RCA-RTD300-cs-sm 电路图 维修手册.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 settling down 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 opene

2、r and separtate F/L Assembly by moving the DOOR OPENER 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 REPLACEMENT NOTE: REMOVE THE FRONT LOADIN

3、G ASSY IN EJECT MODE Fig. 3.1 Diassembly of the FRONT LOADING ASSY Fig. 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 pressing the connection point from the CASSETTE HOLDER ASSY.(Fig. 3.3) d. Remove the SAFETY SPRING connecting the SAFETY LEVE

4、R and CASSETTE HOLDER PLATE.(Fig. 3.3) e. Remove the RELEASE SPRING connecting the RELEASE LEVER and SAFETY LEVER.(Fig3.3) 3. 3 Disassembly of DRUM Assy (Fig. 3.5) a. Turn over the DECK MECHANISM and holding the DRUM TOTAL ASSY with hands , remove the 3 screw holding the drum total assembly with mai

5、n base. b. Separatet the DRUM TOTAL ASSY from the deck pay- ing attention there is no damage on the surface of VIDEO HEAD and DRUM. c. Assembly step is the reverse way of diassembly. DISASSEMBLY AND REPLACEMENT (CONTINUED) CAUTION: Assemble the FRONT LOADING ASSY in the reverse step of diassembly. C

6、onfirm that two bosses on the left side of the CASSETTE HOLDER ASSY are inserted in the groove on the left side of the top plate. Insert two bosses on the right side of the CASSETTE HOLDER ASSY into the groove of the F/L BRACKET R.(Fig. 3.4) FIg. 3.3 Disassembly of the CASSETTE HOLDER Assy FIg. 3.4

7、Assembly of the FL Assy CAUTION: After the assembly of the DRUM TOTAL ASSY, check out if DECK mecahnism operate smoothly and adjustment of tape transmission section is OK. FIg. 3.5 Diassembly of DRUM ASSY RadioFans.CN 收音机爱 好者资料库 3. 4. Disassembly of LOADING RACK, LOADING ASSY, S/T SLANT POLE ASSY (F

8、ig. 3.6, 3.7) a. Turn out the DECK MECHANISM and remove the LOADING RACK after unscrewing the SCREW . b. Disintegrate the R LOADING AS # and L LOADING AS $ . c. Disintegrate the S SLANT POLE AS %and T SLANT POLE AS by moving those part in arrow dircetion. 3. 5. Disassembly of the A/C HEAD ASSY (Fig.

9、 3.8) a. Remove the CONNECTOR from the AC HEAD ASSY, Watch out that there is no damage in the HEAD connecting 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 AS and SLANT POLE not to be stained

10、 with grease during assembly. Refer to Fig. 3.7 in assembly. FIg. 3.6 Disassembly of the LOADING RACK, LOADING ASSY and the SLANT POLE ASSY FIg. 3.7 Assembly of the L/R LOADING AS and the LOADING RACK CAUTION: After the assembly, adjust the tape transmissionsec- tion by refering to the chapter 5. Af

11、ter the adjustment of the tape transmission section, paint the 3 adjustment screw with locking paint. FIg. 3.8 Disassembly of the AC HEAD ASSY RadioFans.CN 收音机爱 好者资料库 3. 6. Disassembly of the LC BRKT ASSY, PINCH LEVER TOTAL ASSY (Fig. 3.9) a. Separate the LC BRKT Assy after removing the 3 screws !.

12、b. Separate the LC BRKT Assy from the DECK MECHANISM. c. Disintegrate the PINCH LEVER TOTAL Assy #. 3. 7. Disassembly of the CAM GEAR, RELAY LEVER, 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 NTSC colorResolut

13、ion (VCR): Over 220 lines (Standard recording) Antenna: 75 ohm input impedanceResolution (DVD): Over 500 lines (DVD Disc PLAY) Video Signal Level: 1Vp-p (140 IRE standard)Audio (VCR): Over 68dB(Hi-Fi),over 40dB(Mono) Video output (common use of DVD and VCR):Audio (DVD): 100dB VIDEO output terminal,A

14、udio dynamic range: 70dB 1Vp-p (140 IRE standard) Video output (DVD only):S-VIDEO output (75 ohm In load Y: 1Vp-p, C:0.286Vp-p) COMPONENT Progressive output (75 ohm In load Y:1Vp-p, Pb:0.7Vp-p Pr:0.7Vp-p) Note: Specifications are subject to change without notice. CLEANING AND LUBRICATION FIXTURE ITE

15、MDESCRIPTION Path Adj FixtureUse for X-position adjust/Tape path alignment Special DriverUse for X-position adjust/Tape path alignment THE SERVICE FIXTURE Path Adj FixtureSpecial Driver AC Millivolt Meter Sensitivity: 1.0mVAC400VAC Dual-Trace Triggered Oscilloscopewith LoCap (X10) and Direct Probes.

16、 Response: DC20MHz Sensitivity: 5mV/div. Max. Sweep Rate: 0.1sec./div. Frequency Counter7 digits Sensitivity: 25mV-5V Range: 50Hz100MHz DVM Range: 0.1VDC1000VD Accuracy: 0.5% NTSC Video Signal GeneratorMust provide 1V p-p negative sync video across a 75 ohm load and produce standard NTSC 75% saturat

17、ed color bars with a 100% white window. DC Power Supply Range: 0-50V, 2A well filtered. Temperature Controlled Soldering StationGrounded tip (Tip temperature: 500F-600F). Note: 500 F Maximum for leadless components. AC VariacContinuously variable. TEST EQUIPMENT REQUIREMENTS 1. Preparation for repla

18、cement a. Soldering Iron Use a pencil-type soldering iron that uses less than 30 watts. b.Solder Eutectic solder (Tin 63%, Lead 37%) is recommended. c. Soldering time Do not apply heat more than 4 seconds. d.Preheating Leadless capacitor must be preheated before installation. (130C150C, for about tw

19、o minutes). 2. Removing the leadless component (Resistors, Capacitors) Grasp the leadless component body with tweezers and alter- nately apply heat to both electrodes. When the solder on both electrodes is melted, remove leadless component with a twist- ing motion. LEADLESS (CHIP) COMPONENT REMOVAL

20、INSTRUCTION Note: a. Leadless component must not be reused after removal. b.Excessive mechanical stress and rubbing of the compo- nent electrode must be avoided. Note: a. Do not attempt to lift the component off the board until the component is completely disconnected from the board by a twisting ac

21、tion. b.Take care not to break the copper foil on printed board. The following procedures are recommended for the replacement of the leadless components used in this unit. Chip Tweezers Soldering lron PATH FIXTURE CONNECTION/TEST POINT IDENTIFICATION Refer to the adjustment of the tape transporting

22、system. Connect to PT01 !pin-pin of the MAIN CIRCUIT BOARD. CTL pulse test point GND S/W pulse test point ENVE pulse test point ! 3. Installing the Leadless (chip) Component a. Presolder the contact points of the circuit board. b. Press the part downward with tweezers and solder both electrodes as s

23、hown below. 4. Removing of Flat ICs (Recommended procedure) a. For removing solder chips from ICs pins, use a solder remover or a wiry solder absorber. b. Heat the ICs tips evenly by moving the chip IC replacing tool around them, and detach the ICs leads with a tool in the way of using a lever. c. D

24、o not reuse ICs removed once (Discard them) Note: Do not glue the replacement leadless component to the circuit board. Soldering lron Presolder Chip IC replacing tool Soldering lron Solder Tweezers LEADLESS (CHIP) COMPONENT IDENTIFICATION 1. Check the followings before S.M.D Troubleshooting Cracked

25、or Chipped Component Body Cracked or Separated Solder Joints Peeling end Terminations or Fractured Leads 2. S. M. D (Surface Mounted Devices) Identification a. Chip Resistor Identification * Standard Chip Resistor Code b. Chip Capacitor Identification There is no identification of chip capacitor REM

26、ARK Leadless (CHIP) Components are identified on schematic by means of (C) adjacent to symbol numbers. Rejection of Solder from Copper Pads or Component Foreign Matter on Copper Pads Solder Bridges = 12x103(1000) = 12000 = 12K = 47x10 (1) = 47 XXX 123 470 MULTIPLIER (0-9) 2nd SIG. DIGIT (0-9) 1st SI

27、G. DIGIT (1-9) Examples 1.1 Characteristic of T6-DECK MECHANISM 1) T6-MECHA follows the VHS and the NTSC standard. 2) T6-MECHA uses 3 MOTORS (DRUM MOTOR, CAPSTAN MOTOR, L/C MOTOR). 3) T6-MECHA uses L/C Motor to drive FRONT LOADING. 4) T6-MECHA uses 4-BIT MODE signal to recognize each MODE. This 4-BI

28、T MODE signal is generated from the cam switch driven by the L/C MOTOR. 5) T6-MECHA has 7MODES (EJECT/INITIAL/REV/IDLE/PLAY,STOP,SLOW/BRAKE/FF D901,D903,D904,D905,D906, D907,D908,D909,R921. Switching pulse of Q801 drain, Q701 drain is normal? OK Exchange POWER CORD Check D801, TH801, F801,LX801, LX8

29、02. Exchange rectifier diode of 2ndparts ; D901,D903,D904,D905,D906, D907,D908,D909,R921. Check IC801, Q801, IC701, Q701. NO YES YES YES YES YES NO NO NO NO N Caution: When checking the primary circuit, be sure to use an isolation transformer. SYSTEM CIRCUIT No VFD display. Is 5V obtained at IC701 p

30、in#13? Is -24V obtained at IC701 pin#30? Oscillation at IC701 pin #8? Is -24V, +20V obtained at F-, F+? Specific GRID/SEG doesnt function. Check D721. Check POWER circuit at -24V. Check IC701. Check IC 701 pin #3142. Check IC 701 pin #1429. NO YES YES YES YES NO NO NO NO GRID output at PORT of IC701

31、? YES SEG output at PORT of IC701? Check POWER circuit at F-, F+. Exchange IC601. YES A. VFD DISPLAY NO TROUBLESHOOTING GUIDES (Continued) TROUBLESHOOTING GUIDES (Continued) No power compensation. Voltage of power fail (IC601 pin#100) at micom is 0.7V over? More than 3.2V is maintained for 1 minutes

32、 at IC601 pin#37 during Power Cord Open. Check R625. NO YES B. No power compensation. YES Check RESET circuit. NO Exchange IC601. Noise appears on the playback screen. Is noise diminished by tracking adjustment. Noise band is trembled up and down? Re-adjust PATH. Is the height of CTL HEAD normal? No

33、 dust? Is there problem in CTL Input circuit and amplifier. YES NO NO NO Is there CTL pulse at IC601 pin#97? Check IC601. Noise appears on the screen even though changing tape. Re-adjust the height of AC HEAD. Remove the dust. Check C651, C652, R651R653 IC601 pin #91, 92, 98. NO Re-adjust PATH. C-1.

34、 Bad playback quality (1) YES YES YES YES TROUBLESHOOTING GUIDES (Continued) Noise appears on the Full playback screen. Are SW pulse and HA SW normal? Recheck step C-1 (Bad playback quallty (1). Check HEAD AMP connector and HEAD. YES YES NO NO ENVE Wave at PT01 pin #4? Check VIDEO circuit. Are there

35、 SW, HA SW pulse at IC601 pin #16, 18? Check PCB Pattern. Check IC601. C-2. Bad playback quality (2) No broadcasting signal received Is the output at IC601 pin# 71(CLK), 72 (DATA) normal? Is SIF,Video output at TMI(RF101) pin#18,20 normal? Check IC 601. Check IC301. Check IC601. YES YES NO NO NO Is

36、Video Signal input at IC601 pin#50? Is there Video output at IC601 pin#52? Check TMI (RF101) Block. NO Check Video Buffer Q101 D. No broadcasting signal received YES YES NO YES YES YES TROUBLESHOOTING GUIDES (Continued) Cassette tape isnt inserted. Is 5V voltage obtained at Loading parts IC601 pin#8

37、2? Is 13V voltage obtained at Capstan Motor pin#8? Check at Power Circuit 14V. Check (D905, D906). Connect Capstan and Loading Motor. Check connector and Capstan Motor. YES NO NO NO Is 12V voltage obtained at Each parts of Loading Motor? Replace Loading Motor. Check D851 (Main circuit). E. No CASSET

38、TE Loading YES YES F. AUTO STOP in Playback mode VCR stops automatically in playback mode. Check R656,C659 and P603 pin#11 Check P502 connector. Check S603, S604 REEL Sensor. Is D.PG/FG pulse at IC601 pin#90 normal ? Is C. FG pulse at IC601 pin#87 normal ? Is there REEL Pulse at IC601 pin#79, 80? Ch

39、eck and replace IC601. NO YES YES YES NO Check C.FG(R665, C660) and P603 pin#1. NO TROUBLESHOOTING GUIDES (Continued) G. DRUM Motor stops H. CAPSTAN doesnt rotate CAPSTAN doesnt rotate. Is 14V voltage obtained at P603 pin#2? YES NO NO NO YES YES Is Capstan PWM fit to IC 601 pin#77? Is 3.2V voltage o

40、btained at P603 pin#5? Is 23V voltage obtained at P603 pin#9? Check P603 Connector and Capstan Motor. Check 14V. (D905, C906) Check Capstan FG (IC 601 87). Check R665, R664, R663, R666, C665. Check R661, R667, C664. DRUM Motor stops. Is 13V voltage obtained at P603 pin#8? YES NO NO NO YES YES Is DRU

41、M PWM fit to IC 601 pin#76? Is 1.2V voltage obtained at P603 pin#12? Check Capstan Motor and DRUM Motor. Check 14V (P601 #9). Check DRUM PG/FG(IC 601 90). Check R657, R658,C661,C668. NO A. EE screen doesnt appear EE screen doesnt appear. Is video signal input at IC301 pin#28, 30, 32? Is 5V obtained

42、at IC301 pin#23, 44, 45, 52, 68? Is C.S, DATA, CLOCK signal input IC301 pin#53,54,55? Is video signal output at IC601 pin#52? Check IC401, LINE JACK and IF circuit. Check power circiut. Check IC pin#61, 71, 72. NO YES YES YES NO NO NO Is 5V obtained at IC601 pin#53, 98, 99? YES Is signal input at IC

43、401 pin#2? YES NO Check PCB pattern. Is video signal output at IC301 pin#26? YES NO Check IC301 pin#24 QV-sync. Is signal input at IC601 pin#50? YES NO Is 12V obtained at IC401 pin#16? Is C-sync signal input at IC601 pin#58? YES NO Check IC301 pin#25 and PCB pattern. YES Check RF Output.Check Line J

44、ACK output. Check IC 601 YES VIDEO CIRCUIT TROUBLESHOOTING GUIDES (Continued) NO Check power circuit. Check PCB pattern and replace IC401 YES NO Check power circuit. TROUBLESHOOTING GUIDES (Continued) B. Playback picture doesnt appear YES YES Is Y signal output at IC301 pin#35? Is Y signal input at

45、IC301 pin#39? Check and Replace IC301. Playback picture doesnt appear. Is C.S, DATA, CLOCK signal input IC301 pin#53,54,55? NO NO YES Check EE mode and OSD circuit Check IC pin#61, 71, 72. Is 5V obtained at IC301 pin#91? Is 5V obtained at IC301 pin#23,44,45,68? Check power circuit. Clean or Replace

46、HEAD. Check power circuit. YES NO Does X301(3.58MHz) oscillate? Check Pattern. NO NO YES NO YES YES YES Replace X301. Is Video signal output at IC301 pin#26? Replace IC301. NO YES Is SW Pulse input at IC301 pin#57? Is envelope output at IC301 pin#14? YES YES Check IC601 pin#18. NO Replace IC301. NO

47、TROUBLESHOOTING GUIDES (Continued) Is 5V obtained at IC301 pin#68? NO NO YES YES Is VIDEO SW Pulse input at IC301 pin#57? Is REC signal input at IC301 pin#66,73? EP MODE: Pin #73 SP MODE: Pin #66 Check video HEAD and Connector. Is signal input at IC301 pin# 28, 30,32? Check POWER circuit. Check IC60

48、1 pin#18. No recording. Check EE MODE. YES Is FM signal output at IC301 pin#14? Replace IC301. NO NO YES C. No recording TROUBLESHOOTING GUIDES (Continued) NO Is power_on_H signal output at PJ601 pin#11. Change video mode. No Logo display. Do not open tray Is video mode-S-Video mode? Is power suppli

49、ed CN2? (In DVD loader PCB) NO D. No OSD(On Screen Display) appears YES YES Check IC 601 pin#29 and PCB pattern. Is video signal input IC401 pin#1? Is video signal output at P101 pin#1,3,5,7,8,9? NONO Check POWER circuit. YES NO Check DVD loader. Check DVD video buffer (Q103, Q104,Q105,Q106,Q107)and DVD output jack(JK103, JK104) Check PCB pattern. Check IC401 and EE mode. YES YES YES 1. RCA A. No sound in E-E mode TROUBLESHOOTING GUIDES (Continued) AUDIO CIRCUIT No sound in RF E-E mode Check Output JACK. A-1. TV E-E NO Check IC601. Is Audi