Yamaha-MLA-pre-sm 电路图维修手册.pdf

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1、SERVICE MANUAL PA 011727 Copyright (c) Yamaha Corporation. All rights reserved. PDF-K966 I M Printed in Japan 04.3 200406*-73500 I CONTENTS（目次） SPECIFICATION（総合仕様） .3 DIMENSIONS（寸法図）.4 PANEL LAYOUT（） .5 UNIT LAYOUT（） .6 BLOCK DIAGRAM（）.7 WIRING（配線図） .8 DISASSEMBLY PROCEDURE（分解手順） .10 IC BLOCK DIAGRA

2、M（IC 図） .13 CIRCUIT BOARDS（基板図） .14 INSPECTION（検査） .23/25 PARTS LIST OVERALL CIRCUIT DIAGRAM（総回路図） MIC LINE AMPLIFIER ? ? ? ? ? ? ? ? ? ? ? RadioFans.CN 收音机爱好者资料库 MLA8 2 IMPORTANT NOTICE This manual has been provided for the use of authorized Yamaha Retailers and their service personnel. It has bee

3、n assumed that basic service procedures inherent to the industry, and more specifically Yamaha Products, are already known and understood by the users, and have therefore not been restated. WARNING:Failure to follow appropriate service and safety procedures when servicing this product may result in

4、personal injury, destruction of expensive components, and failure of the product to perform as specified. For these reasons, we advise all Yamaha product owners that all service required should be performed by an authorized Yamaha Retailer or the appointed service representative. IMPORTANT:The prese

5、ntation or sale of this manual to any individual or firm does not constitute authorization, certification or recognition of any applicable technical capabilities, or establish a principle-agent relationship of any form. The data provided is believed to be accurate and applicable to the unit(s) indic

6、ated on the cover. The research, engineering, and service departments of Yamaha are continually striving to improve Yamaha products. Modifications are, therefore, inevitable and changes in specification are subject to change without notice or obligation to retrofit. Should any discrepancy appear to

7、exist, please contact the distributors Service Division. WARNING:Static discharges can destroy expensive components. Discharge any static electricity your body may have accumulated by grounding yourself to the ground bus in the unit (heavy gauge black wires connect to this bus). IMPORTANT:Turn the u

8、nit OFF during disassembly and part replacement. Recheck all work before you apply power to the unit. WARNING: CHEMICAL CONTENT NOTICE! The solder used in the production of this product contains LEAD. In addition, other electrical/electronic and/or plastic (where applicable) components may also cont

9、ain traces of chemicals found by the California Health and Welfare Agency (and possibly other entities) to cause cancer and/or birth defects or other reproductive harm. DO NOT PLACE SOLDER, ELECTRICAL/ELECTRONIC OR PLASTIC COMPONENTS IN YOUR MOUTH FOR ANY REASON WHAT- SOEVER! Avoid prolonged, unprot

10、ected contact between solder and your skin! When soldering, do not inhale solder fumes or expose eyes to solder/ flux vapor! If you come in contact with solder or components located inside the enclosure of this product, wash your hands before handling food. I WARNING (安全上注意) Components having specia

11、l characteristics are marked and must be replaced with parts having specification equal to those originally installed. 印部品、安全維持重要部品。交換場合、安全必指定部品使用下。 ? ? ? ? ? ? ? ? ? ? ? RadioFans.CN 收音机爱好者资料库 3 MLA8 I SPECIFICATIONS（総合仕様） Electrical Characteristics 0 dBu is referenced to 0.775 V rms. General Spec

12、ifi cations ConditionsMINTYPMAXUNIT Total Harmonic Distortion (THD+N) 20 Hz - 20 k Hz +14 dBu, 10 k ohms, GAIN Maximum 0.1% 20 Hz - 20 k Hz +14 dBu, 10 k ohms, GAIN Minimum 0.01% Frequency Response 20 Hz - 20 k Hz +4 dBu, 10 k ohms, GAIN Maximum 100.5dB 20 Hz - 20 k Hz +4 dBu, 10 k ohms, GAIN Minimu

13、m 0.500.5dB Hum equivalent to a 20 k Hz fi lter with infi nite dB/octave attenuation. PAD ON , GAIN Minimum ( Sensitivity = +10 dBu ) 82 (92 dB S/N) dBu Maximum Voltage GainCH IN to CH OUT64dB Crosstalk Adjacent Inputs 1 k Hz90dB PAD ON, GAIN Minimum 10 k Hz70dB CH INPUT GAIN controlvariable44dB CH

14、INPUT PAD switch26dB CH High Pass Filter 80 Hz, 12 dB/octave Turn over /roll-off frequency of shelving : 3 dB below maximum variable level. Phantom Power +48 V DC is applied to balanced inputs for powering condenser microphones via 6.8 k ohms current-limiting/isolation resistors. CH PEAK LEDOne red

15、LED per channel. Comes on when post GAIN signal level reaches +17 dBu. CH SIGNAL LEDOne green LED per channel. Comes on when post GAIN signal level reaches -10 dBu. Included AccessoriesPower Supply Cord, Euroblock Connectors ( 3P x 8 ), Rubber Feet ( x 4 ), Owners Manual Power Consumption25 W Dimens

16、ions (W x H x D)480 mm x 44 mm x 375.5 mm Weight4.7 kg ? ? ? ? ? ? ? ? ? ? ? RadioFans.CN 收音机爱好者资料库 MLA8 4 Iuput Characteristics *1: 0 dBu is referenced to 0.775 Vrms. Output Characteristics *1: 0 dBu is referenced to 0.775 Vrms. D-sub 25pin Assignment Table PADGain Actual Load Impedance For Use Wi

17、th Nominal Input Level *1 Connector In Amplifi er unit NominalMax. before Clip 0 60 3 k ohms 50 600 ohms Mics 600 ohms Lines 60 dBu (0.775 mV) 40 dBu (7.75 mV) XLR-3-31type (balanced) 26 34 dBu (15.5 mV) 14 dBu (155 mV) 0 16 16 dBu (123 mV) +4 dBu (1.23 V) 26 +10 dBu (2.45 V) +30 dBu (24.5 V) Actual

18、 Source Impedance For Use With Nominal Output Level *1 Connector In Amplifi er unit NominalMax. before Clip 150 ohms10 k ohms Lines +4 dBu (1.23 V) +24 dBu (12.3 V) Euroblock connectors (balanced) D-SUB 25P female connector (balanced) Signal Output Ch OpenGND 12345678 Pin Hot 2410217184151 2, 5, 8,

19、11, 16, 19, 22, 25 1223920617314 13 Cold2514 131 439 430 375.5 353.5 17 348 43 51220 65350 480 44 45 22 423 -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 1 MIC LINE AMPLIFIER POWER ON /OFF 26dB * Unit （単位）：mm -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 2 26dB -16 +10-34 -60 GAIN SIGNAL PEAK OFFON

20、+48V 80 3 26dB -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 4 26dB -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 5 26dB -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 6 26dB -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 7 26dB -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 8 26dB * When the included

21、rubber feet are attached.（付属脚取付時） I DIMENSIONS（寸法図） ? ? ? ? ? ? ? ? ? ? ? 5 MLA8 I PANEL LAYOUT（） q w e r t y u POWER/ 80 26dB +48V PEAK SIGNAL GAIN q w e r t y u POWER switch and indicator 80 buttons 26dB buttons +48V switches PEAK indicators SIGNAL indicators GAIN controls i o !0 AC IN connector I

22、NPUT 1-8 connectors OUTPUT connectors i o !0 AC IN 端子 INPUT 18 端子 OUTPUT 端子 -16 +10-34 -60 GAIN -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V SIGNAL PEAK OFFON +48V 8080 -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48

23、V 80 -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 12345678 MIC LINE AMPLIFIER POWER ON /OFF 26dB26dB26dB26dB26dB26dB26dB26dB -16 +10-34 -60 GAIN SIGNAL PEAK OFFON +48V 80 26dB q w e r t y u 12345678 INPUT 12

24、345678 GG ANALOG OUTPUT +4dBu OUTPUT +4dBu AC IN !0 oi + G Front Panel（） Rear Panel（） Euroblock Connectors（端子） ? ? ? ? ? ? ? ? ? ? ? MLA8 6 I UNIT LAYOUT（） Top View（上側） Front panel () Power Transformer (電源) AC INLET (AC) AC INLET (AC) Power Transformer (電源) Front panel () HAJK 1/4 HAJK 3/4HAJK 2/4 I

25、N PS 2/2 PS 1/2 HAJK 4/4 Bottom Shassis Assembly (Assy) Bottom Shassis Assembly (Assy) ? ? ? ? ? ? ? ? ? ? ? 7 MLA8 I BLOCK DIAGRAM（） IN IN 28CA1-8830823 IC101 IC101 SW102 IC102 SP101 CN114 LD101 PEAK SIGNAL LD102 VR101 SW101 SW501 JK101 CN102 CN101 3P 9P 9P 3P 7 1 5 1 2 5P 5P CN107 CN101 CN102 CN10

26、3 CN108 CN112 CN110 CN113 CN111 HAJK 3/4 CH1-4 CH5-8 CH2-4 CH5-8 CH2 CH1 CH2 CH8 CH7 AC INLET CN104 SW101 POWER F101 FUSE CN105 3P 4P TRANSFORMER CN101 PS 2/2 T100 PS 1/2 CN102CN103 IC101 +15V -15V IC102 +12V IC102 +15V -15V +15V IC104 +48V -15V HAJK 2/4 HAJK 1/4 CN109 CN105 3P CN807 CN101 CN801 CN8

27、02 CN103 IN CN102 PEAK SIGNAL 7 5 1 3P IC101 CN103 +15V 9P-B -15V +12V +15V +12V +15V +12V +15V +12V +48V +15V +12V CN703 CN708 IN HAJK 4/4 CN106 CN104 +12V LD101 POWER SP701 JK801 3P 3P 3P 9P 9P 3P +15V -15V CH7 CH8 12P 12P-B 12P 12P-B 6P-B 6P 9P 2P-B 2P 5P 5P 2 8 +15V -15V 4 +15V 8 -15V 4 8 +15V -

28、15V 4 31 67 6 7 8 +15V IC101 -15V 4 IC101 SW102 31 LD101 LD102 8 +15V 4 -15V 8 +15V 4 -15V 2 3 1 2 3 +12V +12V 5P ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? MLA8 8 I WIRING（配線図） Power Transformer PS 1/2 PS 2/2 HAJK 2/4 HAJK 3/4 HAJK 1/4 HAJK 4/4 IN IN Power Transformer 8 1

29、0 11 9 5 4 3 7 6 20 2 1 8 9 10 11 12 12 13 14 15 16 17 18 19 2 IN 3 IN 4 IN 5 IN 6 IN 7 IN 8 121 AC INLET 1 13 14 15 16 17 18 19 29 22 30 23 31 24 32 25 33 26 34 27 35 28 36 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 9 MLA8 q w e r t y u i o !0 !1 !2 !3 !4 !5 !6 !7 !8 !9 0

30、 1 2 3 4 5 6 7 8 9 #0 #1 #2 #3 #4 #5 #6 (AC INLET) PS 2/2-CN105 (Power Transformer) PS 1/2-CN103 PS 1/2-CN102 HAJK 2/4-CN110 HAJK 2/4-CN111 HAJK 2/4-CN108 HAJK 2/4-CN308 HAJK 2/4-CN508 HAJK 2/4-CN708 HAJK 2/4-CN107 HAJK 2/4-CN207 HAJK 2/4-CN307 HAJK 2/4-CN407 HAJK 2/4-CN507 HAJK 2/4-CN607 HAJK 2/4-C

31、N707 HAJK 2/4-CN807 HAJK 1/4-CN104 HAJK 1/4-CN101 HAJK 1/4-CN201 HAJK 1/4-CN301 HAJK 1/4-CN401 HAJK 1/4-CN501 HAJK 1/4-CN601 HAJK 1/4-CN701 HAJK 1/4-CN801 HAJK 1/4-CN102 HAJK 1/4-CN202 HAJK 1/4-CN302 HAJK 1/4-CN402 HAJK 1/4-CN502 HAJK 1/4-CN602 HAJK 1/4-CN702 HAJK 1/4-CN802 PS 2/2-CN104 (Power Trans

32、former) PS 1/2-CN101 HAJK 2/4-CN109 HAJK 1/4-CN105 HAJK 3/4-CN112 HAJK 3/4-CN113 HAJK 1/4-CN103 HAJK 1/4-CN303 HAJK 1/4-CN503 HAJK 1/4-CN703 IN-CN101 (1) IN-CN101 (2) IN-CN101 (3) IN-CN101 (4) IN-CN101 (5) IN-CN101 (6) IN-CN101 (7) IN-CN101 (8) HAJK 4/4-CN106 IN-CN102 (1) IN-CN102 (2) IN-CN102 (3) I

33、N-CN102 (4) IN-CN102 (5) IN-CN102 (6) IN-CN102 (7) IN-CN102 (8) IN-CN103 (1) IN-CN103 (2) IN-CN103 (3) IN-CN103 (4) IN-CN103 (5) IN-CN103 (6) IN-CN103 (7) IN-CN103 (8) DESTINATION（配線先） C (Pin3) C (Pin6) C (Pin9) B (Pin12) B (Pin12) C (Pin3) C (Pin3) C (Pin3) C (Pin3) C (Pin3) C (Pin3) C (Pin3) C (Pi

34、n3) C (Pin3) C (Pin3) C (Pin3) C (Pin3) C (Pin2) C (Pin5) C (Pin5) C (Pin5) C (Pin5) C (Pin5) C (Pin5) C (Pin5) C (Pin5) C (Pin9) C (Pin9) C (Pin9) C (Pin9) C (Pin9) C (Pin9) C (Pin9) C (Pin9) C (Pin4) C (Pin5) B (Pin6) B (Pin9) C (Pin12) C (Pin12) C (Pin3) C (Pin3) C (Pin3) C (Pin3) C (Pin3) C (Pin

35、3) C (Pin3) C (Pin3) C (Pin3) C (Pin3) C (Pin3) C (Pin3) B (Pin2) C (Pin5) C (Pin5) C (Pin5) C (Pin5) C (Pin5) C (Pin5) C (Pin5) C (Pin5) C (Pin9) C (Pin9) C (Pin9) C (Pin9) C (Pin9) C (Pin9) C (Pin9) C (Pin9) No. - - - * C: Connector B: Board-in (Soldering) ? ? ? ? ? ? ? ? ? ? ? MLA8 10 I DISASSEMB

36、LY PROCEDURE（分解手順） 1. （所要時間: 約2分） 1-1. 3205本3254本外、340 6本外、外。(Fig. 1) 1.Top Cover (time required: about 2 minutes) 1-1 Remove the five (5) screws marked 320, the four (4) screws marked 325, the angle bracket and the six (6) screws marked 340. The top cover can then be removed. (Fig. 1) 320: Bind He

37、ad Tapping Screw-S 3.0 x6 MFZN2BL (EP630210) +S 325: Flat Head Tapping Screw-S 3.0 x6 MFZN2BL (WD010800) +S平頭 340: Bind Head Tapping Screw-S 4.0 x8 MFZN2BL (VI693100) +S (Fig. 1) Top Cover () Angle Bracket, Rack () 340 340 320 320 320 325 2. （所要時間: 約3分） 2-1. 外。(1項参照) 2-2. 2902本3001本外、外。(Photo. 1, 4

38、) 3. 電源（所要時間: 約3分） 3-1. 外。(1項参照) 3-2. 454本外、外、電源抜出。 (Photo. 1, 2) 4. AC（所要時間: 約3分） 4-1. 外。(1項参照) 4-2. 602本3901本外、AC 外。(Photo. 3) 2.Front Panel (time required: about 3 minutes) 2-1 Remove the top cover. (See Procedure 1.) 2-2 Remove the two (2) screws marked 290 and the screw marked 300. The front p

39、anel can then be removed. (Photo. 1, 4) 3.Power Transformer (time required: about 3 minutes) 3-1 Remove the top cover. (See Procedure 1.) 3-2Remove the four (4) screws marked 45 and the shield case. The power transformer can then be removed. (Photo. 1, 2) 4.AC Inlet (time required: about 3 minutes)

40、4-1 Remove the top cover. (See Procedure 1.) 4-2Remove the two (2) screws marked 60 and the screw marked 390. The AC inlet can then be removed. (Photo. 3) 45: Bind Head Tapping Screw-S 3.0 x6 MFZN2BL (EP630210) +S 60: Bind Head Tapping Screw-S 3.0 x8 MFZN2BL (EP600530) +S 290: Bind Head Tapping Scre

41、w-S 3.0 x6 MFZN2BL (EP630210) +S 390: Bind Head Tapping Screw-S 4.0 x8 MFZN2BL (VI693100) +S (Photo. 1)(Photo. 3) Power Transformer (電源) 45 Shield case ()Shield case () Power Transformer (電源) (Photo. 2) AC INLET (AC)AC INLET (AC) 45 290290 390390 6060 ? ? ? ? ? ? ? ? ? ? ? 11 MLA8 5. PS 1/2（所要時間: 約3

42、分） 5-1. 外。(1項参照) 5-2. 1406本外、PS 1/2外。(Photo. 4) 5.PS 1/2 Circuit Board (time required: about 3 minutes) 5-1 Remove the top cover. (See Procedure 1.) 5-2 Remove the six (6) screws marked 140. The PS 1/2 circuit board can then be removed. (Photo. 4) Front panel () Power Transformer (電源) 110, 140, 200

43、: Bind Head Tapping Screw-B 3.0 x6 MFZN2BL (EP630210) +S 300: Flat Head Tapping Screw-S 3.0 x6 MFZN2BL (WD010800) S平頭 (Photo. 4) 140 110 200200 300 AC INLET (AC) 200 AC INLET (AC) Power Transformer (電源) Front panel () HAJK 1/4 PS 1/2 HAJK 3/4HAJK 2/4 110 110110 IN PS 2/2 200 300 6. HAJK 1/4（所要時間: 約4分） 6-1. 外。(1項参照) 6-2. 外。(2項参照) 6-3. 2108個3508個外、 A六角8個外、2004本外、HAJK 1/4外。 (Photo. 4, 5) 7. IN（所要時間: 約4分） 7-1. 外。(1項参照) 7-2.