RCA-RTD300-cs-sm 维修电路原理图.pdf

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1、3.1Removal of the FRONT LOADING Assy (Fig. 3.1)a. Unscrew the 2 screw holding the F/L.b. Separate the F/L ASSY from the MAIN BASE settlingdown point by lifting the rear part of F/L(Screw hole).3.2 Disassembly of FRONT LOADING Assy (FIg. 3.23.5)a. Remove the one WASHER for holding the door openerand

2、separtate F/L Assembly by moving the DOOROPENER in the direction of arrow.b. Remove the 2 screw holding the TOP PLATE and sepa-rate the CASSETT HOLDER ASSY by moving the FL BRKT L and FL BRKT R in the direction of arrow(Fig. 3.2)3. DISASSEMBLY AND REPLACEMENTNOTE:REMOVE THE FRONT LOADING ASSY IN EJE

3、CTMODEFig. 3.1 Diassembly of the FRONT LOADING ASSYFig. 3.2 Diassembly of the FRONT LOADING ASSY RadioFans.CN 收音机爱 好者资料库c. Separate the LOADING LEVER ASSY by pressingthe connection point from the CASSETTE HOLDERASSY.(Fig. 3.3)d. Remove the SAFETY SPRING connecting the SAFETYLEVER and CASSETTE HOLDER

4、 PLATE.(Fig. 3.3)e. Remove the RELEASE SPRING connecting theRELEASE LEVER and SAFETY LEVER.(Fig3.3)3. 3 Disassembly of DRUM Assy (Fig. 3.5)a. Turn over the DECK MECHANISM and holding theDRUM TOTAL ASSY with hands , remove the 3screw holding the drum total assembly with main base.b. Separatet the DRU

5、M TOTAL ASSY from the deck pay-ing attention there is no damage on the surface of VIDEOHEAD and DRUM. c. Assembly step is the reverse way of diassembly.DISASSEMBLY AND REPLACEMENT (CONTINUED)CAUTION:Assemble the FRONT LOADING ASSY in the reversestep of diassembly. Confirm that two bosses on the left

6、side of the CASSETTE HOLDER ASSY are inserted inthe groove on the left side of the top plate. Insert twobosses on the right side of the CASSETTE HOLDERASSY into the groove of the F/L BRACKET R.(Fig. 3.4)FIg. 3.3 Disassembly of the CASSETTE HOLDER AssyFIg. 3.4 Assembly of the FL AssyCAUTION: After th

7、e assembly of the DRUM TOTAL ASSY,check out if DECK mecahnism operate smoothly andadjustment of tape transmission section is OK.FIg. 3.5 Diassembly of DRUM ASSYRadioFans.CN 收音机爱 好者资料库3. 4. Disassembly of LOADING RACK, LOADING ASSY, S/T SLANT POLE ASSY (Fig. 3.6, 3.7)a. Turn out the DECK MECHANISM an

8、d remove theLOADING RACK after unscrewing the SCREW .b. Disintegrate the R LOADING AS # and L LOADINGAS $ .c. Disintegrate the S SLANT POLE AS %and T SLANTPOLE AS by moving those part in arrow dircetion.3. 5. Disassembly of the A/C HEAD ASSY (Fig. 3.8)a. Remove the CONNECTOR from the AC HEADASSY, Wa

9、tch out that there is no damage in the HEADconnecting PIN.b. Separate the AC HEAD ASSY !after unscrewing the-screw #DISASSEMBLY AND REPLACEMENT (CONTINUED)CAUTION: Take care GUIDE ROLLER of S/T SLANT POLE ASand SLANT POLE not to be stained with grease duringassembly. Refer to Fig. 3.7 in assembly.FI

10、g. 3.6 Disassembly of the LOADING RACK, LOADINGASSY and the SLANT POLE ASSYFIg. 3.7 Assembly of the L/R LOADING AS and theLOADING RACKCAUTION: After the assembly, adjust the tape transmissionsec-tion by refering to the chapter 5. After the adjustment of the tape transmission section,paint the 3 adju

11、stment screw with locking paint.FIg. 3.8 Disassembly of the AC HEAD ASSY3. 6. Disassembly of the LC BRKT ASSY, PINCH LEVER TOTAL ASSY (Fig. 3.9)a. Separate the LC BRKT Assy after removing the 3screws !.b. Separate the LC BRKT Assy from the DECKMECHANISM.c. Disintegrate the PINCH LEVER TOTAL Assy #.3

12、. 7. Disassembly of the CAM GEAR, RELAYLEVER, FL RACK (Fig. 3.9)a. Separate the CAM GEAR %from the MAINBASE.b. Separate the RELAY LEVER from the MAINBASE.c. Separate the FL RACK &from MAINBASE by movingto the arrow direction.DISASSEMBLY AND REPLACEMENT (CONTINUED)CAUTION: After the assembly of the P

13、INCH LEVER TOTALAssy, adjust the tape transmission section by refering tothe chapter 5. There should be no pollution on the surface ofPINCH ROLLER $ with grease or other foreignmaterial. Make sure if the end of the PINCH SPRINGPINCH“A” is located at the end of trajectory of CAM GEAR“B” in assembly (

14、Refer to Fig. 4.3)CAUTION: When reassembling, refer to Fig. 3.10, Fig. 3.11 andchapter 4.FIg. 3.9 Disassembly of the LC BRACKET ASSY fromthe PINCH LEVER TOTAL ASSYFIg. 3.10 Assembly of the CAM GEAR, RELAY LEVERFIg. 3.11 Assembly of the CAM GEAR, FL RACK3. 8 Disassembly of the S/T BRAKE ASSY(Fig. 3.1

15、2)a. Unhook the S BRAKE SPRING #from the MAIN-BASE HOOK !.b. Remove the S BRAKE Assy from the mainbase.c. Remove the T BRAKE SPRING from the MAIN-BASE HOOK $.d. Remove the T BRAKE Assy %.3. 9 Disassembly of the TENSION BAND ASSY(Fig. 3.13)a. Unhook the TENSION SPRING from the MAIN-BASE HOOK !.b. Unh

16、ook the MAINBASE HOOK “A” and remove theTENSION BAND Assy #from the mainbase.3. 10 Disassembly of the Capstan Motor (Fig. 3.13)a. Separate the CAPSTAN MOTOR %after the removal of3 screws $holding the capstan motor.3.11 Disassembly of the FE HEAD (Fig. 3.13)a. Remove the screw and separate the FE HEA

17、D &fromthe MAINBASE.DISASSEMBLY AND REPLACEMENT (CONTINUED)CAUTION: After the assembly of TENSION BAND Assy on themainbase, adjust the TENSION POLE location asshown in Fig. 3.14. Avoid getting Grease, Oil or Foreign substance on theFELT of the BAND BRAKE. Take care not to deform the MAINBASE HOOK “A

18、”when separating the TENSION BAND Assy #.FIg. 3.12 Disassembly of the S/T BRAKE ASSYFIg. 3.13 Disassembly of the TENSION BAND ASSY,CAPSTAN MOTOR and the FE HEADFIg. 3.14 Adjustment of the TENSION POLE POSITION3.12 Disassembly of the REEL TABLE, IDLER PLATE TOTAL ASSY (Fig. 3.15)a. Remove the POLY WA

19、SHER !and separate theIDLER PLATE TOTAL Assy from the mainbase.b. Remove the REEL TABLE $from the REEL TABLEPOST #of the MAINBASE.3.13 Disassembly of the REEL BRKT TOTALASSY, CONNECT PLATE (Fig. 3.16)a. Turn over the DECK MECHANISM and remove 2screws !.b. Remove the REEL BRKT TOTAL Assy from theMAIN

20、BASE.c. Separate the CONNECT PLATE #from the MAIN-BASE by pushing to the direction of the arrow.DISASSEMBLY AND REPLACEMENT (CONTINUED)CAUTION: Take care not to deform the IDLER PLATE TOTALAssy when assembling and disassembling.CAUTION: In diassembly of the REEL BRKT TOTAL ASSY,take care REEL BELT a

21、nd REEL FELT not to bestained with GREASE, OIL, or foreign substance. diassembly of the IDLER ASSY should be precedethe diassembly of the REEL BRKT TOTAL ASSY. Check the operation of the REEL BRKT TOTALASSY before assembly. Check the operation of FF/REW, PLAY, CUE, andREVIEW work well and existence

22、of noise duringthe mode operation.FIg. 3.15 Disassembly of the REEL TABLE and the IDLERPLATE TOTAL ASSYFIg. 3.16 Disassembly of the REEL BRKT TOTAL ASSYand the CONNECT PLATE6.1 Exploded view of DECK Assy ( Top View)6. EXPLODED VIEW 6. 2 Exploded view of DECK Assy ( Bottom View)EXPLODED VIEW (CONTINU

23、ED)6.3 Exploded view of FL AssyEXPLODED VIEW (CONTINUED)D0040D0040D0020D0050D0010D0060D00702.1.Assembly diagram2.1.1.DECK Assembly diagramA. Upper View2. ASSEMBLY DIAGRAM AND A/S1MAIN BASE ASSY2DRUM ASSY3FE HEAD4S SLANT POLE ASSY5TENSION BAND ASSY6S BRAKE ASSY7REEL TABLE8REEL BRKT TOTAL ASSY9IDLER P

24、LATE TOTAL ASSY10 T BRAKE ASSY11 FL RACK12 RELAY LEVER13 CAPSTAN MOTOR14 LC BRKT ASSY15 PINCH LEVER TOTAL ASSY16 CAM GEAR17 AC HEAD ASSY18 T SLANT POLE ASSY19 LOADING RACK20 L LOADING ASSY21 R LOADING ASSY22 CONNECT PLATE23 REEL BELT24 CABLE FFCASSEMBLY DIAGRAM AND A/S(CONTINUED)B. Lower View1MAIN B

25、ASE ASSY2DRUM ASSY3FE HEAD4S SLANT POLE ASSY5TENSION BAND ASSY6S BRAKE ASSY7REEL TABLE8REEL BRKT TOTAL ASSY9IDLER PLATE TOTAL ASSY10 T BRAKE ASSY11 FL RACK12 RELAY LEVER13 CAPSTAN MOTOR14 LC BRKT ASSY15 PINCH LEVER TOTAL ASSY16 CAM GEAR17 AC HEAD ASSY18 T SLANT POLE ASSY19 LOADING RACK20 L LOADING A

26、SSY21 R LOADING ASSY22 CONNECT PLATE23 REEL BELT24 CABLE FFCASSEMBLY DIAGRAM AND A/S(CONTINUED)2.1.2.FRONT LOADING Assembly diagram1FL BRKT L2TOP PLATE3SAFETY LEVER4LOADING LEVER AS45CST HOLDER AS6DOOR OPENER7SAFETY LEVER R8FL BRKT RFig.24. 1 Mechanical Adjustment (Fig. 4.14.4)In case of diassembly

27、and reassembly for fixing the mecanicalproblem, check the following check point.a. Make sure that the DATUM HOLE of the CAM GEAR isaligned wth the DATUM HOLE in the MAINBASE inthe EJECT mode as shown in Fig. 4-1.b. Make sure that the ending part “A” of the RELAYLEVER assembled on the CONNECT PLATE i

28、s alignedwith the reference hole “B” of the MAINBASE as shownin Fig. 4.2.c. The end point “A” of PINCH SPRING PIN of theLEVER TOTAL ASSY should be located within thetrajectory “B” of the CAM GEAR. (Fig. 4.3)4. MECHANICAL ADJUSTMENTFIg. 4.1 Assembly reference between the FL RACK and theCAM GEARTURN T

29、O THE ENDALIGNFIg. 4.2 Assembly reference between the RELAY LEVERand the CAM GEARFIg. 4.3 Assembly reference of the PINCH LEVER TOTALASSYwith the CAM GEARd. Make sure that the triangular mark “A” of the L LOAD-ING Assy is aligned with the mark “b” of the R LOAD-ING Assy. (Fig. 4.4)e. Reference hole

30、“C” of the LOADING RACK should bealigned with the reference hole of the R LOADING Assyto make the teeth of the LOADING RACK is aligned asshown in Fig. 4.4.4. 2 Adjustment and measurement of the BACK TENSION (Fig. 4.5, 4.6)a. Check that the location of the TENSION POLE is in theright position. if not

31、, adjust that by refering to the “4.4Adjustment of the TENSION POLE position”.b. Play back the T-120 TAPE in S-MAX for 20seconds.(Generally tape transporting section is settleddown in 20 seconds)c. Measure the BACK TENSION by using the TENTELOMETER (Refer Fig 4.5) The result should be within therang

32、e of 20g 30g.d. If the BACK TENSION is out of the range, change theposition of the TENSION SPRING of repeat theprocess of “4.4 Adjustment of the TENSION POLEposition”.(Fig. 4.6)MECHANICAL ADJUSTMENT (CONTINUED)FIg. 4.4 Assembly reference between the LOADING RACKand the LOADING LEVER ASSYCAUTION: If

33、the measurement result greater than the upper limit,change the hook point of the spring to position “A” Confirm that all of the three probes of TENTELOMETER are in contect with the tape. During measuring, dont touch any other parts of theMECHANISM(i.e. MAINBASE). It is recommend-ed that this measurm

34、ent be repeated at least threetimes for an accurate reading.FIg. 4.5 Measurement of the BACK TENSION4. 3 Mechanical Mode (Operate without a cassette tape)a. Remove the FRONT LOADING MECHANISM from theDECK MECHANISMb. Cap the IR LED and pull the FL RACK. This has the sameeffect with cassette loading

35、to the deck.c. If the S,T POLE BASE is loaded, PLAY MODE startsautomatically. If you want other function, press the cor-responding button.d. Turn off the power when the Mechanism is in the desiredposition.4. 4 Adjustment of the position of the TENSION POLE (Fig. 4.6)a. Place the MECHANICAL MODE in t

36、he PLAY MODE.Refer to the above section “4.3 MECHANICAL MODE”b. Confirm that the TENSION LEVER is aligned with thedatum hole of the MAINBASE.c. If the requirement “b” is not satisfied. turn the BANDBRAKE ADJUST CAP clockwise or counterclockwiseuntil the two datum holes aligns with each other.MECHANI

37、CAL ADJUSTMENT (CONTINUED)FIg. 4.6 Adjustment of the TENSION POLE POSITION5. ADJUSTMENT OF THE TAPE TRANSPORT SECTION.Generally, tape transporting section has been precisely adjusted in the factory and does not require the ordinary readjustment.But there is the case that tape noise or impact on the

38、deck mechanism, tape transporting section readjustment is required. Inadjustment of the tape transmission section consut the following flow chart. If any components shown in Fig. 5.1, tape transport section are changed. To readjust the tape transporting section.FIg.5.1 A schematic diagram of the tap

39、e transport ing section.S/T GUIDE ROLLER HEIGHTADJUSTMENTDRUM TOTAL AS A/C HEAD AS PINCH LEVER TOTAL AS S/T GUIDE ROLLER FLUNGEA/C HEAD AS ADJUSTMENT (TILT ADJUSTMENT)CLEANINGAUDIO AZIMUTH ADJUSTMENTA/C HEAD ADJUSTMENTX-POSITION ADJUSTMENTPLAYBACK PHASE ADJUSTMENTLINEARITY ADJUSTMENTDRUM ENTRANCE/EX

40、IT ENVELOPE FINE TUNINGREVIEWPLAY CHANGING OPERATION CHECKAUDIO AZIMUTH ADJUSTMENTAUDIO OUTPUT CHECK (A/C HEAD HEIGHT& TILT ADJUSTMENT)X-POSITION ADJUSTMENTTRACKINGS SLANT PLOE AS T SLANT POLE AS TENSION BAND ASTable.1 Adjustment Flow Diagram of the Tape Transporting SystemA. Adjustment of the S/T G

41、UIDE ROLLERA. Adjustment of the S/T GUIDE ROLLERa. Check the Playing back with a T-120 TAPE.b. Make sure that excessive tape wrinkle does not occureateatch S, T GUIDE ROLLER.c. If tape wrinkle is observed at the S/T GUIDE ROLLER,turn the guide roller screw until there is not tape wrinkle.B.Adjustmen

42、t of the AC HEAD ASSY(TILT)a. Play back a T-120 TAPE and check the running status oflower side of GUIDE POST.b. If there is any problem, Turn the AC HEAD TILTSCREW until the running status improved. (Fig. 5.2)C.Adjustment of the AC HEAD Height(Fig. 5.3)a. Play back a T-120 TAPE.b. Make sure that the

43、 gap between the lower end of TAPEand the AC head is 0.25m.c. If the measurement of the gap is different from the refer-ence value 0.25mm, turn the screw ! , # until thedesired gap is obtained.D.Adjustment of the AUDIO AZIMUTH(Fig. 5.4)a. Play back the ALIGNMENT TAPE(DN2 : SP, NTSC,7KHz)b. Check the

44、 AUDIO output with a AUDIO LEVELMETER.c. Turn the AC HEAD AZIMUTH SCREW until themaximum AUDIO output(-9dBm -3dBm)is obtained.E.Adjustment of the X-POSITION(Fig. 5.4 5.5)a. Connect the PATH ADJ. FIXTURE to the PT01 on theMAIN CIRCUIT BOARD.b. Play back the ALIGNMENT TAPE (DN2 : SP MONO-SCOPE).c. Con

45、nect the S/W pin and ENVE pin of the PATH ADJ.FIXTURE with the SCOPE PROBE.d. Insert the adjustment bar in the AC HEAD ADJUST hole$and adjust the X-POSITION of the AC HEADASSY until the ENVE is maximum when the VR is onthe CENTER. There is the possibility that an another TRACKING CEN-TER can be occu

46、r when the AC HEAD ASSY turnedcompletely in the counterclockwise direction, Hence adjustthe X-position with AC HEAD ASSY adhering closelyto the right side until the maximum ENVE is obtained.e. The adjustment of the X-POSITION finished, checkif the AUDIO LEVEL is degraded, then readjustmentof the AUD

47、IO AZIMUTH is required.ADJUSTMENT OF THE TAPE TRANSPORT SECTION. (CONTINUED)FIg.5.2 Adjustment of the AC HEAD ASSYFIg.5.3 Adjustment of AC HEAD HeightFIg.5.4 Adjustment of AUDIO AZIMUTH, X-POSITION S/W PULSE TEST PINPATH ADJ. FIXTUREENVELOPE TEST PINPATH ADJ.FIXTUREMeasurement Equipment OSILLOSCOPEV

48、R CONTROLPATH ADJ.FIXTUREAC HEAD ADJUST HOLEADJUSTMENT BARTest PointAdjustmentF. PLAYBACK PHASE ADJUSTMENT(Fig. 5.6)PHASE GENERATOR(PG) SHIFTER determine theVIDEO HEAD SWITCHING POINT when the TAPE isplayed back. If an adjustment of the PHASE GENERA-TOR(PG) SHIFTER is not done precisely, There can b

49、e aHEAD SWITCHING NOISE or a VERTICAL JITTERproblem, vibration of the picture on the screen, not goodquality of picture in special play back.a. Connect the PT01 on the MAIN CIRCUIT BOARD witha PATH ADJ. FIXTURE.b. Play back an ALIGNMENT TAPE(DN-2 : MON-SCOPE sig-nal)c. Connect the S/W PULSE TEST PIN

50、 on the PATH ADJ.FIXTURE with a CHANNEL-1 SCOPE PROBE.d. Connect the VIDEO OUT on the MAIN CIRCUITBOARD with a CHANNEL-2 SCOPE PROBE (1V/div).e. Control the PG VOLUME until the time intervalbetween the SWITCHING PULSE and the V-SYNCSIGNAL is within the 6.5H0.5H as shown in Fig. 5.6.G.Adjustment of t