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11 - 1

 

SECTION 11 

VOLTAGE DIAGRAM

3 . 3 1 V

R : 6 . 8 5 V

DIM MAX:12.27V

0V

0 . 4 6 V

7.9872MHz

DS

7

RY-SP110UHY24

27

R23

S-80942CNMC

IC5

1

OUT

2

VDD

3

VSS

4

NC

5

CD

J2

B4B-ZR-SM4-TF

1
2
3
4

5

6

12K

R27

39K

R24

470P

C44

10K

R3

DTRS

S7

UP

S5

1M

R65

10K

R42

10K

R62

47K

R15

KDS122

D3

5.6K

R1

NJM2

904M

IC

6

1

2

3

4

5

6

7

8

150K

R14

24P

C31

KTA1664

Q2

0

R67

390

R31

0.01

C11

100K

R51

3.3K

R28

M37560EFGP

IC1

1

P67/AN7

2

P66/AN6

3

P65/AN5

4

P64/AN4

5

P63/SCLK22/AN3

6

P62/SCLK21/AN2

7

P61/SOUT2/AN1

8

P60/SIN2/AN0

9

P57/ADT/DA2

10

P56/DA1

11

P55/CNTR1

12

P54/CNTR0

13

P53/RTP1

14

P52/RTP0

15

P51/PWM1

16

P50/PWM0

17

P47/SRDY1

18

P46/SCLK 1

19

P45/TXD

20

P44/RXD

21

P43/TOUR

22

P42/INT2

23

P41/INT1

24

P40

25

P77

26

P76

27

P75

28

P74

29

P73

30

P72

31

P71

32

P70/INT0

33

RESET

34

XCI

N

35

XCOUT

36

XIN

37

XOUT

38

VSS

39

P27

40

P26

41

P25

42

P24

43

P23

44

P22

45

P21

46

P20

47

P17

48

P16

49

P15/SEG39

50

P14/SEG38

51

P13/SEG37

52

P12/SEG36

53

P11/SEG35

54

P10/SEG34

55

P07/SEG33

56

P06/SEG32

57

P05/SEG31

58

P04/SEG30

59

P03/SEG29

60

P02/SEG28

61

P01/SEG27

62

P00/SEG26

63

P37/SEG25

64

P36/SEG24

65

P35/SEG23

66

P34/SEG22

67

P33/SEG21

68

P32/SEG20

69

P31/SEG19

70

P30/SEG18

71

SEG17

72

SEG16

73

SEG15

74

SEG14

75

SEG13

76

SEG12

77

SEG11

78

SEG10

79

SEG9

80

SEG8

81

SEG7

82

SEG6

83

SEG5

84

SEG4

85

SEG3

86

SEG2

87

SEG1

88

SEG0

89

VCC

90

VREF

91

AVSS

92

COM3

93

COM2

94

COM1

95

COM0

96

VL3

97

VL2

98

C2

99

C1

100

VL1

0.47

C21

30FLT-SM2-TB

J1

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

470P

C4

470P

C2

KTC4075

Q3

0.001

C26

10K

R16

0.

1

C6

DN

S4

470P

C41

DS

4

SML-311YT

0.01

C25

0.001

C14

DS

6

RY-SP110UHY24

0.001

C12

47K

R25

CP1

CP10S

CP10S

CP7

10K

R4

150

R40

10K

R56

6.8K

R54

22

C22

CP4

CP10S

1SS355

D2

0.0047

C16

DTC114TU

Q6

10K

R64

27

R21

1K

R29

15K

R37

100K

R61

0.01

C3

KTC4075

Q4

CH1 6

S3

10K

R5

TC7S14FU

IC3

1
2
3

4

5

27

R22

CP10S

CP6

HN58X2464TI

IC4

1

A0

2

A1

3

A2

4

VSS

5

SDA

6

SCL

7

WP

8

VCC

CH/WX

S2

220

R35

0.01

C5

1SS355

D1

0.001

C43

CR-834

X1

SML-311YT

DS

3

0.01

C17

470P

C42

1K

R38

6.8K

R36

0.01

C1

DSC

S6

1M

R52

SCAN

S1

0.027

C23

DS

5

SML-311YT

0.01

C7

BE

CP3

10K

R43

10K

R63

22P

C32

1K

R30

10K

R41

0.01

C18

SDT-DM2360

DS1

1

S27

2

S28

3

S13

4

S14

5

S15

6

S16

7

S17

8

S18

9

S19

10

S20

11

S21

12

S22

13

S23

14

S24

15

S25

16

S26

17

C0

18

C1

19

C2

20

C3

21

S1

22

S2

23

S3

24

S4

25

S5

26

S6

27

S7

28

S10

29

S11

30

S8

31

S9

32

S12

CP10S

CP5

SML-311YT

DS

2

CP2

CP10S

PC357N6J000F

IC2

0.01

C13

1K

R26

10K

R55

10K

R53

TXDET
SQLV

PCK
PDATA
WXDEC

BEEP
PSTB

DSCDEC
UNLK

SEG6

SEG18
SEG19
SEG20

SEG3

SEG21
SEG22
SEG23

SEG2

SEG24
SEG25
SEG26

SEG1

SEG12

TMUTE

SEND

RCV

BPLV L

RMUTE

H/ L

SQLC

PTTC

KEYM

PTT

SQ

L

BPF

SEG27

SEG28

SEG13

SEG14

SEG15

SEG16

SEG17

SEG18

SEG19

SEG20

SEG21

SEG22

SEG23

SEG24

SEG25

SEG26

SEG12

SEG9

SEG8

SEG11

SEG10

SEG7

SEG6

SEG5

SEG4

SEG3

SEG2

SEG1

COM3

COM2

COM1

COM0

SEG27

BEE P

TMUTE
TXDET
H/ L
PSTB
PDATA

WXDEC
DSCDEC
RCV
SEND

BPLVL

DSCENC

RMUTE

PTTC

PTT

KEYM

SQL

SQLC

BPF

PCK

UNLK

GND

COM0

COM1

COM2

COM3

SEG4

SEG5

SEG8

SEG9

SEG10

SEG11

SEG28

SEG13

SEG14

SEG7

SEG15

SEG16

SEG17

SQLV

DSCENC

5V

5V

5V

HVS

NMEA+
NMEA-

ICF3

SP-

SP+

HVS

5V

ICF3

R1

10k

J1

To W1 (MAIN UNIT)

To W1 (MAIN UNIT)

1

2

3

4

5

VOL1

VOL2

GND

HV

HVS

R1

10k

J1

1

2

3

GND
SQLV
SQLI

• LOGIC UNIT

• VR UNIT

• SQL UNIT

Summary of Contents for IC-M304

Page 1: ...S 14311XZ C1 Dec 2006 VHF MARINE TRANSCEIVER iC m304 ...

Page 2: ...FNG IC M304 MAIN UNIT 5 pieces 8820001210 Screw 2438 screw IC M304 CHASSIS 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 the United States the United Kingdom Germany France Spain Russia and or other countries ORDERING PARTS 1 Make sure a problem is internal before disassembling the trans...

Page 3: ...OWER SUPPLY CIRCUITS 4 4 4 7 PORT ALLOCATIONS 4 5 SECTION 5 ADJUSTMENT PROCEDURES 5 1 PREPARATION 5 1 5 2 FREQUENCY ADJUSTMENT 5 2 5 3 TRANSMIT ADJUSTMENT 5 3 5 4 RECEIVE ADJUSTMENT 5 4 SECTION 6 PARTS LIST SECTION 7 MECHANICAL PARTS AND DISASSEMBLY SECTION 8 SEMICONDUCTOR INFORMATION SECTION 9 BOARD LAYOUTS SECTION 10 BLOCK DIAGRAM SECTION 11 VOLTAGE DIAGRAM 11 1 LOGIC UNIT Incl SQL and VR UNITs ...

Page 4: ...5 W Less than 56 dBc at 1 W Adjacent channel power More than 70 dB Audio harmonic distortion Less than 10 at 60 deviation Residual modulation More than 40 dB Audio frequency response 1 dB to 3 dB of 6 dB oct from 300 Hz to 2500 Hz Microphone impedance 2 kΩ M RECEIVER Receive system Double conversion superheterodyne system Intermediate frequencies 1st IF 21 7 MHz 2nd IF 450 kHz Sensitivity 13 dBµ t...

Page 5: ...1 6 5 1 A 2 6 5 7 7 0 6 1 5 7 1 6 5 1 3 6 5 7 1 6 5 1 5 7 1 6 5 1 A 3 6 5 2 8 0 6 1 5 2 2 6 5 1 4 6 4 6 5 2 2 6 5 1 5 2 2 6 5 1 A 4 6 A 4 6 5 7 8 0 6 1 5 7 2 6 5 1 5 6 5 7 2 6 5 1 5 7 2 6 5 1 A 5 6 A 5 6 A 5 6 5 2 9 0 6 1 5 2 3 6 5 1 6 6 A 6 6 A 6 6 1 5 2 3 6 5 1 5 2 3 6 5 1 A 6 6 7 6 2 5 7 3 6 5 1 5 7 3 6 5 1 7 6 7 6 0 5 0 7 5 1 0 5 0 7 5 1 A 1 2 A 1 2 A S U 0 5 6 1 6 1 0 5 0 7 5 1 1 2 1 2 N A C ...

Page 6: ...er FI3 LT450EW DSC DECODER IC3 NJM2211M IDC LPF IC10 NJM4558M MIC MUTE SWITCH IC7 TC7W66EU 1st IF filters FI1 FL 368 FI2 FL 399A IF IC IC1 TA31136FN PLL IC IC8 uPD3140GS VCO DIMMER CONTROL CIRCUIT Q2 KTA1664 Q3 Q4 KTC4075 CPU IC1 M37560EFGP EEPROM IC4 HN58X2464T1 TONE BUFFER IC6 NJM2904M ...

Page 7: ...aker cable F 2 points and DC cable G 2 points on the bottom side of the MAIN UNIT w Unsolder the antenna connector B 3 points e Remove the clip C r Unscrew 2 screws D and 7 screws E to remove the MAIN UNIT 3 Removing the LOGIC UNIT q Disconnect 2 cables I and K w Unsolder 2 points H e Unscrew 4 screws J to remove the LOGIC UNIT A A A RONT ANEL CASE E C E B D G F speaker MAIN UNIT DC cable I J K H ...

Page 8: ...n ratio and obtains stable receiver gain The FM IF IC IC1 contains the 2nd local oscillator 2nd mixer limiter amplifier quadrature detector and noise detector circuits etc The 1st IF signal from Q4 is applied to the 2nd mixer section of IC1 pin 16 and is mixed with a 21 25 MHz 2nd LO signal generated at the PLL circuit using the reference frequency 21 25 MHz to produce a 450 kHz 2nd IF signal The ...

Page 9: ... has amplification output capabilities of about 25 W with 10 mW input The output from IC4 pin 4 is passed through the antenna switching circuit D1 and is then applied to the antenna connector via the low pass filter 4 1 5 AF AMPLIFIER CIRCUIT MAIN AND FRONT UNITS The AF amplifier circuit amplifies the detected signals to drive a speaker The AF circuit includes an AF mute circuit for the squelch AF...

Page 10: ...the loop filter R211 R213 C252 C254 and is then applied to varactor diodes D13 D14 of the VCO to stabilize the oscillated frequency 4 3 4 VCO CIRCUIT MAIN UNIT The VCO outputs from Q13 Q14 are buffer amplified at the buffer amplifiers Q15 and Q16 and are then sent to the Tx Rx switch D16 and D17 The receive LO signal is applied to the 1st mixer circuit Q2 through a low pass filter and the transmit...

Page 11: ...1 RESET CIRCUIT IC5 which is a reset IC outputs a reset signal HIGH pulse signal to the CPU IC1 pin 33 from pin 1 when the transceiver turns power ON LOW BATTERY DETECTOR HVS voltage is divided by R14 and R15 and is applied to the low battery detector section in the CPU IC1 pin 1 DIMMER CIRCUIT CPU IC1 Q2 Q3 and Q4 compose dimmer circuit The circuit controls 4 steps LCD backlight DS2 DS7 UART PORT...

Page 12: ... to the attenuator D22 High Attenuator ON 57 PTT Input port for the PTT switch HM 150B SW S1 Low PTT key is pushed 60 UNLK Input port for the UNLK signal from the PLL IC IC1 pin7 High PLL circuit is unlocked Pin NO Port name Description 61 DTRS Input port for the DISTRESS key LOGIC BOARD S9 Low DISTRESS key is pushed 62 RMUTEP Outputs AF Public Address mute signal to the AF mute circuit IC4 pin12 ...

Page 13: ...or better Sensitivity 100 mV or better AC millivoltmeter Measuring range 10 mV to 10 V FM deviation meter Frequency range 30 300 MHz Measuring range 0 to 10 kHz External speaker Input impedance 4 Ω Capacity More than 5 W Audio generator Frequency range 300 3000 Hz Output level 1 500 mV Attenuator Power attenuation 40 dB Capacity More than 30 W 5 1 PREPARATION CONNECTIONS FM IC M304 deviation meter...

Page 14: ...Output power Low Connect a power meter to the ant enna connector Transmitting 1 4 2 4 V Verify REFERENCE FREQUENCY 1 Channel CH16 156 800 MHz Output power Low Connect a power meter to the ant enna connector Transmitting 1 Loosely couple a frequency counter to the ant enna connector 2 Adjust C257 REF 156 800 MHz ADJUST CHECK POINTS LOCATION FREQUENCY LV LOCK VOLTAGE CHECK POINT C57 REF RECEIVE SENS...

Page 15: ...ower Low Connect an audio generator to the MIC line see the picture below and set as Frequency 1 kHz Level 140 mV Connect an FM deviation meter to the ant enna connector through an attenuator and set as HPF OFF LPF 20 kHz De emphasis OFF Detector P P 2 Transmitting Adjust R184 DEV 4 3 kHz ADJUST CHECK POINTS LOCATION TRANSMIT KEYM GND MIC MICG PTT 1 5 AC millivoltmeter Audio generator PTT J2 R135 ...

Page 16: ... and set as Frequency 156 800 MHz Level 0 dBu 107 dBm Modulation 1 kHz Deviation 3 0 kHz Receiving 1 Connect a DC voltmeter to the check point RSSI 2 Adjust in sequence L6 L7 L8 and L9 Repeate the adjustment at least twice Maximum voltage ADJUST CHECK POINTS LOCATION RECEIVE L6 L7 L8 L9 RSSI RECEIVE SENSITIVITY CHECK POINT RECEIVE SENSITIVITY ADJUSTMENT POINTS The output level of the standard sign...

Page 17: ... 32 7 C23 4030008890 S CER C1608 JB 1H 273K T B 30 44 5 C25 4030006900 S CER C1608 JB 1H 103K T B 25 2 42 1 C26 4030006860 S CER C1608 JB 1H 102K T B 29 14 C31 4030009650 S CER C1608 CH 1H 240J T B 43 5 40 1 C32 4030007050 S CER C1608 CH 1H 220J T B 42 1 41 1 C41 4030006850 S CER C1608 JB 1H 471K T B 9 6 9 S Surface mount LOGIC UNIT REF ORDER DESCRIPTION M H V NO NO LOCATION C42 4030006850 S CER C...

Page 18: ...3GEYJ 100 V 10 T 48 8 67 4 S Surface mount MAIN UNIT REF ORDER DESCRIPTION M H V NO NO LOCATION R111 7030003560 S RES ERJ3GEYJ 103 V 10 k T 47 64 R112 7030003580 S RES ERJ3GEYJ 153 V 15 k T 49 6 60 2 R113 7030003370 S RES ERJ3GEYJ 271 V 270 T 50 9 64 R126 7030003680 S RES ERJ3GEYJ 104 V 100 k T 57 8 66 4 R127 7030003480 S RES ERJ3GEYJ 222 V 2 2 k T 57 2 68 6 R128 7030003370 S RES ERJ3GEYJ 271 V 27...

Page 19: ... 500V C172 4030006860 S CER C1608 JB 1H 102K T T 69 3 60 3 C173 4030006860 S CER C1608 JB 1H 102K T T 73 5 60 3 C174 4010005430 CER HM60SJ CH 050C 500V C175 4030006860 S CER C1608 JB 1H 102K T T 82 9 52 9 C176 4030006860 S CER C1608 JB 1H 102K T T 63 5 64 5 C177 4030006900 S CER C1608 JB 1H 103K T T 70 9 53 4 C178 4030006860 S CER C1608 JB 1H 102K T T 66 51 3 C179 4030006850 S CER C1608 JB 1H 471K...

Page 20: ...N 312 C Super White 2 8610011640 KNOB N 312 B Gray 2 MP5 8930014280 Speaker net FX 706 1 MP6 8810010021 Screw BTB0 2 6X8NI ZC3 BT 4 MP7 8930052010 2345 SHAFT 1 MP8 8930060481 2685 SPRING 1 1 MP9 8110008990 2989 D COVER 1 MP10 8930060470 2685 SHAFT ANGLE 1 MP11 8930060490 2685 F BUSH PLATE 1 MP12 8930052280 O ring AC 2 MP13 8930055841 2490 EARTH SPRING 1 1 REF ORDER DESCRIPTION QTY NO NO DS1 503000...

Page 21: ...P11 F MP12 F MP12 F MP13 C MP10 C MP19 C MP12 C MP12 C MP12 C MP8 C MAIN UNIT UNiT ABBREVIATIONS C CHASSIS PARTS F FRONT UNIT L LOGIC UNIT M MAIN UNIT VR VR UNIT SQL SQL UNIT VR UNIT SQL UNIT LOGIC UNIT MP6 F EP2 L MP1 L MP3 L DS1 L MP2 L NOTE 1 NOTE 1 NOTE 2 NOTE 2 E F Unit mm inch 153 0 6 1 32 67 0 2 5 8 143 5 5 21 32 51 0 2 42 2 1 21 32 86 3 3 13 32 137 0 5 13 32 133 5 1 4 ...

Page 22: ... KRC404 Marking ND KTA2015Y Marking Z KTC4080 Marking Q TRANSISTERS AND FETs 1SS355 Marking 5D KDS122 Marking C3 1SS321 Marking F9 DSA3A1 Marking green HSM88ASRTR Marking C3 HVC350BTRF Marking B0 KDV214E Marking UO MA2S077 Marking S MA742 Marking M1U DIODES B E C B E C B E C G1 G2 S D B C C E B1 E B2 C1 C2 B E C B E C B E C B E C A C A C C A1 A2 green A C A C A C A C A C ...

Page 23: ... L L10 L12 L13 L21 2 2 L 3 2 L L26 L28 L29 1 3 L 2 3 L 5 3 L 6 3 L 1 P M 3 P M 1 Q Q2 Q4 5 Q Q6 7 Q Q11 2 1 Q 3 1 Q Q14 Q15 Q16 Q17 9 1 Q 0 2 Q 1 2 Q 2 2 Q Q23 Q25 6 2 Q 1 3 Q Q32 3 3 Q Q34 Q35 Q36 4 R 5 R R6 7 R 8 R 9 R 0 1 R R12 4 1 R R16 7 1 R 1 2 R 5 2 R 6 2 R R27 8 2 R 1 3 R R32 3 3 R R34 R35 R36 R37 R38 R39 R41 2 4 R R43 R44 R45 R46 7 4 R 8 4 R 9 4 R R50 1 5 R R52 3 5 R 4 5 R R55 R56 R57 8 5...

Page 24: ...0 V15 V20 V25 V30 V35 V40 V45 V50 LQS B 6660 H0 H5 H10 0V 5V 01V H0 H5 H10 0V 5V 01V 51V P S P S D N G 0 H 5 H 0 1 H 5 1 H 0 2 H 5 2 H 0 3 H 5 3 H 0 4 H 5 4 H 0 5 H 5 5 H 0 6 H 5 6 H 0 7 H 5 7 H 0 8 H 5 8 H 0 9 H 5 9 H 0 0 1 H 5 0 1 H 0 1 1 H V0 V5 V10 V15 V20 V25 V30 V35 V40 V45 V50 V55 V60 V65 V70 V75 V80 MAIN UNIT BOTTOM VIEW LOGIC UNIT BOTTOM VIEW SQL UNIT BOTTOM VIEW VR UNIT BOTTOM VIEW IC4 M...

Page 25: ...A1664 IC4 HN58X2464TI IC5 S 80942CNMC IC2 PC357N6 IC3 TC7S14FU Q6 7 KTC4075x2 IC6 LA4425A I C10A IC10B Q5 KTC4075 IC3 NJM2211M Q13 14 2SC4226x2 Q26 KTC4080 D16 17 Q19 20 KRC404 I C4 S AV35A I F D21 22 Q21 FMW1 D1 D2 D3 KDS122 IC7B TC7W66FU PROTECT CTRL D25 DSA3A1 HVS T5 HV REVERSE CTRL T5 5V CONNECT R5 Q31 KTA2015 R8 R5 Q22 KRC402 SQL UNIT IC6A NJM2904M 2nd LO TC7W66FU IC9 KIA7805API EXT SP I NT S...

Page 26: ... C4 470P C2 KTC4075 Q3 0 001 C26 10K R16 0 1 C6 DN S4 470P C41 DS 4 SML 311YT 0 01 C25 0 001 C14 DS 6 RY SP110UHY24 0 001 C12 47K R25 CP1 CP10S CP10S CP7 10K R4 150 R40 10K R56 6 8K R54 22 C22 CP4 CP10S 1SS355 D2 0 0047 C16 DTC114TU Q6 10K R64 27 R21 1K R29 15K R37 100K R61 0 01 C3 KTC4075 Q4 CH1 6 S3 10K R5 TC7S14FU IC3 1 2 3 4 5 27 R22 CP10S CP6 HN58X2464TI IC4 1 A0 2 A1 3 A2 4 VSS 5 SDA 6 SCL 7...

Page 27: ...A C113 2 2K R127 Q19 KRC404 0 0022 C93 10P C149 47K R170 2SC4226 Q14 FI 2 FL 399A KDV214E D5 0 68 MSVA C252 15K R76 470P C117 18P C259 KIA7805API IC9 I O COM 470 C213 470P C199 Q20 KRC404 220P C73 2 2K R108 0 1 C249 220 R135 47 R71 0 022 C91 72 0N L22 KRC404 Q12 0 001 C217 470K R64 LA 253 L31 470P C297 0 001 47K R84 1M R155 0 022 C90 KTC4075 Q7 0 22 C103 Q22 KRC402 390 R67 330 R215 LT450EW FI3 I O...

Page 28: ...P16 8810010230 Screw BiH M4X8 ZK 1 MP17 8850002000 SPRING WASHER M4 SUS 1 MP19 8810010240 Screw BT B0 2X6NI 2 MP20 8930061700 2715 PTT PLATE 1 S3 MC1 W2 1 C W1 S4 2 C 1 1 2 2 3 3 4 4 5 5 1 R R3 R2 R4 L4 12k 470p 0 022 0 22u 0 22u 6 8k 15k 33k S2 S1 L3 PTT Y Z HI LO PTT MICG MIC GND KEYM W1 CHASSIS UP ON 2 0V DN ON 3 0V HI LO ON 3 8V M Mounted side T Mounted on the Top side B Mounted on the Bottom ...

Page 29: ...ICOMAMERICA COM USTOMER 3ERVICE 0HONE LENWOOD ENTRE IGHWAY ELTA 6 ANADA 0HONE AX 52 HTTP WWW ICOMCANADA COM MAIL INFO ICOMCANADA COM 5NIT ARDEN 2OAD LAYTON 6 USTRALIA 0HONE AX 52 HTTP WWW ICOM NET AU MAIL SALES ICOM NET AU ARRIS 2OAD AST 4AMAKI UCKLAND EW EALAND 0HONE AX 52 HTTP WWW ICOM CO NZ MAIL INQUIRIES ICOM CO NZ 2OOM TH LOOR ONG 3ILVER ANSION O 9ONG ING 2OAD AIDIAN ISTRICT EIJING HINA 0HONE...

Page 30: ...1 1 32 Kamiminami Hirano ku Osaka 547 0003 Japan S 14311XZ C1 2006 Icom Inc ...

Page 31: ...T FRONT LOGIC VR SQL and HM 164B Black U M304 02 FRONT FRONT LOGIC VR SQL and HM 164SW Super White U M304 03 FRONT FRONT LOGIC VR SQL and HM 164G Gray ORDER NO UNIT NAME 0329890102 U M304 01 MAIN MAIN CHASSIS CHASSIS Incl MAIN UNIT HM 164 ORDER NO UNIT NAME Optional product Optional product Optional product HM 164B Black HM 164SW Super White HM 164G Gray ...

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