IC7700_serv.pdf

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1、S-14407XZ-C1 Feb. 2008 HF/50MHz TRANSCEIVER This service manual describes the latest service information for the IC-7700 HF/50MHz TRANSCEIVER at the time of publication. NEVER connect the transceiver to an AC outlet or to a DC power supply that uses more than specifed. This will ruin the transceiver

2、. DO NOT expose the transceiver to rain, snow or any liquids. DO NOT reverse the polarities of the power supply when connecting the transceiver. DO NOT apply an RF signal of more than 20 dBm (100 mW) to the antenna connector. This could damage the transceivers front-end. To upgrade quality, any elec

3、trical or mechanical parts and internal circuits are subject to change without notice or obligation. MODELVERSION IC-7700 USA EUR FRA ITR ESP UK KOR Be sure to include the following four points when ordering replacement parts: 1. 10-digit Icom parts numbers 2. Component name 3. Equipment model name

4、and unit name 4. Quantity required 1110003491 S.IC TA31136FNG IC-7700 MAIN UNIT 5 pieces 8820001210 Screw 2438 screw IC-7700 Top cover 10 pieces Addresses are provided on the inside back cover for your convenience. Icom, Icom Inc. and logo are registered trademarks of Icom Incorporated (Japan) in th

5、e United States, the United Kingdom, Germany, France, Spain, Russia and/or other countries. ORDERING PARTS 1. Make sure the 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

6、 variable components. Turn 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 Standard Signal Generator or a

7、Sweep Generator. 7. ALWAYS connect a 50 dB to 60 dB attenuator between the transceiver and a Deviation Meter or Spectrum Analyzer when using such test equipment. 8. READ the instructions of test equipment throughly before connecting a test equipment to the transceiver. REPAIR NOTES INTRODUCTIONCAUTI

8、ON CONTENTS SECTION 1 SPECIFICATIONS SECTION 2 INSIDE VIEWS SECTION 3 CIRCUIT DESCRIPITON 3-1 RECEIVER CIRCUITS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 3-2 TRANSMITTER CIRCUITS . . . . . . . . . . . . . . . . . . . . . . . .

9、. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3 3-3 FREQUENCY SYNTHESIZER CIRCUITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4 3-4 MAIN CPU PORT ALLOCATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10、 3-5 SECTION 4 ADJUSTMENT PROCEDURES 4-1 PREPARATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 4-2 ADJUSTMENTS ON THE OSC UNIT AND PLL UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3 4-3 ADJUST

11、MENTS ON THE RF UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5 4-4 ADJUSTMENTS ON THE PA200W BOARD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7 4-5 ADJUSTMENTS ON THE MAIN UNIT (including RF UNIT). . . . . . . .

12、. . . . . . . . . . . . . . . . . . . 4-9 4-6 ADJUSTMENTS ON THE SCOPE UNIT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11 4-7 AUTOMATIC ADJUSTMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-12 SECTIO

13、N 5 PARTS LIST SECTION 6 MECHANICAL PARTS SECTION 7 BOARD LAYOUTS SECTION 8 GENERAL WIRING SECTION 9 BLOCK DIAGRAM SECTION 10 SCHEMATIC DIAGRAM FRONT UNIT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-1 LOGIC UNIT . .

14、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-2 MAIN UNIT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-8 PLL UNIT. . . . . . . . . . .

15、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-12 OSC UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-13 ANT-SW UNIT . . . . . . . . . . . . .

16、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-16 DIGISEL UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-16 RF UNIT. . . . . . . . . . . . . . . . . . . . . . .

17、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-17 NETWORK BOARD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-22 CTRL BOARD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

18、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-23 FILTER UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-24 PA200W BOARD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

19、 . . . . . . . . . . . . . . . . . . . . . . . 10-25 SCOPE UNIT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-26 DC-DC UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

20、. . . . . . . . . . . . . . . . 10-29 1 - 1 SECTION 1 SPECIFICATIONS DD General Frequency coverage (unit: MHz): Receiver0.03000060.000000*1 Transmitter1.8000001.999999*2, 3.5000003.999999*2, 5.330500*3, 5.346500*3, 5.366500*3, 5.371500*3, 5.403500*3, 7.0000007.300000*2, 10.10000010.150000*2, 14.0000

21、0014.350000*2, 18.06800018.168000*2, 21.00000021.450000*2, 24.89000024.990000*2, 28.00000029.700000*2, 50.00000054.000000*2 *1Some frequency ranges are not guaranteed. *2Depending on versions.*3USA version only. Operating mode: USB, LSB, CW, RTTY, PSK31, AM, FM Number of memory channels: 101 (99 reg

22、ular, 2 scan edges) Antenna connector: SO-2394 (antenna impedance: 50 ?) Operating temperature range: 0C to +50C; +32F to +122F Frequency stability: Less than 0.05 ppm (approx. 5 min. after from turn the main power, I/O, ON, 050C; 32122F) Frequency resolution: 1 Hz Power supply requirement: 85265 V

23、AC (universal input) Power consumption: ReceiveStand-by200 VA typical Max. audio210 VA typical Transmitat 200 W800 VA Dimensions (projections not included): 425149437 mm; 16233257817732in Weight: Approx. 22.5 kg; 50 lb ACC 1 connectors: 8-pin DIN connector ACC 2 connectors: 7-pin DIN connector Displ

24、ay*: 7-inch(diagonal)TFT color LCD (800480) EXT-DISPLAY connector: D-sub 15S CI-V connector: 2-conductor 3.5 (d) mm (18?) RS-232C connector: D-sub 9-pin USB connector: USB (Universal Serial Bus)1.1/2.02 DD Transmitter Transmit output power: SSB, CW, RTTY, PSK31, FM5200 W AM550 W Modulation system: S

25、SBD.P.S.N. modulation AMDigital low power modulation FMDigital phase modulation Spurious emission: HarmonicsMore than 60 dB (HF bands) More than 70 dB (50 MHz band) Unwanted emissionMore than 50 dB (HF bands) (except Harmonics)More than 66 dB (50 MHz band) Out of band emissionMore than 40 dB (HF ban

26、ds) More than 60 dB (50 MHz band) Carrier suppression: More than 63 dB Unwanted side-band suppression: More than 80 dB TX variable range: 9.999 kHz Microphone connector: 8-pin connector (600 ?) ELEC-KEY connector: 3-conductor 6.35 (d) mm (14?) KEY connector: 3-conductor 6.35 (d) mm (14?) RELAY conne

27、ctor: Phono (RCA) ALC connector: Phono (RCA) 1 - 2 DD Receiver Receive system: Double conversion superheterodyne system Intermediate frequencies: 1st64.455 MHz 2nd36 kHz Sensitivity (typical): SSB, CW, RTTY (BW=2.4 kHz, 10 dB S/N) 0.100000 1.799999 MHz0.5 V (pre-amp 1 ON) 1.80000029.990000 MHz0.16 V

28、 (pre-amp 1 ON) 50.00000054.000000 MHz0.13 V (pre-amp 2 ON) AM (BW=6 kHz, 10 dB S/N) 0.100000 1.799999 MHz6.3 V (pre-amp 1 ON) 1.80000029.990000 MHz2 V (pre-amp 1 ON) 50.00000054.000000 MHz1 V (pre-amp 2 ON) FM (BW=15 kHz, 12 dB SINAD) 28.00000029.990000 MHz0.5 V (pre-amp 1 ON) 50.00000054.000000 MH

29、z0.32 V (pre-amp 2 ON) Internal Modulate Distortion (typical): Dynamic range 109 dB (at 14.100 MHz, 100 kHz separation, pre-amp OFF, CW mode; BW=500 Hz) Selectivity: SSB, RTTY (BW=2.4 kHz)More than 2.4 kHz/3 dB Less than 3.6 kHz/60 dB CW (BW=500 Hz)More than 500 Hz/3 dB Less than 700 Hz/60 dB AM (BW

30、=6 kHz)More than 6.0 kHz/3 dB Less than 15.0 kHz/60 dB FM (BW=15 kHz)More than 12.0 kHz/6 dB Less than 20.0 kHz/60 dB Spurious and image rejection ratio: More than 70 dB Squelch sensitivity (pre-amp OFF): SSB, CW, RTTY, PSK31Less than 5.6 V FMLess than 1 V RIT variable range: 9.999 kHz Audio output

31、power: More than 2.6 W at 10% distortion with an 8 ? load PHONES connector: 3-conductor 6.35 (d) mm (14?) EXT-SP connectors: 2-conductor 3.5 (d) mm (18?)/8 ? DD Antenna tuner Matching impedance range: 16.7 to 150 ? unbalanced (HF bands; VSWR better than 3:1) 20 to 125 ? unbalanced (50 MHz band; VSWR

32、 better than 2.5:1) Minimum operating input: 8 W (HF bands) 15 W (50 MHz band) Tuning accuracy: VSWR 1.5:1 or less Insertion loss (after tuning) : Less than 1.0 dB All stated specifications are typical and subject to change without notice or obligation. 2 - 1 SECTION 2 INSIDE VIEW (viewing from the

33、bottom) RF UNIT OSC UNIT DIGISEL UNIT (under the cover) MAIN UNIT PLL UNIT SCOPE UNIT 3 - 1 SECTION 3 CIRCUIT DESCRIPTION 3-1 RECEIVER CIRCUITS ANT-SW UNIT Antenna switching relays (RL51, 61, 71, 81) select the RX signals which are from ANT1ANT4, and the relays are controlled by relay controller (IC

34、11). RX signals from ANT1 ANT3 are applied to the CTRL BOARD, RX signals from ANT4 are applied to the RF UNIT directly. CTRL BOARD The CTRL BOARD has TX/RX switch which toggles the RF path between in TX and RX. RX signals from the ANT-SW UNIT are passed through the TX/RX switches (RL252254), and app

35、lied to the RF UNIT. RF UNIT RF UNIT contains receive circuits; from RX BPF to 2nd RX IF AMP. The RX signals are filtered by BPFs to remove unwanted signals and amplified, then down-converted twice into 2nd IF signal. The received signals from the ANT-SW UNIT and CTRL BOARD are passed through some r

36、elays and attenuators, then filtered by BPFs which is assigned to filter the RX signals that desired to receive. The filtered RX signals are amplified by RF AMPs before being applied to the 1st mixer. 0.0330 MHz SIGNALS The RX signals from the band SW (RL351) are passed though one of the BPF or LPF.

37、 The filtered signals are entered to the DIGISEL UNIT, and gone through or by-passed the DIGISEL (Digital RF Selector Switch) filter. When the DIGISEL function is activated, the RX signals are passed through the DIGISEL SW (RL21) and narrow bandwidth filter (D_SEL) which filters out unwanted signals

38、 with its sharpen frequency response. The filtered signals are amplified by the RF AMP (Q201) which recovers the insert loss of the D_SEL filter, then backed to the RF UNIT via DIGISEL SW (RL2). The RX signals from the DIGISEL UNIT are applied to or by-passed the Pre-AMP. When the Pre-AMP1/2 is acti

39、vated, the RX signals are applied to the Pre-AMP1 (for all HF bands) or Pre-AMP2 (for 24 MHz and above) via P.AMP SW (RL1004), and the amplified RX signals are applied to the 1st mixer (IC1051) via the P.AMP SWs (RL1005, 1006) and LPF. The RX signals are mixed with the 1st LO signals from the PLL UN

40、IT (1st LO signals are gone through LO AMPs (Q1105, 1104, 1101) before being applied.) to be converted into the 1st RX IF signal. 3060 MHz SIGNALS RX signals from the band SW (RL351) are passed though one of the BPFs (Fc=5054 MHz or Fc=5460 MHz) to remove unwanted signals. The filtered signals are a

41、mplified by one of (or both of) the Pre-AMPs (or by-passed; according to the setting). The amplified RX signals are then applied to the 1st mixer (Q1211, 1212) via the LPF. The RX signals are mixed with the 1st LO signals from PLL UNIT (the 1st LO signals are gone through LO AMP (Q1301), HPF and LPF

42、 before being applied.) to be converted into the 1st RX IF signal. A portion of 1st IF signal is applied to the SCOPE UNIT via buffer (Q1352). The converted 1st RX IF signal is then filtered by one of 1st IF filters on the MCF BOARDs (FI1401). Selecting of the filter to pass is carried out by IF SW

43、(IC1402, 1403). The filtered 1st RX IF signal is amplified by two 1st IF AMPs (Q14011403), then splitted into two before being applied to the 2nd mixers; as a image rejection mixer (IC501, 1502). Each divided 1st RX IF signal is mixed with 2nd LO signals from the PLL UNIT (gone through ATT, LO AMP (

44、Q1651), buffer (IC1651) and another buffer (IC1651), to be converted into the 36 kHz 2nd RX IF signal. One of the LO signal is 90 degrees phase-shifted before being applied to the 2nd mixer (IC1502), and the converted 2nd RX IF is 90 degrees phase-shifted too. These converted 2nd RX IF signals are b

45、uffer-amplified by buffer (IC1502/IC1501) and amplified by 2nd IF AMP (IC1504/IC1503). Then the 2nd RX IF signals whose phase is different each other are phase-shifted by the phase shifter (IC1505), then composed by the composer (IC1505). The composed 2nd RX IF signal is amplified by another 2nd IF

46、AMP (IC1506), then entered to the MAIN UNIT. SignalFrequencySignalFrequency 1st RX IF64.455 MHz1st RX LO64.485124.455 MHz 2nd RX IF36 kHz2nd RX LO64.491 MHz 1st TX IF36 kHz1st TX LO64.485124.455 MHz 2nd TX IF455 kHz2nd TX LO64 MHz 3rd TX IF(*) *; Refer to SPECIFICATIONS. FREQUENCY CONFIGURATION 3 -

47、2 MAIN UNIT MIAN UNIT contains receive circuits; from demodulator to AF circuits. The 2nd IF signal is demodulated by digital audio processing circuits. DEMODULATOR CIRCUIT The 36 kHz 2nd RX IF signal from the MAIN UNIT is applied to the Analog to Digital Converter (ADC; IC1251) via the IF mute SW (

48、IC1201) and unbalance-balance convert circuit (IC1211, 1231), to be converted into the 24-bit serial data. The serial data is applied to the DSP (IC1001) and processed as digital audio signals. The processed digital audio signals are then applied to the Digital Audio Converter (DAC; IC1501) to be co

49、nverted into the analog audio signals; as recovered AF signals. The recovered AF signals are applied to the RX AF circuits via buffer (IC1751). RX AF CIRCUITS The recovered AF signals are amplified and level-adjusted, then output from the audio interfaces. (The destination of AF output signals is depends on the setting) The recovered AF signals from the buffer (IC1751) are passed through the SQL SW (Q351), and applied to the AF AMP (IC331). The amplified AF signals are splitted into two AF lines;