Kenwood-DMCG7R-md-sm 电路图 维修手册.pdf

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1、S: SILVER, B: BLUE Decoration plate (B07-2372-08) Knob (PLAY/PAUSE) (K27-2229-08) Knob (STOP) (K27-2231-08) Knob (REC) (K27-2227-08) Front cabinet (A02-1357-08): S (A02-1358-08): B Knob (EJECT) (K27-2232-08) Cover (F07-1624-08) Knob (EDIT MODE) (K27-2230-08) Top cover (F07-0798-08): S (F07-0799-08):

2、 B POTABLE MD RECORDER DMC-G7R SERVICE MANUAL 1997-7/B51-5335-00 (K/K) 2740 In compliance with Federal Regulations, following are reproduc- tions of labels on, or inside the product relating to laser product safety. KENWOOD-Corp. certifies this equipment conforms to DHHS Regulations No. 21 CFR 1040.

3、 10, Chapter 1, Subchapter J. DANGER : Laser radiation when open and interlock defeated. AVOID DIRECT EXPOSURE TO BEAM. SPECIFICATIONS System.MiniDisc digital audio system Read method.Noncontact optical reading system (semiconductor laser) Rotating speed.About 400 - 900 rpm Sampling frequency.44.1 k

4、Hz (32 kHz and 48 kHz are converted to 44.1 kHz and recorded) Audio compression.ATRAC (Adaptive Transform Acoustic Coding) Number of channels.Stereo : 2 Channels Monaural Extended mode : 1 channel Recording method.Magnetic modulation overwrite system Error correction method.AC / RC method Frequency

5、response.20 Hz to 20,000 Hz (3 dB) Wow microphone x 1 (plug-in power type) Output jack .Headphone/remote control combined jack Input sensitivity : MIC H.0.25 mV/10 k MIC L.2.5 mV/10 k LINE .100 mV/20 k Output level :phones.10 mW + 10 mW (Maximum output level/at 16) LINE .350 mV (at -12dB, standard o

6、utput/50 k) Power source.DC 5 V: AC adaptor (AC 120 V, 50/60 HZ) DC 3.6 V : Lithium ion battery x 1 DC 5 V: Car battery adaptor (sold separately, DC-C50) DC 4.5 V : Dry batteries case (sold separately, BC-F5) Battery life. (fully charged batteries) Dimensions (W) x (H) x (D) .109.2 mm x 29.8 mm x 81

7、.3 mm (4-5/16 x 1-3/16 x 3-3/16) Weight (Net).Approx. 270 g (0.59 lb) Including the accessory rechargeable battery Approx. 222g (0.49 lb) not including the accessory rechargeable battery (Continuous recording time : based on analog input and recording monitor volume level of 0 (Continuous playback t

8、ime : based on volume level of VOL 20) Time of use may vary depending on battery maker, batter type, use environment, and temperature. 1. KENWOOD follows a policy of continuous advancements in development, For reason specifications may be changed without notice. 2. The full performance may not be ex

9、hibited in an extremely cold location (under a water-freezing temperature). Type of battery ContinuousContinuous playback timerecording time Rechargeable battery onlyApprox. 9.5 hoursApprox. 7 hours Alkaline batteriesApprox. 24 hours Approx. 17 hours Rechargeable battery +Approx. 35 hours Approx. 25

10、 hours Alkaline batteries NotesNotes DMC-G7R(k) COVER( 98.4.24 2:19 PM yW 2 RadioFans.CN 收音机爱 好者资料库 DMC-G7R 2 CONTENTS / ACCESSORIES Accessories AC adaptor(1) (W08-0668-08) : K (W08-0669-08) : M (W08-0670-08) : E (W08-0671-08) : T Rechargeable battery (NB-L5) (1) (W03-5679-08) Remote control (1) (A7

11、0-1129-05) : M Remote control unit (1) (A70-1177-05) : KET Carrying case (1) (W01-0918-08) Stereo headphone(1) (W01-0920-15) : MET Stereo headphone(1) (W01-0941-15) : K Patch cord (1) (E30-2836-08) Contents SPECIFICATIONS.Front cover CONTENTS / ACCESSORIES .2 DISASSEMBLY FOR REPAIR.3 TROUBLE SHOOTIN

12、G.5 PC BOARD .19 SCHEMATIC DIAGRAM .23 EXPLODED VIEW .27 PARTS LIST.29 DMC-G7R(k) COVER( 98.4.24 2:19 PM yW 3 RadioFans.CN 收音机爱 好者资料库 Caution on Disassembly Follow the below-mentioned notes when disassembling the unit and reassembling it, to keep it safe and ensure excellent performance: 1. Take the

13、 battery and minidisc out of the unit. 2. When disassembling the machine, be sure to withdraw the power plug from the socket in advance. 3. When disassemble the parts, remove the nylon band or wire holder as necessary. To assemble after repair, be sure to arrange the wires as they were. If a screw o

14、f different length is fitted to the MD mecha- nism (the screw of the part to be fitted to the MD mechanism chassis), it may contact the optical pickup, resulting in malfunction. 4. When repairing, pay due attention to electrostatic charges of IC. 1Bottom Cover1. Screw . (A1) x57-1 2Disc Cover1. Scre

15、w . (B1) x47-1 (Note)2. Flexible PWB . (B2) x1 3Main PWB1. Screw . (C1) x37-2 2. Flexible PWB . (C2) x4 3. Soldering . (C3) x2 4Front Cabinet1. Screw . (D1) x17-2 2. Remove the front cabinet in the arrow direction. REMOVALPROCEDURESTEPFIGURE Bottom Cover (B1) x2 2x2mm (B1) x2 2x2mm (A1) x2 2x2mm (A1

16、) x2 2x2mm (A1) x1 2x2mm (B2) x1 Disc Cover Figu re 7-1 Figure 7-2 Eject knob lever Eject leverLid opening and closing spring Lid opening and closing spring Lid opening and closing lever Engage the spring at the upper side. Lid opening and closing lever Figure Figure 7-3 Figure 7-4 Note: When removi

17、ng the upper lid, at first turn the operation knob side in the arrow direction to remove. Installing the front cabinet (See Fig. 7-3.) 1. Make sure that the lid opening and closing spring has been engaged at the upper side as shown in Figure . 2. Fit the MD lid right pin into the lid opening and clo

18、sing lever to install it. Note: Take care since the antivibration rubber may come off. If the main PWB has been installed previously, fit the knob to the HOLD switch shown in Figure . If the mechanism has been installed, the antivibration rubber may come off from the center cabinet fitting part when

19、 the front part of center cabinet is widened. (C1) x3 2x2.5mm (D1) x1 2x2.5mm (C3) x1 (C2) x2 (C3) x1 Main PWB Front Cabinet (C2) x2 Front Cabinet Lid opening and closing lever Center Cabinet Antivibration rubber HOLD knob MD lid MD lid right pin SW DMC-G7R 3 DISASSEMBLY FOR REPAIR DMC-G7R(k) COVER(

20、 98.4.24 2:19 PM yW 6 RadioFans.CN 收音机爱 好者资料库 DMC-G7R 4 DISASSEMBLY FOR REPAIR Remove the mechanism according to the disassembling meth- ods 1 to 4. (See Page 7.) How to remove the disc motor (See Fig. 8-1.) 1. Remove the solder joint (A1) x 1 of flex PWB. 2. Remove the screws (A2) x 3 pcs. and remo

21、ve the disc motor. Take care so that the turnrable is not damaged. Figure 8-4 (A2) x 3 1.4 x 4.5mm Flexible PWB solder joint (A1) x1 Disc Motor Motor Spacer Mechanism PWB Mechanism Figure 8-1 (B2) x2 1.4x2.2mm (B1) x2 Remove the solder joint. Slide Motor Figure 8-2 Figure 8-3 Shaft (C2) x 1 (C1) x 2

22、 1.4 x 3mm (C1) x 1 1.4 x 2.5mm (C1) x 1 2 x4.5mm Pickup Unit Magnetic field arm block Magnetic head Head intervening flexible PWB (D1) x1 1.4x2mm Unsolder (D2) x2 How to remove the slide motor (See Fig. 8-2.) 1. Remove the solder joint (B1) x 1 of slide motor lead wire. 2. Remove the screw (B2) x 1

23、, and remove the slide motor. Note: Take care so that the motor gear is not damaged. (If the gear is damaged, noise is raised in search mode.) How to reinstall the optical pickup unit (See Fig. 8-3.) 1. Remove the screws (C1) x 5 pcs. 2. Remove the magnetic fielt arm block from the pickup, and move

24、the magnetic field arm block outwards. Note: Take due care so that the magnetic head is not damaged. 3. Withdraw a little the slide motor side shaft (C2) x 1 pcs., and slowly raise the optical pickup. How to remove the magnetic head (See Fig. 8-4.) 1. Remove the screw (D1) x 1 pc. 2. Remove the unso

25、lder (D2) x 2 pcs. which connects the magnetic head and the head hookup flex. Note: Mount carefully so as not to damage the magnetic head. DMC-G7R(k) COVER( 98.4.24 2:19 PM yW 7 DMC-G7R 5 TROUBLE SHOOTING Abnormal display No Yes Is waveform output from IC 401 pins 13 to 15? Check for pattern breakag

26、e of flexible PWB, check for defects of display microcomputer (replace the display unit). Is waveform output from CNS 402 pins 1 to 3? Are the pin7 (VCC) and pin 6 (GND) normal? Playback state cannot be set Is playback state unsettable for high reflection disc and low reflection disc? Yes Check betw

27、een IC401 and CNS402. No Check the periphery of IC401. Proceed to Test mode check. Yes Only the low reflection disc cannot be played back. Only the high reflection disc cannot be played back. Yes Is the pin 46 of IC401 in L state when the high reflection disc is inserted? Is the pin 51 of IC401 and

28、pin 23 of IC101 in L state? Check SW902, mechanism flexible PWB and CN601. No Proceed to Test mode check. Yes No Yes Is the pin 46 of IC401 in L state when the high reflection disc is inserted? Is the pin 51 of IC401 and pin 23 of IC101 in L state? No Proceed to Test mode check. Yes Check SW902, mec

29、hanism flexible PWB and CN601. It is advisable to use the TEST mode (refer to Error Data Display Mode, P15) indicating the causes of troubles before starting repair. Causes of operation errors (up to 10 errors) are recorded as error codes. This information is useful for repair. When does not functio

30、n 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. Remove the cabinet and

31、 follow the troubleshooting instructions. Track skipping and/or no TOC(Table Of Contents) may be caused by build up of dust other foreign matter on the laser pickup lens. Before attempting any adjustment make certain that the lens is clean. If not, clean it as mentioned below. Turn the power off. Ge

32、ntly clean the lens with a lens cleaning tissue and a small amount of isopropyl alcohol. Do not touch the lens with the bare hand. Is the power supply turned on when the remote control button or main unit button is pressed? No Perform the check stated in item Power is not turned on when the PLAY but

33、ton is pressed. Perform the check stated in item Abnormal display. No Yes Does the display operate normally? Is playback state set? Yes Perform the check stated in item Playback state connot be set. No Is audio output normal? Yes Perform the check stated in item Audio playback circuit. No Is recordi

34、ng/playback operation normal? Yes Perform the check stated in item Recording/playback operation. No Power is not turned on when the / button is pressed. No No Yes Check the periphery of remote controller and main unit headphone terminal (J703) and IC401. No Is the pin 26 of IC401 in H state? Is oper

35、ation normal when the main body button is pressed? Check the position of Hold switch. Is power turned on when the remote control button is pressed? No Are IC401 pin 50 set to L?Check the DISC IN (SW904) switch of mechanism PWB. Yes Yes Is clock supplied to the pins 83 and 86 of IC401? No Check that

36、voltage is applied to the periphery of IC403. Yes Is 2.5V applied to TP201? No Check whether there is solder touch of part connected to the +2.5V line. DMC-G7R(k) COVER( 98.4.24 2:19 PM yW 10 DMC-G7R 6 TROUBLE SHOOTING Continued from the preceding page In case of high reflection disc, proceed to the

37、 item normal playback.In case of low reflection disc, check whether adjustment is within allowable range in the TOTAL level adjustment step. Check whether values of pins 10, 11, 14, and 15 of IC201 and pins 30 and 32 of IC101 (TP143) change when the / button is pressed. No Doesnt the disc motor run

38、at high speed in the same step? Check ADIP waveform of pin 4 of IC201. No Yes Is tracking gain adjustment within allowable range in the same step? Check whether values of pins 16 to 19 of IC201 and TP144 (TEOUT) change when the / button is pressed. No Yes Is adjustment within allowable range in trac

39、king error balance adjustment step? Check whether value of pin 20 of IC201 and TP144(TEOUT) changes or DC shift occurs when the / button is pressed. No Yes Is tracking servo applied in focus gain fine adjustment step? Check waveforms of pins 54 and 55 of IC201, pins 18, 19, 21, and 23 of IC601, pins

40、 4 and 6 of CNS101. No Yes Is slide servo applied in continuous playback step? Replace IC201. No Yes Yes Check item Normal Playback. Test mode check Insert a high reflection (low reflection) disc, and once perform automatic adjustment in AUTO mode, and then check in MANUAL mode. Simultaneously obser

41、ve waveforms of EFM(TP145), FEOUT(TP143), and TEOUT(TP144). Does the optical pickup move to outer/inner periphery when the / button is pressed? Check the pins 56 and 57 of IC201, the pins 25, 27, 29 and 30 of IC601, the pins 10 and 11 of CNS601, and the slide motor terminal. No Is tracking error off

42、set measurement within allowable range? Yes Check Vref values of pins 3 and 4 of IC101 and pin 22 of IC201. No Is focus error offset measurement within allowable range? Yes Check Vref values of pins 3 and 4 of IC101 and pin 22 of IC201. No Yes Is laser power normal when laser lights? Check the pins

43、21 and 22 of IC101, the pins 6 and 52 of IC401, the periphery of Q101, Q102, and Q103, CNS101, and pickup flexible PWB insertion. No Yes Does focus access occur in focus gain rough adjustment step? Check the pins 52 and 53 of IC201, the pins 10, 12, 14, and 15 of IC601,and the pins 5 and 7 of CNS101

44、. No Yes Is adjustment out of allowable range? Check whether values of pins 10, 11, 14, and 15 of IC201, pins 30 and 32 of (IC101) (TP143) change when the / button is pressed. No Does the disc motor rotate in the same step? Check as stated in item The disc motor does not rotate. No Is focus servo ap

45、plied in tracking gain adjustment step? Check timing of pins 91 and 92 of IC401 and TP144(TEOUT). No Yes Yes Doesnt the disc motor rotate at high speed in the same step? No Check EFM waveform of pin 23 of IC201 in case of high reflection. Check ADIP waveform of pin 4 of IC201 in case of low reflection. Yes Is tracking gain adjustment within allowable range in the same step? Check whether values of pins 16 to 19 of IC201 and TP144(TEOUT) change when the / button is pressed. No Yes Is adjustment within allowable range in tracking error balance adjustment step? Check whether value of pin 20