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SERVICE
MANUAL
MF/HF MARINE TRANSCEIVER
iM802
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INTRODUCTION DANGER This service manual describes the latest service information NEVER connect the transceiver to an AC outlet or to a DC for the IC-M802 MF/HF MARINE TRANSCEIVER at the time power supply that uses more than 16 V. This will ruin the transceiver. of publication. DO NOT expose the transceiver to rain, snow or any liquids. MODEL VERSION SYMBOL DO NOT reverse the polarities of the power supply when con- U.S.A. USA necting the transceiver. Canada CAN IC-M802 DO NOT apply an RF signa
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TABLE OF CONTENTS SECTION 1 SPECIFICATIONS SECTION 2 INSIDE VIEWS SECTION 3 CIRCUIT DESCRIPTION SECTION 4 ADJUSTMENT PROCEDURES SECTION 5 PARTS LIST SECTION 6 MECHANICAL PARTS AND DISASSEMBLY 6 - 1 RC-25....................................................................................................................................................... 6 - 1 6 - 2 SP-24 .............................................................................................................................
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SECTION 1 SPECIFICATIONS • IC-M802 ‘ ‘ GENERAL • Frequency coverage : 500 kHz–29.9999 MHz Receive 1.6000–2.9999 MHz 4.0000–4.9999 MHz 6.0000–6.9999 MHz 8.0000–8.9999 MHz 12.0000–13.9999 MHz 16.0000–17.9999 MHz Transmit 18.0000–19.9999 MHz 22.0000–22.9999 MHz 25.0000–27.5000 MHz 2.1875 MHz, 4.2075 MHz, 6.3120 MHz, 8.4145 MHz, DSC receive 12.5770 MHz, 16.8045 MHz [USA], [CAN] • Mode : TX/RX J3E (USB/LSB), J2B (AFSK), F1B (FSK), A1A (CW) H3E [OTH] RX H3E [USA], [CAN] DSC J2B [USA], [CAN] • Antenn
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• RC-25 Remote controller ‘ ‘ GENERAL • Microphone impedance : 600 Ω • Audio output power : More than 5 mW at 16 Ω headphone with 10 % distortion • Audio output impedance : 8–16 Ω • Usable temperature range : –20˚C to +55˚C; –4˚F to +131˚F • Dimension (projections not included) : 220(W) × 110(H) × 84.4(D) mm; 8 21⁄32(W) × 4 11⁄32(H) × 3 5⁄16(D) in. • Weight : 570 g; 1.3 lb; 20.1 oz • SP-24 External speaker ‘ ‘ GENERAL • Impedance : 4 Ω • Input power : Rated input; 5 W Maximum input; 7 W • Usable
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SECTION 2 INSIDE VIEWS • RC-25 VR BO VR BOARD ARD Reset IC Reset IC (IC8202: (IC8202: S-80942ANMP) S-80942CNMC) CPU CPU DISPLA DISPLAY BO Y BOARD ARD (IC8201: (IC8201: HD64F2134AF HD64F2134AFA20) A20) LCD unit LCD unit (DS8220: (DS8220: HLC770-018800) HLC7700-018800) SENSOR BO SENSOR BOARD ARD P Po ow wer amplifier er amplifier (IC8270: (IC8270: T TA7368F) A7368F) • IC-M802 DSC 1st mixer D2301: HSB88WS [USA],[CAN] only DSC 2nd mixer IC2701: TA4107F PA UNIT [USA],[CAN] only MAIN UNIT MAIN UN
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SECTION 3 CIRCUIT DESCRIPTION The IF amplifier (Q203) and resonator circuits are designed 3-1 RECEIVER CIRCUITS between the filter pair. The PLL output signal (1LO) enters 3-1-1 RF FILTER CIRCUIT (FILTER AND MAIN the MAIN unit via the J601 and is amplified at the 1st LO UNITS) amplifier (Q601). The amplified signal is passed through the Received signals from the antenna connector are applied to 100 MHz cut-off low-pass filter (L604, L605, C604, the transmit/receive switching and protection relay
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The level-shifted signal is applied to the DSP IC (IC301) for When receiving strong signals, the detected voltage increas- the digital IF filter, demodulator, automatic notch and noise es and the AGC1 voltage decreases. As the AGC1 voltage reduction, etc. is used for the bias voltage of the IF amplifiers (MAIN unit; Q203, Q401, Q501), IF amplifier gain is decreased. The output signal from the DSP IC is applied to the D/A con- verter section in the CODEC IC (IC501) to convert into the analog audi
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When the speech compressor function is ON, the level-shift- 3-2 TRANSMITTER CIRCUITS ed signal from the CODEC IC (IC501) is applied to the DSP 3-2-1 MICROPHONE AMPLIFIER CIRCUIT IC (IC301) and compressed at the DSP IC to obtain an aver- (RC-25, MAIN AND DSP UNITS) age audio level. The microphone amplifier circuit amplifies microphone audio signal to a level needed for the DSP circuit. At the same time, the compressed signals are modulated at the DSP IC and applied to the D/A converter section i
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3-2-5 RF CIRCUIT (MAIN, PA UNITS AND DRIVER • 2–2.9999 MHz signal The signal is applied to the relay (FILTER unit; RL7061) BOARD) which is controlled by the band control IC (MAIN unit; The RF circuit amplifies operating (transmitting) frequency IC3602) as the “L2M” signal via the buffer amplifier (MAIN to obtain 150 W of RF output. unit; IC1301, pin 12). The signal passes through the low- pass filter (FILTER unit; L7066–L7068, C7063–C7084, The signal from the 1st IF mixer is passed through one o
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• 14–19.9999 MHz signal • SWR APC CIRCUIT (FILTER AND MAIN UNITS) The signal is applied to the relay (FILTER unit; RL7211) The reflected wave signal appears and increases on the which is controlled by the band control IC (MAIN unit; antenna connector. When the antenna is mismatched, IC3602) as the “L16M” signal via the buffer amplifier (MAIN D7272 of the power detector circuit (D7271, D7272, L7272) unit; IC1301, pin 17). The signal passes through the low- in the FILTER unit detects the signal an
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The detected signal output from the PLL IC (pin 2) is con- 3-3 PLL CIRCUITS verted into a DC voltage (lock voltage) at the loop filter and 3-3-1 GENERAL then fed back to one of the VCO circuits (Q5521, D5521, The PLL circuits generate a reference frequency (32.000 L5523). MHz); 1st LO frequencies (64.485–94.455 MHz); 2nd LO frequency (64 MHz), 3rd LO frequency (433.000 kHz). The oscillated signal from the buffer amplifier (Q5601) is also applied to the MAIN unit as a 1st LO signal after being Th
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The 1st IF signal from the 1st IF amplifiers is applied to the 3-4 DSC CIRCUITS ([USA], [CAN] ONLY) 2nd mixer IC (IC2701, pin 3), and is mixed with the 2nd LO 3-4-1 DSC BANDPASS FILTER AND RF AMPLIFIER signal to the converted into a 12 kHz 2nd IF signal. CIRCUITS (MAIN UNIT) The RF circuit filters out-of-band signals and amplifiers sig- The 12 kHz 2nd IF signal from the 2nd mixer (IC2701, pin 5) nals within the range of frequency coverage. is applied to the 2nd IF amplifier (IC2702, pin 3), and
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3-6-3 PLL UNIT VOLTAGE LINE 3-5-3 GROUP AND CHANNEL DIALS CIRCUIT (DISPLAY AND SENSOR BOARDS) LINE DESCRIPTION • GROUP DIAL The signals from the group dial (SENSOR board; S8801) is HV13 The voltage from PA and MAIN units via the applied to the FRONT CPU (IC8201, pins 76, 77) via the J5001. “GPA” and “GPB” signals. H5V Common 5 V line from the MAIN unit via the J5071. • CHANNEL DIAL The signals from the channel dial (SENSOR board; S8802) 5V Common 5 V converted from the 13 V line and is applied t
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3-7 PORT ALLOCATIONS MAIN CPU (MAIN UNIT; IC3303)–continued 3-7-1 MAIN CPU (MAIN UNIT; IC3303) Pin Port Pin Port Description Description number name number name Outputs T8 regulator circuit (MAIN Outputs serial clock signal for the 1 TXS 90 ECK unit; Q1501) control signal. EEPROM (IC3301, pin 6). Outputs R8 regulator circuit (MAIN Input port for the SEND signal from 2 RXS 92 ASEN unit; Q1502) control signal. the accessory connector (J1801). Outputs serial strobe signal to the Input port for the
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3-7-4 OUTPUT EXPANDER IC FOR BANDPASS FIL- 3-7-7 D/A CONVERTER IC (IC3606) TERS (IC3604) Pin Port Description Pin Port number name Description number name Outputs transmit power control signal. Outputs 0.5–1.999999 MHz bandpass The signal is applied to the ALC ampli- 4 B0S 5 POCV filter control signal. fier (IC1201, pin 3) and RF amplifier (Q701). Outputs 2–2.999999 MHz bandpass 5 B1S filter control signal. Outputs the VCA control signal. The signal is applied to the VCA amplifier Outputs 3–4.99
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3-7-8 FRONTCPU PORT ALLOCATIONS (RC-25, DISPLAY BOARD; IC8201) Pin Port Description number name Outputs DISTRESS LED control sig- 17 DSEL nal. 21 FUNK Input port for the O switch. 22 TXK Input port for the [TX] switch. 23 RXK Input port for the [RX] switch. 24 FCHK Input port for the [FREQ/CH] switch. 25 T0K Input port for the [0] switch. 26 ENTK Input port for the [ENT] switch. 28 PWRK Input port for the [POWER] switch. Input port for the phone plug insert 31 PMUT detection signal. Input port f
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SECTION 4 ADJUSTMENT PROCEDURES 4-1 PREPARATION When adjusting the contents on page 4-9, a JIG CABLE (see illustration as shown below) is required. Some adjustments must be performed on the “ADJUSTMENT MODE”. Entering the “ADJUSTMENT MODE”, see the next page. REQUIRED TEST EQUIPMENT EQUIPMENT GRADE AND RANGE EQUIPMENT GRADE AND RANGE Output voltage : 13.6 V DC Frequency range : 300–3000 Hz DC power supply Audio generator Current capacity : 30 A or more Output level : 1–500 mV Measuring range :
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ENTERING THE ADJUSTMENT MODE 1 Turn the power OFF. 2 Push and hold the HM-135’s [DOWN] key, [TX] and [RX] buttons, then turn the power ON. NOTE: Inserting the 15 kΩ resistor between 2 pin and 6 pin of HM-135 works same as pushing and holding HM-135’s [DOWN] key (See the illustration on page 4-1). [TX] [RX] [DOWN] key [POWER] Connect to [MIC] connector. OPERATING ON THE ADJUSTMENT MODE • Enter the TX adjustment from the MAIN menu. : Push the [1] button • Enter the RX adjustment from the MAIN
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4-2 PLL UNIT ADJUSTMENT MEASUREMENT ADJUSTMENT ADJUSTMENT ADJUSTMENT CONDITIONS VALUE UNIT LOCATION UNIT ADJUST LPL LOCK 1 • Operating frequency : 0.5000 MHz PLL Connect a digital multi 1.0 V PLL C5305 VOLTAGE • Mode : J3E meter or oscilloscope • Receiving to check point CP5301. 2 • Operating frequency : 0.4999 MHz Less than 4.0 V Verify • Receiving HPL LOCK 1 • Operating frequency : 29.9999 MHz PLL Connect a digital multi 4.2 V PLL C5521 VOLTAGE • Mode : J3E meter or oscilloscope • Receiving to
