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Extracted text from Jvc KDG 646 UH Service Manual (Ocr-read)
Page 1
1-2 (No.MA377)
SPECIFICATION
KD-G441/KD-G351
Design and specifications are subject to change without notice.AUDIO AMPLIFIER SECTION
Maximum Power Output Front/Rear 50 W per channel
Continuous Power Output (RMS) Front/Rear 19 W per channel into 4 -„¦ 40 Hz to 20 000 Hz at no
more than 0.8% total harmonic distortion
Load Impedance 4 -„¦ (4 -„¦ to 8 -„¦ allowance)
Tone Control Range Bass ±12 dB at 60 Hz
Middle ±12 dB at 1 kHz
Treble ±12 dB at 10 kHz
Frequency Response 40 Hz to 20 000 Hz
Signal to Noise Ratio 70 dB
Audio Output Level (for KD-G441) Line-Out Level/Impedance 2.5 V/20 k-„¦ load (full scale)
Output Impedance 1 k-„¦
Subwoofer-Out Level/Impedance 2.5 V /20 k-„¦ load (full scale)
Other Terminals AUX (auxiliary) input jack USB input jack Steering wheel remote input (forKD-G441)
TUNER SECTION
Frequency Range FM 87.5 MHz to 108.0 MHz
AM MW: 522 kHz to 1 620 kHz
LW: 144 kHz to 279 kHz
FM Tuner Usable Sensitivity 11.3 dBf (1.0 µV/75 -„¦)
50 dB Quieting Sensitivity 16.3 dBf (1.8 µV/75 -„¦)
Alternate Channel Selectivity (400 kHz) 65 dB
Frequency Response 40 Hz to 15 000 Hz
Stereo Separation 30 dB
MW Tuner Sensitivity/Selectivity 20 µV/35 dB
LW Tuner Sensitivity 50 µV
CD PLAYER SECTION
Type Compact disc player
Signal Detection System Non-contact optical pickup (semiconductor laser)
Number of Channels 2 channels (stereo)
Frequency Response 5 Hz to 20 000 Hz
Dynamic Range 96 dB
Signal-to-Noise Ratio 98 dB
Wow and Flutter Less than measurable limit
MP3 Decoding Format: (MPEG1/2 Audio Layer 3) Max. Bit Rate 320 kbps
WMA (Windows Media® Audio) Decoding Format Max. Bit Rate 320 kbps
USB SECTION
USB Standard USB 1.1, USB 2.0
Data Transfer Rate (Full Speed) Max. 12 Mbps
Storage Less than 8 GB (1 partition type)
Compatible Device Mass storage class (except HDD)
Compatible File System FAT 32/16/12
Playable Audio Format MP3/WMA
Max. Current 500 mA
GENERAL
Power Requirement Operating Voltage DC 14.4 V (11 V to 16 V allowance)
Grounding System Negative ground
Allowable Operating Temperature 0°C to +40°C
Dimensions (W × H × D) Installation Size (approx.) 182 mm × 52 mm × 160 mm
Panel Size (approx.) 188 mm × 58 mm × 13 mm
Mass (approx.) 1.3 kg (excluding accessories)
Page 2
(No.MA377)1-3 KD-G447/KD-G357
Design and specifications are subject to change without notice.AUDIO AMPLIFIER SECTION
Maximum Power Output Front/Rear 50 W per channel
Continuous Power Output (RMS) Front/Rear 19 W per channel into 4 -„¦ 40 Hz to 20 000 Hz at no
more than 0.8% total harmonic distortion
Load Impedance 4 -„¦ (4 -„¦ to 8 -„¦ allowance)
Tone Control Range Bass ±12 dB at 60 Hz
Middle ±12 dB at 1 kHz
Treble ±12 dB at 10 kHz
Frequency Response 40 Hz to 20 000 Hz
Signal to Noise Ratio 70 dB
Other Terminals AUX (auxiliary) input jack, USB input jack
TUNER SECTION
Frequency Range FM1/FM2 87.5 MHz to 108.0 MHz
FM3 65.00 MHz to 74.00 MHZ
AM MW: 522 kHz to 1 620 kHz
LW: 144 kHz to 279 kHz
FM Tuner Usable Sensitivity 11.3 dBf (1.0 µV/75 -„¦)
50 dB Quieting Sensitivity 16.3 dBf (1.8 µV/75 -„¦)
Alternate Channel Selectivity (400 kHz) 65 dB
Frequency Response 40 Hz to 15 000 Hz
Stereo Separation 30 dB
MW Tuner Sensitivity/Selectivity 20 µV/35 dB
LW Tuner Sensitivity 50 µV
CD PLAYER SECTION
Type Compact disc player
Signal Detection System Non-contact optical pickup (semiconductor laser)
Number of Channels 2 channels (stereo)
Frequency Response 5 Hz to 20 000 Hz
Dynamic Range 96 dB
Signal-to-Noise Ratio 98 dB
Wow and Flutter Less than measurable limit
MP3 Decoding Format: (MPEG1/2 Audio Layer 3) Max. Bit Rate 320 kbps
WMA (Windows Media® Audio) Decoding Format Max. Bit Rate 320 kbps
USB SECTION
USB Standard USB 1.1, USB 2.0
Data Transfer Rate (Full Speed) Max. 12 Mbps
Storage Less than 8 GB (1 partition type)
Compatible Device Mass storage class (except HDD)
Compatible File System FAT 32/16/12
Playable Audio Format MP3/WMA
Max. Current 500 mA
GENERAL
Power Requirement Operating Voltage DC 14.4 V (11 V to 16 V allowance)
Grounding System Negative ground
Allowable Operating Temperature 0°C to +40°C
Dimensions (W × H × D) Installation Size (approx.) 182 mm × 52 mm × 160 mm
Panel Size (approx.) 188 mm × 58 mm × 13 mm
Mass (approx.) 1.3 kg (excluding accessories)
Page 8
(No.MA377)1-9 1.2 Preventing static electricity
Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged, can destroy the laser
diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.
1.2.1 Grounding to prevent damage by static electricity
Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as laser products.
Be careful to use proper grounding in the area where repairs are being performed.
(1) Ground the workbench
Ground the workbench by laying conductive material (such as a conductive sheet) or an iron plate over it before placing the
traverse unit (optical pickup) on it.
(2) Ground yourself
Use an anti-static wrist strap to release any static electricity built up in your body.
(3) Handling the optical pickup
- In order to maintain quality during transport and before installation, both sides of the laser diode on the replacement optical
pickup are shorted. After replacement, return the shorted parts to their original condition.
(Refer to the text.)
- Do not use a tester to check the condition of the laser diode in the optical pickup. The tester's internal power source can easily
destroy the laser diode.
1.3 Handling the traverse unit (optical pickup)
(1) Do not subject the traverse unit (optical pickup) to strong shocks, as it is a sensitive, complex unit.
(2) Cut off the shorted part of the flexible cable using nippers, etc. after replacing the optical pickup. For specific details, refer to the
replacement procedure in the text. Remove the anti-static pin when replacing the traverse unit. Be careful not to take too long a
time when attaching it to the connector.
(3) Handle the flexible cable carefully as it may break when subjected to strong force.
(4) It is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it.
1.4 Attention when traverse unit is decomposed
*Please refer to "Disassembly method" in the text for the pickup unit.
- Apply solder to the short land before the card wire is disconnected from the connector on the pickup unit.
(If the card wire is disconnected without applying solder, the pickup may be destroyed by static electricity.)
- In the assembly, be sure to remove solder from the short land after connecting the card wire.
1M
(caption)
Anti-static wrist strap
Conductive material
(conductive sheet) or iron plate
Traverse mechanism assemblyPickup Short land section
Card wire
Connector
