SHARE QT-CD250 Service Manual

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IMPORTANT SERVICE NOTEST (FOR U.S.A. ONLY) .................................................................................................... 2

SPECIFICATIONS ............................................................................................................................................................. 2

NAMES OF PARTS ........................................................................................................................................................... 3

OPERATION MANUAL ...................................................................................................................................................... 4

DISASSEMBLY .................................................................................................................................................................. 5

REMOVING AND REINSTALLING THE MAIN PARTS ..................................................................................................... 5

ADJUSTMENT ................................................................................................................................................................... 7

NOTES ON SCHEMATIC DIAGRAM .............................................................................................................................. 11

TYPES OF TRANSISTOR ............................................................................................................................................... 11

SCHEMATIC DIAGRAM .................................................................................................................................................. 12

WIRING SIDE OF P.W.BOARD ....................................................................................................................................... 14

WAVEFORMS OF CD CIRCUIT ...................................................................................................................................... 16

TROUBLESHOOTING (CD SECTION) ........................................................................................................................... 17

FUNCTION TABLE OF IC ................................................................................................................................................ 21

PARTS GUIDE/EXPLODED VIEW

PACKING OF THE SET (FOR U.S.A. ONLY)

SERVICE MANUAL

CONTENTS

SHARP CORPORATION

QT-CD250

• In the interests of user-safety the set should be restored to its

original condition and only parts identical to those specified should

be used.

This document has been published to be used

for after sales service only.

The contents are subject to change without notice.

QT-CD250

No. S2014QTCD250/

Page

Table of Contents

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Summary of Contents for SHARE QT-CD250

Page 1: Table Of Contents
QT-CD250 SERVICE MANUAL No. S2014QTCD250/ QT-CD250 • In the interests of user-safety the set should be restored to its original condition and only parts identical to those specified should be used. CONTENTS Page IMPORTANT SERVICE NOTEST (FOR U.S.A. ONLY) ....................2 SPECIFICATIONS ................................
Page 2: Important Service Notest (For U.s.a. Only)
QT-CD250 FOR A COMPLETE DESCRIPTION OF THE OPERATION OF THIS UNIT, PLEASE REFER TO THE OPERATION MANUAL. IMPORTANT SERVICE NOTES (FOR U.S.A. ONLY) BEFORE RETURNING THE AUDIO PRODUCT (Fire & Shock Hazard) Before returning the audio product to the user, perform the following safety checks.
Page 3: Names Of Parts
QT-CD250 NAMES OF PARTS 2 3 4 5 6 25 26 27 28 20 21 22 23 (CD) Pause Indicator (TAPE) Record Button Extra Bass Indicator (TAPE) Play Button (TUNER) Memory Indicator (TAPE) Rewind Button (TUNER) FM Stereo Mode Indicator...
Page 4: Operation Manual
QT-CD250 OPERATION MANUAL – 4 –...
Page 5: Disassembly
QT-CD250 DISASSEMBLY (C4)x4 (C3)x2 ø3x10mm Caution on Disassembly (C1)x2 ø3x12mm Follow the below-mentioned notes when disassembling the Switch PWB (D3)x1 unit and reassembling it, to keep it safe and ensure excellent ø2.5x8mm performance: 1. Take cassette tape and compact disc out of the unit.
Page 6 QT-CD250 TAPE MECHANISM SECTION Hook (A1) x1 Perform steps 1 to 6 of the disassembly method to remove the ø2x7mm (A2)x2 tape mechanism. (See page 5.) (A1) x1 ø2x3mm How to remove the record / playback and erase Record/Playback Erase Head heads (See Fig.
Page 7: Adjustment
QT-CD250 ADJUSTMENT • AM IF/RF MECHANISM SECTION Signal generator: 400 Hz, 30%, AM modulated • Driving Force Check Test Stage Frequency Frequency Setting/ Instrument Torque Meter Specified Value Display Adjusting Connection PLAY: TW-2412 Over 120 g Parts AM IF 450 kHz 1,720 kHz •...
Page 8 QT-CD250 A. CD TEST MODE Set the function switch to "CD" when pressing the "REVIEW(PRESET DOWN )" button together with "STOP(TUNING DOWN)" button. Step-1. CD Pickup can be move when press the "CUE" button either "REVIEW" button. "CUE" button : CD Pickup move to out side of disc.
Page 9 QT-CD250 B. TUNER TEST MODE Set the function switch to "TUNER" when pressing the "REVIEW(PRESET DOWN )" button together with "BAND(REPEAT)" button. The LCD displays indicate the "TunEr" for several seconds. after that, the LCD displays indicate to the normal frequency.
Page 10 QT-CD250 D. VOLUME TEST MODE Set the function switch to "POWER ON (TAPE PLAY, TUNER or CD)" when pressing the "REVIEW(PRESET DOWN )" button together with "PLAY/PAUSE (TUNING UP)" button. The LCD display do not indicate the VOLUME level at this time.
Page 11: Notes On Schematic Diagram
QT-CD250 NOTES ON SCHEMATIC DIAGRAM • Resistor: 1. Tuner To differentiate the units of resistors, the symbol as K and M ( ): AM mode are used: the symbol K means 1000 ohm and the symbol M Marking except for ( ): FM mode means 1000 kohm and the resistor without any symbol is an 2.
Page 12: Schematic Diagram
QT-CD250 SW810 LASER DRIVER Q801 CD LID KTA1266 GR 4.4V(ON:2.8V) 1.4V(ON:1.9V) OPEN/CLOSE C815 R801 C816 C825 47/16 0.022 47/16 IC801 3.7V(ON:2.1V) PICK-UP UNIT SERVO PRE AMP. C802 TA2109F 0.022 R802 R804 C826 2.2K 1.9V C801 4.4V R805 R807 0.01 1.9V...
Page 13 QT-CD250 FM SIGNAL AM SIGNAL C825 47/16 CD SIGNAL R871 C870 4.7K 100P R824 PLAYBACK SIGNAL C826 R872 4.7K RECORD SIGNAL 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 5.0V...
Page 14: Wiring Side Of P.w.board
QT-CD250 SPEAKERS L-CH SP201 SP202 R-CH CNP101 1 2 3 4 C351 L301 PLAY SW102 RECORD/ PLAYBACK C354 R103 R104 R352 R121 R353 C353 HPJ201 HEADPHONES CNS201 R126 R227 IC101 R124 D102 C123 C249 R855 CNP201 1 2 3 SW808...
Page 15 QT-CD250 TAPE ERASE HEAD RECORD/PLAYBACK (240-5) HEAD(240-4) (241) (241) SW601 M601 TAPE MAIN TAPE MOTOR (240-7) (240-6) TERMINAL B PWB-A6 BATTERYS DC4.5V ["AA" SIZE(UM/SUM-3, R6 or HP7)battery x 3] CNS101 (241) TERMINAL A PWB-A5 (230) T651 BATTERYS POWER TRANSFORMER DC9 V [ "D" size(UM/SUM-1,...
Page 16: Waveforms Of Cd Circuit
QT-CD250 WAVEFORMS OF CD CIRCUIT NO DISC FOCUS SEARCH STOP PLAY TMAX IC802 66pin IC802 50pin SBOK IC803 20pin IC802 45pin IC802 72pin IC803 21pin FOCUS SEARCH TOC IL STOP PLAY IC802 74pin IC802 64pin IC802 62pin IC802 67pin IC802 64pin...
Page 17: Troubleshooting (Cd Section)
QT-CD250 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.
Page 18 QT-CD250 • Laser failure. Is +7.5V applied to the Collector of Q206 ? Check the PWB pattern of Q206. Check the PWB Patten of IC204 and Q806. Is +5V applied to the collector of Q204 and Q806 ? Check the PWB pattern between collector of Q806 and pin 75 of Is +5V applied to the pin 75 (VDD) and pin 96 (MVDD) of IC802, and emiter of Q806 and Q804 and pin 96 of IC802.
Page 19 QT-CD250 • Focus servo sawtooth wave failure. IC802 is faulty. Is sawtooh wave output to the pin 66 (FOO) of IC802 ? 1.5~2.5sec Check the PWB pattern of IC803. Is +7.5V applied to the pins 1 and 30 (VCC) of IC803 ? Check the PWB pattern of IC803.
Page 20 QT-CD250 • Track search failure Does the sled motor run in FF/REW state when the CD Check as stated in item "SLED MOTOR OPERATION FAILURE". TEST MODE is set? Is the following wave output to the pin 67 (TRO) of IC802 IC802 failure.
Page 21: Function Table Of Ic
QT-CD250 FUNCTION TABLE OF IC IC51 VHiLC72121/-1: Electronic Tuning (LC72121) (1/2) Terminal Input/Output Pin No. Port Name Function Name Xtal Output Crystal oscillator connection.(4.5 MHz/7.2 MHz) Ground VSSX Output Ground terminal for the crystal oscillation circuit system of LC72121. Chip enable...
Page 22 QT-CD250 IC51 VHiLC72121/-1: Electronic Tuning (LC72121) (2/2) Terminal Input/Output Pin No. Port Name Function Name Local oscillation, Signal input AMIN Input Serial data input: AMIN is selected when DVS = 0 is set. When serial data input SNS = 1 is set: Input frequency is 2-40 MHz.
Page 23 QT-CD250 IC1 VHiTA2104BN-1: FM /AM IF MPX. (TA2104BN) FM RF OUT AM RF IN FM RF FM OSC ST IND DET OUT LPF1 LPF2 AM OSC IFREQ MPX IN OSC OUT BUFF DECODE DIYIDE BUFF BUFF LEVEL BUFF ST/MO FM/AM...
Page 24 QT-CD250 IC802 VHiTC9457F2-1: Servo/Signal Control (TC9457F2) (1/4) Pin No. Port Name Terminal Name Input/Output Function (OT5)S1 SEG1 Output Segment signal output to the LCD panel. (OT6)S2 SEG2 Output Up to 72 segments in a matrix with COM1 to COM4 can be displayed.
Page 25 QT-CD250 IC802 VHiTC9457F2-1: Servo/Signal Control (TC9457F2) (2/4) Pin No. Port Name Terminal Name Input/Output Function (S12)P4-1 Input 3-bit CMOS I/O ports. (SO/S11/ Output DI: Tuner Data Input pin. SDA)P4-2 DO: Tuner Data Output pin. (SCK/SCL) Output CL: Tuner/Volume Clock Output pin.
Page 26 QT-CD250 IC802 VHiTC9457F2-1: Servo/Signal Control (TC9457F2) (3/4) Pin No. Port Name Terminal Name Input/Output Function SBAD SBAD Input/Output Subbeam add signal input pin. Input/Output Tracking error input pin. This input is read when tracking servo is on. TEZI TEZI Input/Output Tracking error zero-cross input pin.
Page 27 QT-CD250 IC802 VHiTC9457F2-1: Servo/Signal Control (TC9457F2) (4/4) Pin No. Port Name Terminal Name Input/Output Function /HOLD HOLD Input This pin is used to input a signal that requests or clears the hold mode. Normally, use this pin for CD mode select signal input or battery detection signal input.
Page 28 QT-CD250 — M E M O — – 28 –...
Page 29 QT-CD250 PARTS GUIDE QT-CD250 MODEL “HOW TO ORDER REPLACEMENT PARTS” To have your order filled promptly and correctly, please furnish the For U.S.A. only following information. Contact your nearest SHARP Parts Distributor to order. 1. MODEL NUMBER 2. REF. No.
Page 30 QT-CD250 PRICE PRICE DESCRIPTION PARTS CODE PARTS CODE DESCRIPTION RANK RANK INTEGRATED CIRCUITS X801 RCRM-0002SJZZ AE Ceramic,16.93 MHz X802 RCRM-0003SJZZ AK Ceramic,4.19 MHz VHITA2104BN-1 AQ FM/AM IF MPX.,TA2104BN CAPACITORS IC51 VHILC72121/-1 AN Electronic Tuning,LC72121 IC101 VHIBA3311L/-1 AK REC./P.B.Equalizer Amp., BA3311L...
Page 31 QT-CD250 PRICE PRICE DESCRIPTION PARTS CODE DESCRIPTION PARTS CODE RANK RANK C243,244 VCKYPA1HB331K AA 330 pF,50V R71,72 VRD-ST2CD472J AA 4.7 kohms,1/6W AB 1 µF,50V,Electrolytic C245 RC-GZA105AF1H R73,74 VRD-ST2CD332J AA 3.3 kohms,1/6W AB 10 µF,16V,Electrolytic C246 RC-GZA106AF1C VRD-ST2CD821J AA 820 ohms,1/6W AB 220 µF,10V,Electrolytic...
Page 32 QT-CD250 PRICE PRICE DESCRIPTION PARTS CODE PARTS CODE DESCRIPTION RANK RANK R850 VRD-ST2CD152J AA 1.5 kohms,1/6W M702 RMOTV0408AFM3 J AN Motor with Chassis [Spindle] R851~853 VRD-ST2CD222J AA 2.2 kohms,1/6W SW702 QSW-F9001AWZZ AE Switch,Push Type [Pickup In] R854 VRD-ST2CD101J AA 100 ohm,1/6W...
Page 33 QT-CD250 PRICE DESCRIPTION PARTS CODE RANK ACCESSORIES QACCU0001SJ00 AR AC Power Supply Cord TINSE0040SJZZ AC Operation Manual TLABZ SJZZ Label,Feature RRMCG0023SJSA J AU Remoto Control Battery Lid,Remoto Control P.W.B. ASSEMBLY (Not Replacement Item) PWB-A1~7 DCEK-0008SJ03 — Main/CD Control/Power/Switch/ Terminal A/Terminal B/Washer (Combined Ass’y)
Page 34 QT-CD250 703x2 M702 M701 305x2 SW702 PWB-B Figure 5 CD MECHANISM EXPLODED VIEW – 5 –...
Page 35 QT-CD250 605x2 235 231 240(240-1, 240-2, 240-3, 603x2 240-4, 240-5 605x2 240-6(M601), 204-1 240-7(SW601)) 204-2 204-3 SW810 PWB-A7 604x4 TAPE MECHANISM Silicon Silicon PWB-A1 Grease Q206 Grease 607x3 MECHANISM PWB-A2 602x3 603x6 605x2 LCD801 605x2 SO651 603x4 T651 PWB-A4 604x7...
Page 36: Packing Of The Set (For U.s.a Only)
QT-CD250 PACKING OF THE SET (FOR U.S.A ONLY) • Setting position of switches and knobs Tape Mechanism Control STOP STATE FUNCTION SELECTOR OFF/TAPE Polyethylene Bag, Unit SSAKH0001SJZZ Operation Manual AC Power Supply Cord Packing Add., Left/Right SPAKA0036SJZZ Polyethylene Bag, AC Power Supply Cord...