na connector. w Unscrew 2 screws J (M2 4 mm, silver) from the FRONT panel. e Take off the RF unit in the direction of the arrow to sepa- ra

35、te the rear panel. Rear panel A B C W1 (L) J1 Main seal E E 2 3 4 5 LOGIC unit 1 6 D G J251 Lock plate Rear panel AF unit Vol plate Vol lead Antenna plate F F F H J RF unit Antenna rug Antenna connector Rear panel I SECTION 4CIRCUIT DESCRIPTION 4 - 1 4-1 RECEIVER CIRCUITS 4-1-1 TRIPLEXER CIRCUIT (RF

36、 UNIT) The transceiver has a triplexer (low-pass and bandpass fil- ters) on the first stage from the antenna switching diode to separate the signals. RF signals 0.495 MHz75.995 MHz The 0.495 MHz75.995 MHz RF signals are passed through the low-pass filters (L5, L6, L24, C43, C483C486, L11L13, L17L19,

37、 C21, C481, C482) and are applied to the antenna switching circuit. RF signals 76.0 MHz299.995 MHz The 76.0 MHz299.995 MHz RF signals are passed through the low-pass (L5, L6, L24, C43, C483C486) and high-pass (L9, C9C11) filters and are applied to the antenna switching circuit. RF signals 230.0 MHz6

38、29.995 MHz The 230.0 MHz629.995 MHz RF signals are passed through the high-pass (L1, C1C3) and low-pass (FI1) filters and are applied to the antenna switching circuit. RF signals 630.0 MHz999.990 MHz The 630.0 MHz999.990 MHz RF signals are passed through the high-pass (L3, L4, C6C8) filter and are a

39、pplied to the RF circuit. 4-1-2 ANTENNA SWITCHING CIRCUIT (RF UNIT) The antenna switching circuit functions as a low-pass filter while receiving. However, its impedance becomes very high while transmitting by applying a current to D4, D6, D9, D12, D13, D19. Thus, tramsmit signals are blocked from th

40、e entering the receiver circuits. The antenna switching circuit employs a 1/4 type diode switching system. The signals are applied to the each antenna switching circuit. RF signals 0.495 MHz75.995 MHz The signals pass through the antenna switching circuit (D9), and then applied to the RF circuit. RF

41、 signals 76.0 MHz299.995 MHz The signals pass through the antenna switching circuit (D8), and then applied to the RF circuit. RF signals 230.0.0 MHz629.995 MHz The signals pass through the antenna switching circuit (D7), and then applied to the RF circuit. 4-1-3 RF CIRCUIT (RF UNIT) The RF circuit a

42、mplifies the received signals within the range of frequency coverage and filters out-of-band signals. (1) 0.495 MHz29.995 MHz RF CIRCUIT The signals from the antenna switching circuit pass through the attenuator (D305) and band switch (D301). The signals applied to the bandpass filter (L301, L302, C

43、301C307) to suppress unwanted signals, then amplified at the RF amplifi- er (Q302). (2) 30.0 MHz75.995 MHz RF CIRCUIT The signals from the antenna switching circuit pass through the attenuator (D305) and band switch (D306). The signals applied to the bandpass filter (D307, D308, L303, L304, C317C320

44、) to suppress unwanted signals, then pass through the bandpass filter (D309, D310, L306, L307, L323C325, C331) after being amplified at the RF amplifier (Q303). ANT LPFLPF ATT CTRL HPF HPF HPF LIMIT LIMIT ANT SW LPF ANT SW ANT SW LIMIT LIMITSW SW 75.995 MHz RF signals 299.995 MHz RF signals 629.995

45、MHz RF signals 999.990 MHz RF signals 0.495 MHz 76.0 MHz 230.0 MHz 630.0 MHz R3V Q355 Antenna switching circuit Triplexer circuit D305 D351 D401 D451 D6, D9 D4, D19 D12, D13D457 D10 ATT TRIPLEXER AND ANTENNA SWITCHING CIRCUITS 4 - 2 (3) 76.0 MHz229.995 MHz RF CIRCUIT The signals from the antenna switching circuit pass through the attenuator (D351), and then applied to the bandpass fil- ter (D352, D353, L351, L352) to suppress unwanted signals. The signals pass through the bandpass filter (D354D356, D359, L354, L355, L357, L358, C357C364) after being amplified a