sony_wm-gx780_wm-gx788_ver.1.2_sm.pdf

WM-GX780/GX788 US Model AEP Model WM-GX788 E Model Chinese Model WM-GX780/GX788 Tourist Model WM-GX788 SERVICE MANUAL Ver. 1.2 2006.04 RADIO CASSETTE-CORDER Model Name Using Similar MechanismNEW Tape Transport Mechanism TypeMF-WMGX788-162 SPECIFICATIONS Sony Corporation Personal Audio Division Published by Sony Techno Create Corporation 9-877-201-03 2006D16-1 2006.04 Radio section Frequency range FM:87.5 - 108 MHz AM:530 - 1 710 kHz (North, Central, and South America) 531 - 1 602 kHz (other countries/regions) Tape section Frequency response Playback: 40 - 15 000 Hz Recording/playback: 100 - 8 000 Hz Output Headphones (i) jack Load impedance 8 - 300 Input Microphone (MIC) jack General Power requirements 1.5 V Rechargeable battery One R6 (size AA) battery Dimensions (w/h/d) Approx. 77.1 108.0 22.5 mm (318 438 2932 inches) excl. projecting parts and controls Mass Approx. 152 g (5.4 oz) (main unit only) Supplied accessories AC power adaptor (1) Battery case (1) Stereo headphones or earphones with remote control (1) Charging stand (1) AC plug adaptor (1) (Saudi Arabian model only) Rechargeable battery (NH-14WM(A), 1.2 V, 1 350 mAh (min), Ni-MH) (1) Rechargeable battery carrying case (1) Carrying pouch (1) Stereo microphone (1) Design and specifications are subject to change without notice. Photo: WM-GX788 Notes on chip component replacement Never reuse a disconnected chip component. Notice that the minus side of a tantalum capacitor may be damaged by heat. Flexible Circuit Board Repairing Keep the temperature of soldering iron around 270C during repairing. Do not touch the soldering iron on the same conductor of the circuit board (within 3 times). Be careful not to apply force on the conductor when soldering or unsoldering. SAFETY-RELATED COMPONENT WARNING! COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE WITH MARK 0 ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY. TABLE OF CONTENTS WM-GX780/GX788 2 UNLEADED SOLDER Boards requiring use of unleaded solder are printed with the lead- free mark (LF) indicating the solder contains no lead. (Caution: Some printed circuit boards may not come printed with the lead free mark due to their particular size) : LEAD FREE MARK Unleaded solder has the following characteristics. Unleaded solder melts at a temperature about 40 C higher than ordinary solder. Ordinary soldering irons can be used but the iron tip has to be applied to the solder joint for a slightly longer time. Soldering irons using a temperature regulator should be set to about 350 C . Caution: The printed pattern (copper foil) may peel away if the heated tip is applied for too long, so be careful! Strong viscosity Unleaded solder is more viscous (sticky, less prone to flow) than ordinary solder so use caution not to let solder bridges occur such as on IC pins, etc. Usable with ordinary solder It is best to use only unleaded solder but unleaded solder may also be added to ordinary solder. 1. SERVICE NOTE 3 2. GENERAL 5 3. DISASSEMBLY 3-1. Case Block Assy 6 3-2. Button Rec, Button Assy 7 3-3. Cassette Lid Assy 7 3-4. Ornament Block Assy Reel, Flexible Retainer 8 3-5. MAIN Board, Belt (F0) 8 3-6. Motor (M901) 9 3-7. Bracket (cassette) Assy, Holder (FA) Assy 9 3-8. Pinch Lever (RA) Assy, Pinch Lever (NA) Assy 10 3-9. Magnetic Head (HP901) 10 4. MECHANICAL ADJUSTMENT11 5. ELECTRICAL ADJUSTMENT11 6. DIAGRAMS 12 6-1. Block Diagram 13 6-2. Printed Wiring Board (Side A)14 6-3. Printed Wiring Board (Side B)15 6-4. Schematic Diagram (1/2) 16 6-5. Schematic Diagram (2/2) 17 6-6. IC Block Diagrams 18 6-7. IC Pin Function Discription 19 7. EXPLODED VIEWS 7-1. Case Section 21 7-2. Main Section 22 7-3. Mechanism Deck Section (MF-WMGX788-162) 23 8. ELECTRICAL PARTS LIST 24 WM-GX780/GX788 3 SECTION 1 SERVICE NOTE Service Mode The service mode enables to operate the mechanism of WM-GX780/ GX788 while the MAIN board is opened. Rotation of the idler gear (A) (S side) is detected using the photo- reflector (PH701) in the WM-GX780/GX788. PH701 is located on the MAIN board, therefore the rotation of the idler gear (A) (S side) cannot be detected by PH701 when the MAIN board is removed. As a result, the motor cannot be controlled and cannot run correctly. To repair the machine after the MAIN board is removed while the main power is turned on, follow the procedures as described below. 1. Setting 1)Remove the cabinets referring to section “3. DISASSEMBLY”. Open the MAIN board. 2)Connect the motor (M601) and the plunger solenoid (PM901) to the MAIN board using the jumper wires. When the extension jig (1-769-143-11) (10 wires as a set) is used, they can be connected easily. 3)Short the TAPE DETECT switch (S303), REV TUME switch (S503), FWD TUME switch (S502) and ATS switch (S302). 4)Connect an AF oscillator to resistor (R712). 5)Connect DC 1.3 V from external regulated power supply to and terminals of the battery. 2. PRE-SET status The PLAY, FF and REW modes can be entered only from the PRE- SET status. 1)Check that the slider (NR) is in the center position (S801), and the FWD/REV switch is also in the center position. When these switches are not in the center position, set them to the PRE-SET status as follows. 2)Move the FWD/REV switch (S801) to the same position as the slider (NR) is set. 3)The slider (NR) can be moved when the main power of the regulated power supply is turned OFF once then back ON. Move the FWD/REV switch (S801) to the center position in synchronism with the timing when the slider (NR) is moved. 3. FF, REW modes 1)Check that the PRE-SET status is set. 2)Connect square wave or sine wave to resistor (R712). (See illustration below.) 3)Press the x switch (S703) to enter the STOP mode. 4)Press the FF PRESET+ switch (S708) and the REW PRESET switch (S707). 4. PLAY mode 1)Check that the PRE-SET status is set. 2)Connect square wave or sine wave to resistor (R712). (See illustration below.) 3)Press the x switch (S703) to enter the STOP mode. 4)When the nNREPEAT switch (S709) of the MAIN board is pressed, the slider (NR) moves once to the F side then moves to the R side. When the FWD/REV switch (S801) is pressed in the synchronism with the above timing, the machine can enter the PLAY (R side) mode. Press the nNREPEAT switch (S709) again, and move the FWD/REV switch (S801) in the synchronism with the motion of slider (NR). It enables the machine to enter into the PLAY (F side) mode. Note 1: When you fail to enter the PLAY mode, re-start from step 1) PRE-SET status. Note 2: Regarding the nNREPEAT (S709), x (S703), FF PRESET+ (S708), and REW PRESET (S707) switches, use these switches of the remote control unit as much as possible. Note 3: If a headphones are used, the beep sound shows the timing of the FWD/REV switch (S801). MAIN BOARD (SIDE B) ENTER (S702) REC (S710) RADIO ON/ BAND (S704) MENU (S706) R710 (Side A) SET (S705) (S801) FWDSTOPREV Battery terminal # Battery terminal 3 Sine wave 10 Hz, -3.5 dB OSC Plunger (PM901) Short Short TAPE DETECT SWITCH (S303) REV TUME SWITCH (S503) YREPEAT (S709) FF/PRESET+ (S708) REW/PRESET (S707) xRADIO OFF (S703) FWD TUME SWITCH (S502) ATS SWITCH (S302) M601M WM-GX780/GX788 4 Slider (NR) Tape drive mechanism Tape drive mechanism in PLAY mode Tape drive mechanism in FF modeTape drive mechanism in REW mode Slider (NR) Center F side R side Insert Flywheel (N) Pulley (Reverse) Clutch Assy(F) Motor Pulley Gear (REEL)(S side)Gear (REEL)(T side) Gear (NR) (FWD : Left side REV : Right side) Idler Gear(B) Idler Gear (A)(S side) Idler Gear (A)(T side) Insert Flywheel (R) Cam Gear Gear (Y) Insert Flywheel (N) Pulley (Reverse) Clutch Assy(F) Motor Pulley Gear (REEL)(T side) Idler Gear (A)(T side) Insert Flywheel (R) Cam Gear Gear (Y) Gear (FR) (FF : Left side) Insert Flywheel (N) Pulley (Reverse) Clutch Assy(F) Motor Pulley Gear (REEL)(S side) Idler Gear (A)(S side) Insert Flywheel (R) Cam Gear Gear (Y) Gear (FR) (REW : Right side) WM-GX780/GX788 5 SECTION 2 GENERAL LOCATION OF CONTROLS This section is extracted from instruction manual. x VOL* VOL HOLD HOLD YREPEAT* REW/REVIEW Yx REW MIC* ISS x REC Plug in firmly. i FF + MENU SET FF/CUE MENU SET ENTER/ COUNTER RESET SET MENU Tape counter HOLD HOLDSOUND MODE SPEED CONTROL REW SET MENU FF + RADIO ON/BAND ENTER RADIO OFF TUNE/PRESET /+ RADIO ON/BAND OFF WM-GX780/GX788 6 SECTION 3 DISASSEMBLY Note :Disassemble the unit in the order as shown below. Note :Follow the disassembly procedure in the numerical order given. 3-1.Case Block Assy CASE BLOCK ASSY MAIN BOARD, BELT (F0) SET BUTTON REC, BUTTON ASSY CASSETTE LID ASSY ORNAMENT BLOCK ASSY REEL, FLEXIBLE RETAINER MOTOR (M901) BRACKET (CASSETTE) ASSY, HOLDER (FA) ASSY PINCH LEVER (RA) ASSY, PINCH LEVER (NA) ASSY MAGNETIC HEAD (HP901) 1Open the battery lid. 3battery lid 4two screws (M1.4)(EG) 6two screws (M1.4)(EG) 5screw (M1.4)(EG) Note: On installation case block assy adjust the S501 and knob (iss). knob (iss) 7Remove the case block assy in the direction of the arrow. S501 2claw WM-GX780/GX788 7 3-2.Button Rec, Button Assy 3-3.Cassette Lid Assy 1rec spring 3torion spring (hold) 2button rec 4button assy 5knob (hold) 2two screws (M1.4)(EG) 1screw (M1.4)(EG) 3Slide the knob (open) in the direction of the arrow. 5cassette lid assy 4shaft WM-GX780/GX788 8 3-4.Ornament Block Assy Reel, Flexible Retainer 3-5.MAIN Board, Belt (F0) 6screw (M1.4) 7flexible retainer 1claw 1claw 2claw 3claw 3claw 4boss 5ornament block assy reel 6screw (M1.4) 5two screws 3Remove two solders of plunger solenoid. 4Remove four solders of leaf switch. 7flexible board (head) 8MAIN board 1Remove four solders of motor. 9belt (F0) 2Remove three solders of ATS flexible board. WM-GX780/GX788 9 3-6.Motor (M901) 3-7.Bracket (cassette) Assy, Holder (FA) Assy 1two screws (M1.4) 2motor (M901) 3motor retainer (F1) 6flexible board (head) 1two screws (M1.4 1.6) 3screw (M1.4) 2lock lever (B) 5bracket (cassette) assy 8holder (FA) assy 4shaft 7shaft WM-GX780/GX788 10 3-8.Pinch Lever (RA) Assy, Pinch Lever (NA) Assy 3-9.Magnetic Head (HP901) 1claw 2Remove the pinch lever (RA) assy in the dereciton of the arrow. 4Remove the pinch lever (NA) assy in the direction of the arrow. 3claw 1claw 2Remove the magnetic head (HP901) in the direction of the arrow. 1111 WM-GX780/GX788 SECTION 4 MECHANICAL ADJUSTMENT SECTION 5 ELECTRICAL ADJUSTMENT PRECAUTION 1.Specified voltage: 1.3 V (DC) 2.Switch and control position MENU switch HOLD: OFF VOL: MAX ISS: 1 TAPE SECTION Tape Speed Adjustment Procedure: 1.Enter the FWD playback mode. 2.Confirm RV602 at center value. (mechanical center) 3.Adjust RV601 so that the value of the frequency counter reading becomes 3,000 Hz. Specification value: Frequency counter 2,955 Hz 3,045 Hz 4.Check that the frequency deviation at the beginning and ending of a tape is within 1.5 % (45 Hz). 5.Select switch to 2X (2.4 cm/s), then depress play button in and adjust RV603 (2,955 Hz3,045 Hz) at tape center. PRECAUTION 1.Clean the following parts with a denatured-alcohol-moistened swab: record/playback/erase headpinch roller rubber beltscapstan 2.Demagnetize the record/playback/erase head with a head demagnetizer. (Do not bring a head demagnetizer close to the erase head.) 3.The adjustments should be performed with the rated power supply voltage unless otherwise noted. Torque Measurement Signal 3 kHz, 0 dB 3 kHz, 0 dB Used for Tape Speed Adjustment Tape Speed Adjustment Tape WS-48A (4.8cm/s) WS-24CC (2.4cm/s) Test tape WS-48A/24CC (3kHz, 0dB) Set i REMOTE jack (J301) 16 Frequency counter + MAIN BOARD SIDE B Adjustment Parts Location : MAIN BOARD SIDE A Mode FWD FWD Back Tension REV REV Back Tension FF, REW Torque Meter CQ-102C CQ-102C CQ-102RC CQ-102RC CQ-201B Meter Reading 1.47 to 2.45 mNm (15 to 25 gcm) (0.21 to 0.34 ozinch) Less than 0.20 mNm (Less than 2.0gcm) (Less than 0.028 ozinch) 1.47 to 2.45 mNm (15 to 25 gcm) (0.21 to 0.34 ozinch) Less than 0.20 mNm (Less than 2.0gcm) (Less than 0.028 ozinch) More than 4.90 mNm (More than 50 gcm) (More than 0.69 ozinch) CT1 L1 L5 L5 : AM frequency coverage adjustment CT1 : AM frequency coverage adjustment L1 : FM frequency coverage adjustment J501 J301 RV603RV601 WS-48A (4.8 cm/s) adjustment WS-24CC (24 cm/s) adjustment AM BAND switch : AM FM BAND : FM Repeat the procedures in each adjustment several times. AM FREQUENCY COVERAGE ADJUSTMENT Adjust for a maximum reading on level meter. L5 620 kHz (US) 621 kHz (Except US) CT1 1400 kHz (US) 1395 kHz (Except US) TUNER SECTION 0.01F FM RF signal generator to ANT 22.5kHz frequency deviation by 400Hz signal. Output level : as low as possible Put the lead-wire antenna close to the set. 30% amplitude modulation by 400Hz signal. Output level : as low as possible AM RF signal generator 16 set + level meter i REMOTE jack (J301) 0dB=1V FM FREQUENCY COVERAGE ADJUSTMENT Adjust for a maximum reading on level meter. L176 MHz Confirmation108 MHz 1212 WM-GX780/GX788 Note on Schematic Diagram: All capacitors are in F unless otherwise noted. pF: F 50 WV or less are not indicated except for electrolytics and tantalums. All resistors are in and 1/4 W or less unless otherwise specified. f: internal component. C : panel designation. A : B+ Line. H : adjustment for repair. Power voltage is dc 1.5 V and fed with regulated dc power supply from battery terminal. Voltages and waveforms are dc with respect to ground under no-signal (detuned) conditions. : impossible to measure Main board (1/2) no mark: FM/AM, TAPE STOP () : FM : AM : TAPE PB Main board (2/2) no mark: REC / PB () : REC : PB Voltages are taken with a VOM (Input impedance 10 M). Voltage variations may be noted due to normal produc- tion tolerances. Waveforms are taken with a oscilloscope. Voltage variations may be noted due to normal produc- tion tolerances. Circled numbers refer to waveforms. Signal path. E: PB a: REC F: FM Waveform Note on Printed Wiring Board: Y : parts extracted from the conductor side. b : Pattern from the side which enables seeing. Caution: Pattern face side:Parts on the pattern face side seen from (Side A)the pattern face are indicated. Parts face side:Parts on the parts face side seen from (Side B)the parts face are indicated. SECTION 6 DIAGRAMS Note for Printed Wiring Board and Schematic Diagrams 9MHz 1T401 DD CON OUT 100nsec/div 5V/div 75kHz 2IC701 ua XOUT 5sec/div 0.5V/div Abbreviation CH : Chinese model. EA : Soudi Arabia model. JE: Tourist model. HK : Hong Kong model. KR : Korea model. 1313 WM-GX780/GX788 6-1. Block Diagram : FM : PB : REC R-CH R-CH L FWD REC/PB HEAD R R-CH L REV REC/PB HEAD R FWD ERACE HEAD REV 1 5 1 24 18 3 DR START 2 8 U W V IN+VREF 7 1214 PRE AMP 28 29 AMS DET R-CH REMOTE DATA ANT POWER AMP-L POWER AMP-C BUFF Q2 RV SW Q304 MB/GRV SW Q303 IC301(1/3) IC301(3/3) IC601 MOTOR DRIVER 5 54 F/R CONT 51 LOCAL/DX 40 REC CTRL 63 BST CTL 46