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CD-C621H FOR A COMPLETE DESCRIPTION OF THE OPERATION OF THIS UNIT, PLEASE REFER TO THE OPERATION MANUAL. SPECIFICATIONS CD-C621H General Cassette deck section Type: Compact cassette tape Power source: AC 230 V, 50 Hz Frequency response: 50 - 14,000 Hz (Normal tape) Power consumption: Stand-by;...
CD-C621H TROUBLESHOOTING (CD SECTION) When the CD does not function When the CD section does not operate When the objective lens of the optical pickup is dirty,this section may not operate.Clean the objective lens,and check the playback operation.When this section does not operate even after the above step is taken,check the following items.
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CD-C621H • When the turntable fails to stop. Is from 5 V till 2.5V down pulse (approx. 300 ms) Check the SWM3 and the wiring from the IC701 pin 21 to the 2.5V SWM3. input into the IC701 pin 21 when the turntable is rotating?
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CD-C621H • When the CD tray fails to open or close. Check the OPEN CLOSE SW and the wiring from the IC701 Is there following voltage input in specific state of IC701 pin 19? pin 19 to the OPEN CLOSE SW.
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CD-C621H • Playback can only be performed when a disc is loaded. Check the laser diode driver. Is the Focus servo active? (Can you hear it working?) Check the area around IC1(16) - (21) (focus servo circuit). If the disc is not turning, the DRF Does the DRF signal change from "L"...
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CD-C621H • Checking the spin system. Play operation is performed without disc. The turntable rotates a little. The spin driver circuit is normal. Check the periphery of IC1 pins 23 to 27, pin 39, and pin 40, IC2 The turntable fails to rotate or rotates at high speed.
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CD-C621H VOLTAGE FE301 IC302 IC303 IC701 PIN VOLTAGE NO. VOLTAGE NO. VOLTAGE NO. VOLTAGE NO. VOLTAGE NO. VOLTAGE NO. VOLTAGE VOLTAGE 2.5V 2.5V 0V (0V) 2.6V (2.6V) 2V (2V) 4.8V 4.8V 2.5V 2.6V 4.8V 4.8V 0V (0V) 0V (0V) 5V (5V) 2.5V...
CD-C621H WAVEFORMS OF CD CIRCUIT STOP PLAY FOCUS SERCH 0.5ms 0.50 V 10.0 V IC1 20 F.E 0.5ms 10.0 V 0.5ms 5.0 V 0.50 V IC1 54 DRF 0.5ms 1.00 V PLAY 0.5ms NORMAL DISC 1.00 V TN0=01 20ms 1.00 V 0.5ms...
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CD-C621H RECORD SIGNAL FM SIGNAL PLAYBACK SIGNAL CNS11 R-CH A_GND L-CH CD_GND R639 C601 4.7/50 +12V R607 1.5K R608 1.5K C605 R605 1.5K R606 1.5K 4.7/50 R603 1.5K R604 1.5K C603 R602 1.5K R601 1.5K 4.7/50 C611 0.033 C612 0.033...
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CD-C621H D SIGNAL CD SIGNAL R633 L-CH R631 C631 JK601 390P VIDEO C602 R634 C632 R632 4.7/50 R642 R608 1.5K 390P R-CH C606 C654 R606 1.5K 4.7/50 4.7/50 R604 1.5K R640 47K D601 R602 1.5K 1SS133 D602 C612 0.033 C604...
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CD-C621H P33 8 - H TO DISPLAY PW P35 12 - D TO CD SERVO PWB CNS701 CNP11 FC701 CNS11 1 2 3 4 5 6 MAIN PWB-A1 COLOR TABLE BROWN R D ( R ) C605 C651 ORANGE YELLOW...
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CD-C621H P33 8 - H TO DISPLAY PWB CNS701 P29 12 - F FC701 TO TUNER PWB CNP303 R156 Q114 Q104 Q103 C156 Q122 B C E C136 R142 C134 R111 R170 Q105 C116 R112 C106 R118 C114 C142 C140...
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CD-C621H R D(R) WH (W) COLOR TABLE BROWN ORANGE YELLOW GREEN BLUE VIOLET GRAY WHITE BLACK PINK SW707 SW706 LED704 LED703 LED702 LED701 DISC3 DISC2 RS701 RS704 RS703 RS702 FW702 SW705 RD06 DISC1 RD05 SW704 21 20 TIMER/ SLEEP RD04...
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CD-C621H SWM3 P32 5 - H F. P. CNSM1 CNPM1 TO DISPLAY PWB FWM2 FWM1 PHM1 SWM4 CNPM2 F. A. S SOLM1 TAPE MECHANISM SOLENOID (254-8) PWB-F SWM5 TAPE MOTOR(254-7) TAPE MECHANISM ASSEMBLY P31 10 - E TO MAIN PWB...
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CD-C621H ZD61 3 2 1 CNP2 CNP10 1 2 3 4 5 6 7 8 9 10 CNP3 CD SERVO PWB-B PICKUP UNIT(306) CNS1A CNS1B CNS2A CNS2B • The numbers are waveform numbers shown in page 37. Figure 35 WIRING SIDE OF P.W.BOARD (7/7)