S/M No. : K3050MECHA Service Manual VCR MECHANISM UNIT (K50 / K30-MECHA DECK) DAEWOO ELECTRONICS CO., LTD. http : //svc.dwe.co.kr March.
CONTENTS 1. MECHANISM DESCRIPTION .................................................................................................2 2. ASSEMBLY DIAGRAM & MAJOR PARTS CHECK ..............................................................5 3. DISASSEMBLY AND REPLACEMENT ................................................................................12 4. MECHANICAL ADJUSTMENT..............................................................................................22 5.
1.DESCRIPTIONOFTHEMECHANISM 1-1 CHARACTERISTIC OF THE K30-DECK MECHANISM 1) K30-MECHA DECK follows the VHS standard. 2) K30-MECHA DECK uses three motors (DRUM MOTOR, CAPSTAN MOTOR and L/C MOTOR) 3) K30-MECHA DECK uses L/C MOTOR to drive FRONT LOADING. 4) K30-MECHA DECK recognizes each mode by using a 4-BIT MODE signal. This 4-BIT MODE signal is generated by the CAM SWITCH which is driven by the L/C MOTOR. 5) K30-MECHA DECK is operated by 7 MODES (EJECT/INITIAL/REV/IDLE/PLAY, STOP, SLOW/BRAKE/FF & REW).
1-2 WIRE DIAGRAM 1-2-1) WIRE DIAGRAM 3
1-2-2) CONNECTOR PIN ARRANGEMENT CN-1 (2 HEAD MONO) CN-A 1 SP-L 1 GND 2 COMMON 2 DRUM SPD CTL 3 SP-R 3 Vcc 4 GND 4 DRUM FG 5 DRUM PG 6 NON CONNECT 7 NON CONNECT CN-B CN-1 (4 HEAD MONO) 1 FE HEAD 2 GND CN-C CN-2 1 SP-L 1 L/C MT (+) 1 EVER 5V 2 COMMON 2 L/C MT (–) 2 CAPSTAN F/R 3 SP-R 3 GND 3 CAPSTAN FG 4 GND 4 CAM D 4 CTL-REF 5 EP-R 5 CAM C 5 CTL 6 COMMON 6 CAM B 6 I-LIMIT 7 EP-L 7 CAM A 7 CAPSTAN M/T 12V/18V 8 GND 9 IC GND 10 NON
2.ASSEMBLYDIAGRAM&MAJORPARTSCHECK 2-1. ASSEMBLING DIAGRAM 2-1-1) ASSEMBLING DIAGRAM OF DECK ASS'Y A. TOP VIEW 8 9 7 6 5 ! 4 @ 3 # 2 $ % ^ & * ( 1. FE HEAD 2. S SLANT POLE ASS'Y 3. TENSION BAND ASS'Y 4. REEL TABLE 5. MAIN BASE ASS'Y 6. RECORD SAFETY LEVER 7. S SUB BRAKE ASS'Y 8. S MAIN BRAKE ASS'Y 9. IDLER PLATE TOTAL ASS'Y 10. T MAIN BRAKE ASS'Y ) 1 11. T-SUB BRAKE ASS'Y 12. RELAY LEVER 13. CAPSTAN MOTOR 14. PINCH LEVER TOTAL ASS'Y 15. L/C BRKT TOTAL ASS'Y 16. CAM GEAR 17.
B. BOTTOM VIEW 1. CAPSTAN MOTOR 2. F/L RACK 3. CONNECT PLATE 4. REEL BELT 5. REEL GEAR TOTAL ASS'Y 6. RECORD SAFETY LEVER 7. L LOADING ASS'Y 8. R LOADING ASS'Y 9. DRUM TOTAL ASS'Y 10.
2-1-2) PARTS LOCATION OF FRONT LOADING ASS'Y A. TOP VIEW B.
2-2. PERIODIC MAINTENANCE AND SERVICE SCHEDULE 2-2-1) PERIODIC MAINTENANCE AND SERVICE SCHEDULE A. In order to effectively maintain the excellent performance and fully utilize the features of this apparatus, and to lengthen the life of the mechanism and tapes, we strongly urge you to perform periodic maintenance and inspection, as described below. After repairing, do the maintenance described below, irrespective of the length of time in use. B.
2-2-3) SERVICE SCHEDULE FOR THE MAJOR PARTS The following parts should receive periodic service, according to the recommended intervals. PERIODIC SERVICE (TIME) NAME DRUM TOTAL ASS'Y 1000 2000 3000 4000 5000 ¡ ¡ ¡ ¡ ¡ CAPSTAN MOTOR ¡ L/C BRKT TOTAL ASS'Y REEL BELT IDLER PLATE TOTAL ASS'Y REEL TABLE T SUB BRAKE ASS'Y TENSION BAND ASS'Y S MAIN BRAKE ASS'Y T MAIN BRAKE ASS'Y PINCH ROLLER ASS'Y AC HEAD ASS'Y FE HEAD REEL GEAR TOTAL ASS'Y : Check and Replace if necessary.
2-3. JIGS AND TOOLS 2-3-1) LIST OF JIGS AND TOOLS ITEMS 1 ALIGNMENT TAPE 2 CLEANING TAPE (DAEWOO) DHC-602V CHECKING OF THE TAPE TRANSPORTING SYSTEM 3 CASSETTE TAPE (KOKUSAI) KT-300NV KT-300RV MEASUREMENT OF REEL TORQUE 4 VHS SPINDLE HEIGHT GAUGE TSH-V4 MEASUREMENT OF REEL HEIGHT 5 TENTELO METER (TENTELO) T2-H7-UM MEASUREMENT OF THE BACK TENSION 6 FAN TYPE TENSION METER 7 DENTAL MIRROR 8 MODEL FIG.
2-3-2) SKETCH OF JIGS AND TOOLS CLE ANI NG TAP E TAP E 30 11 8-2 0 30 10 8-1 VHS SPINDLE HEIGHT GAUGE 0 10 10 30 20 20 20 30 ALI GN ME NT 10 8-3 20
3. DISASSEMBLY AND REPLACEMENT 3-1. FRONT LOADING ASS'Y REMOVAL (See Fig. 3-1) NOTE: The FRONT LOADING ASSEMBLY can be removed only in the eject position. a. Remove 2 screws fixing the Front Loading ASS'Y. b. Lift the rear of the front loading assembly to separate it from the Main Base. AF002 Fig.
3-2. DISASSEMBLY OF THE FRONT LOADING ASS'Y (See Fig. 3-2~3-6) a. Remove one screw holding the F/L BRACKET R and move the F/L BRACKET R in the direction of arrow to separate it from the TOP PLATE and CASSETTE HOLDER ASSEMBLY. b. Remove the CASSETTE HOLDER ASSEMBLY. (Fig. 3-2) c. Remove one screw holding the PRISM LINK R and remove the PRISM LINK R from the F/L BRACKET R. (Fig.
d. Remove one screw holding the PRISM LINK L. (Fig. 3-4) e. Release the hook B by pushing it in the direction of the arrow and remove the DOOR OPENER. (Fig. 3-4) f. Remove the LOADING LEVER ASSEMBLY by pressing the connected section of the loading lever assembly in the directions of the arrows. (Fig. 3-5) g. Remove the SAFETY SPRING between the SAFETY LEVER and the CASSETTE HOLDER PLATE. (Fig. 3-5) h. Remove the RELEASE SPRING between the RELEASE LEVER and the SAFETY LEVER R. (Fig.
NOTE: Reassemble the FRONT LOADING MECHANISM in the reverse order. Confirm that the two bosses on the left side of the CASSETTE HOLDER AS are inserted into the groove on the left side of the top plate. Insert the two bosses on the right side of the cassette holder into the groove of the F/L BRAKCET R (Fig. 3-6) TOP PLATE INSERT POINTS 3-3. DRUM ASS'Y/EARTH BRACKET ASS'Y REMOVAL (See Fig.3-7) a. Remove three screws fixing the DRUM TOTAL ASSEMBLY. b.
3-4. REEL BELT, LOADING RACK ASS'Y, LOADING ASS'Y, S/T SLANT POLE ASS'Y REMOVAL (See Fig.3-8) a. Turn over the DECK MECHANISM and remove the REEL BELT . b. Remove one POLY WASHER . c. Remove the LOADING RACK ASS'Y . d. Remove R & L LOADING ASS'YS and . e. Remove the S and T SLANT POLES and by pulling them in the directions of the arrows. CAUTION: Take care not to get the GUIDE ROLLERS of the S/T SLANT POLES stained with GREASE When reassembling, refer to Fig.
3-5. A/C HEAD ASS'Y REMOVAL (See Fig.3-10) a. Remove one nut hex from the A/C HEAD POST of the MAINBASE. b. Remove the A/C HEAD ASSEMBLY from the MAINBASE. c. Remove the A/C HEAD SPRING from the A/C HEAD ASSEMBLY . NOTE: After reassembling, adjust the TAPE TRANSPORTING SYSTEM refering to chapter 5 "ADJUSTMENT OF THE TAPE TRANSPORTING SYSTEM". After adjusting the TAPE TRANSPORTING SYSTEM, spread the A/C HEAD/NUT, AZIMUTH SCREW, and TILT SCREW with LOCKING PAINT. 3-6. L/C BRACKET ASS'Y REMOVAL (See Fig.
3-8. CAM GEAR, RELAY LEVER AND F/L RACK REMOVAL (See Fig.3-11) a. Remove the CAM GEAR from the MAINBASE. (Fig.3-11) b. Remove the RELAY LEVER from the MAINBASE. (Fig. 3-11) c. Remove the F/L RACK from the MAINBASE by pulling it in the direction of the arrow. NOTE: When reassembling, refer to Fig. 3-12, 13. 3-9. S/T MAIN & SUB BRAKE ASS'Y REMOVAL (See Fig.3-14) a. Remove the S, T MAIN BRAKE Assembly from the MAIN VASE b.
3-10. TENSION BAND ASS'Y REMOVAL (See Fig.3-15, 3-16) a. Remove the TENSION SPRING from the MAINBASE . (Fig.3-15) b. Turn the DECK MECHANISM over. (Fig.3-16) c. After separating the tab of hook 'A', remove the TENSION BAND ASSEMBLY . (Fig.3-16) NOTE: After assembling the TENSION BAND ASSEMBLY on the MAINBASE, adjust the position of TENSION POLE as shown Fig. 3-17. Avoid getting GREASE, OIL or foreign substance on the FELT of the BAND BRAKE. Take care not to deform tab 'A' when separating it .
3-11. CAPSTAN MOTOR REMOVAL (See Fig.3-18) Remove 3 screws fixing the CAPSTAN MOTOR and separate the CAPSTAN MOTOR. 3-12. IDLER PLATE TOTAL ASS'Y & S/T REEL TABLE REMOVAL (See Fig.3-19) a. Remove one POLY WASHER from the REEL GEAR POST and remove the IDLER PLATE TOTAL ASSEMBLY from the MAIN BASE. b. Remove the S/T REEL TABLES and two POLY SLIDERS from the DECK MECHANISM. CAUTION: When disassembling or assembling the IDLER PLATE TOTAL ASSEMBLY, take care not to bend it.
3-13. FE HEAD REMOVAL (See Fig.3-20) Remove one screw fixing the FE HEAD and remove the FE HEAD from the MAINBASE. 3-14. REEL GEAR TOTAL ASS'Y & CONNECT PLATE REMOVAL (Fig.3-21) a. Turn over the DECK MECHANISM and remove one POLY WASHER from the REEL GEAR POST . b. After separating tab 'B' of the MAINBASE, remove the REEL GEAR TOTAL ASSEMBLY from the MAINBASE. c. Remove the CONNECT PLATE from the MAINBASE by pushing it in the direction of the arrow.
4. MECHANICALADJUSTMENT 4-1. MECHANICAL ADJUSTMENT (See Fig.4-1~4-5) When operational problems occur or the mechanism is reassembled, be sure to confirm the following INSTRUCTIONS. a. Make sure that the DATUM HOLE of the CAM GEAR is aligned with the DATUM HOLE in the MAINBASE in the EJECT mode, as shown in Fig.4-1. CAM GEAR DATUM HOLE OF CAM GEAR DATUM HOLE OF MAIN BASE F/L RACK b.
c. When reassembling the L/C BRACKET TOTAL ASSEMBLY on the MAINBASE, make sure that the two triangular marks of CAM SWITCH are aligned with each other as shown in Fig.4-3. TRIANGLE MARKS MUST MEET EACH OTHER d. Make sure that boss "A" of the PINCH LEVER TOTAL ASSEMBLY is positioned at point "B" of the CAM GEAR, as shown in Fig.4-4.
e. Make sure that the triangular mark "A" on the L LOADING ASSEMBLY is aligned with the notch "B" on the R LOADING ASSEMBLY as shown in Fig. 4-5. f. Make sure that the teeth of the LOADING RACK ASSEMBLY are aligned with those of the R LOADING ASSEMBLY so that the hole of the LOADING RACK ASSEMBLY aligns with the circular mark on the R LOADING ASSEMBLY, as shown in Fig.4-5.
4-2. BACK TENSION MEASUREMENT (See Fig.4-6~4-7) a. Confirm that the position of the TENSION POLE is correctly POSITIONED. Refer to the "4-4 TENSION POLE POSITION ADJUSTMENT ". b. Play back a T-120 TAPE at its center position without assemblying F/L ASSEMBLY and wait until the TAPE running is stabilized (about 5~10 seconds). c. Bring the TENTELOMETER into contact with the TAPE (Fig.4-6) and measure the BACK TENSION. The measuring result should be between 25 and 33 grams. d.
4-3. MECHANICAL MODE (OPERATING THE VCRWITHOUT A CASSETTE TAPE) a. Remove the FRONT LOADING MECHANISM from the DECK MECHANISM. b. Pull the F/L RACK. c. The S/T POLE BASES are loaded and PLAY BACK MODE starts. d. Turn off the power when the MECHANISM is in the desired position. 4-4. TENSION POLE POSITION ADJUSTMENT a. MAKE MECHANICAL MODE be PLAY MODE. Refer to "4-3 MECHANICAL MODE". b. Confirm that the datum hole of TENSION LEVER is aligned with the datum hole of the MAIN BASE. c.
5. ADJUSTMENTOFTAPETRANSPORTINGSYSTEM Generally the TAPE TRANSPORTING SYSTEM has been precisely adjusted in the factory and does not ordinarily require readjustment. But when noise and tape damage take place and part assemblies that compose the TAPE TRANSPORTING SYSTEM are replaced, check and readjust the TAPE TRANSPORTING SYSTEM. Refer to the following FLOW CHART in order to adjust the TAPE TRANSPORTING SYSTEM.
Fig. 5-1 THE SCHEMATIC DIAGRAM OF TAPE TRANSPORTING SYSTEM When the parts as shown in Fig. 5-1 are replaced, the TAPE TRANSPORTING SYSTEM has changed. To prevent this, it is essential to know thoroughly and observe the following INSTRUCTIONS. A. ADJUSTMENT OF THE S/T GUIDE ROLLER a. Play back a T-120 TAPE. b. Make sure that excessive TAPE wrinkle does not occur at each S/T GUIDE ROLLER. c. If TAPE wrinkle is observed at the S/T GUIDE ROLLER, adjust them so that no wrinkle occurs.
B. ADJUSTMENT OF THE A/C HEAD ASS'Y (TILT ADJUSTMENT) a. Play back a T-120 Tape and check the running condition of the TAPE at the lower flanges of the T GUIDE POST ASS'Y ¤æin Fig. 5-1. b. Adjust the A/C HEAD TILT SCREW untill the TAPE runs stable as shown in Fig. 5-2 TURN THE A/C HEAD TILT SCREW TO THE DIRECTION OF CW ( ( ) ) TURN THE A/C HEAD TILT SCREW TO THE DIRECTION OF CCW Fig. 5-2 A/C HEAD ASS'Y ADJUSTMENT (TILT ADJUSTMENT) C. ADJUSTMENT OF THE AUDIO AZIMUTH (See Fig.5-3) a.
E. X-POSITION ADJUSTMENT S/W PULSE TEST PIN PATH ADJ. FIXTURE ENVELOPE TEST PIN PATH ADJ. FIXTURE TEST POINTS MEASURING EQUIPMENT OSCILLOSCOPE VR CONTROL PATH ADJ. FIXTURE ADJUST BOSS MAIN BASE. ADJUSTMENT a. Connect the path adjustment fixture to PT01 of the MAIN CIRCUIT BOARD. b. Play back the ALIGNMENT TAPE (COLOR BAR ALIGNMENT). c. Connect channel-1 scope probe to S/W PULSE TEST PIN of PATH ADJ, FIXTURE. d. Connect channel-2 scope probe to ENVELOPE TEST PIN of PATH ADJ, FIXTURE. e.
F. PLAYBACK PHASE ADJUSTMENT (See Fig. 5-6) S/W PULSE TEST PIN PATH ADJ. FIXTURE VIDEO OUT MAIN CIRCUIT BOARD TEST POINTS MEASURING EQUIPMENT OSCILLOSCOPE ADJUSTMENT VR595 (PG SHIFTER) MAIN CIRCUIT BOARD Phase generator (PG) shifter decides the VIDEO HEAD switching point when a TAPE is played back. In case the Phase generator (PG) shifter isn't correctly tuned, HEAD switching noise or vertical jitter may occur. a. Connect the PATH ADJ. FIXTURE to PT01 of the MAIN CIRCUIT BOARD. b.
G. LINEARITY ADJUSTMENT S/W PULSE TEST PIN PATH ADJ. FIXTURE ENVELOPE TEST PIN PATH ADJ. FIXTURE TEST POINTS MEASURING EQUIPMENT OSCILLOSCOPE VR CONTROL PATH ADJ. FIXTURE S/T GUIDE ROLLER TAPE TRANSPORTING SYSTEM ADJUSTMENT a. Connect the PATH ADJ. FIXTURE to PT01 of the MAIN CIRCUIT BOARD. b. Play back the ALIGNMENT TAPE (COLOR BAR SIGNAL). c. Connect the channel-1 scope probe to the S/W PULSE TEST PIN of the PATH ADJ. FIXTURE. d.
H. DRUM ENTRANCE /EXIT (See Fig. 5-8, 5-9) S/W PULSE TEST PIN PATH ADJ. FIXTURE ENVELOPE TEST PIN PATH ADJ. FIXTURE TEST POINTS MEASURING EQUIPMENT OSCILLOSCOPE VR CONTROL PATH ADJ. FIXTURE S/T GUIDE ROLLER TAPE TRANSPORTING SYSTEM ADJUSTMENT a. Connect the PATH ADJ. FIXTURE to PT01 the MAIN CIRCUIT BOARD. b. Play back the ALIGNMENT TAPE (COLOR BAR SIGNAL). c. Connect the channel-1 scope probe to the S/W PULSE TEST PIN of the PATH ADJ. FIXTURE. d.
I. REVIEW ¤ APLAY (See Fig. 5-10) S/W PULSE TEST PIN PATH ADJ. FIXTURE ENVELOPE TEST PIN PATH ADJ. FIXTURE TEST POINTS MEASURING EQUIPMENT OSCILLOSCOPE VR CONTROL PATH ADJ. FIXTURE S/T GUIDE ROLLER TAPE TRANSPORTIN SYSTEM ADJUSTMENT a. Connect the PATH ADJ. FIXTURE to PT01 of the MAIN CIRCUIT BOARD. b. Play back the ALIGNMENT TAPE (SP, COLOR BAR SIGNAL). c. Connect the channel-1 scope probe to the S/W PULSE TEST PIN of the PATH ADJ. FIXTURE. d.
J. AUDIO OUTPUT (A/C HEAD TILT & HEIGHT ADJUSTMENT) TEST POINTS AUDIO OUTPUT MEASURING EQUIPMENT OSCILLOSCOPE AUDIO OUTPUT JACK a. Connect the OSCILLOSCOPE to the AUDIO OUTPUT JACK. b. Play back the ALIGNMENT TAPE (NTSC: DN1 (SP, 1KHz), PAL: DP1 (SP, 1KHz)). c. Check the AUDIO OUTPUT SIGNAL is -9~-3dBm. d. If the requirement "c" is not satisfied, adjust the A/C HEAD TILT SCREW and A/C HEAD HEIGHT NUT to obtain the maximum audio output. (Fig. 5-3) K. A/C HEAD AZIMUTH ADJUSTMENT a.
L. X-POSITION (See Fig. 5-11) S/W PULSE TEST PIN PATH ADJ. FIXTURE ENVELOPE TEST PIN PATH ADJ. FIXTURE TEST POINTS MEASURING EQUIPMENT OSCILLOSCOPE VR CONTROL PATH ADJ. FIXTURE ADJUST BOSS MAIN BASE. ADJUSTMENT a. Connect the PATH ADJ. FIXTURE to PT01 of the MAIN CIRCUIT BOARD. b. Play back the ALIGNMENT TAPE (COLOR SIGNAL BAR). c. Connect the channel-1 scope probe to the S/W PULSE TEST PIN of the of the PATH ADJ. FIXTURE. d.
6. EXPLODED VIEW AND PARTS LIST 6-1.
6-2.
6-3.
D0040 D0020 D0040 D0050 D0010 D0060 D0070 D0080 D0090 40
6-4-1. PARTS LIST OF DECK TOTAL ASS'Y LOC. NTSC M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO PAL M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO PAL M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO M1OOO STOCK NO.
LOC. STOCK NO.
6-4-2. PARTS LIST OF DRUM PRICE ASS’Y LOC. STOCK NO.
6-4-3.PARTS LIST OF DRUM TOTAL ASS’Y LOC. STOCK NO.
LOC. STOCK NO. PART NAME DESCRIPTION A2000 7274300611 SCREW TAPPTITE TT3 RND 3X6 MFZN K30,K50 A2100 97SA311620 IDLER PLATE AS K30-MECHA(HI-REW) K30 A2100 97SA311600 IDLER PLATE AS K50-MECHA(NORMAL) K50 A2200 97S3108200 POLYWASHER D2.6XD6.0XT0.5 K30,K50 A2300 97S2901600 TABLE REEL F20 BLACK K30,K50 A2400 97S3903600 POLY SLIDER D3.1XD6XT0.5 K30,K50 A2500 A2600 97SA310800 97S3003500 TENSION BAND AS SPG TENSION K-MECHA SWPB D0.
DAEWOO ELECTRONICS CO., LTD 686, AHYEON-DONG MAPO-GU SEOUL, KOREA C.P.O. BOX 8003 SEOUL, KOREA TELEX : DWELEC K28177-8 CABLE : "DAEWOOELEC" E-mail : G7F00E@web.dwe.co.
