Yamaha-MG8-mix-sm 电路图维修手册.pdf

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1、SERVICE MANUAL PA HAMAMATSU, JAPAN Copyright (c) Yamaha Corporation. All rights reserved. PDF-K1941 M I 04.12 011744 20050110-23000 CONTENTS（目次） SPECIFICATIONS（総合仕様） .3/5 DIMENSIONS（寸法図） .7 CIRCUIT BOARD LAYOUT（）. 7 PANEL LAYOUT（） .8 DISASSEMBLY PROCEDURE（分解手順） .11 LSI PIN DESCRIPTION（ LSI 端子機能表） .1

2、5 IC BLOCK DIAGRAM（IC 図） .16 CIRCUIT BOARDS（基板図）. 17 INSPECTIONS（検査） .22/27 BLOCK DIAGRAM equivalent to a 20 kHz filter(EFFECT SEND) with infinite dB/octave attenuation.ST Master Control and one CH LEVEL Control -64 dBu at nominal level. (CH1, 2) (ST OUT)(68 dB S/N) CH MIC INPUT to CH INSERT OUT 60

3、dB CH MIC INPUT to ST OUT 76 dB Maximum Voltage GainCH MIC INPUT to REC OUT64.2 dB CH MIC INPUT to EFFECT SEND 70 dB ST CH MIC INPUT to ST OUT 76 dB PAN/BAL : panned hard left or hard right.ST CH LINE INPUT to ST OUT 50 dB ST CH LINE INPUT to EFFECT SEND 41 dB ST CH INPUT to ST OUT 26 dB RETURN to S

4、T OUT 12 dB 2TR INPUT to ST OUT23.8 dB Crosstalk (1 kHz)Adjacent inputs -70 dB input to output -70 dB Monaural/Stereo Input GAIN Controlvariable range 44 dB Where 0 dBu = 0.775 V General Specifications Monaural/Stereo CH High Pass Filter80 Hz 12 dB/octave Monaural/Stereo CH Equalization +/-15 dB (Ma

5、x. Variation) Turn over /roll-off frequency of shelving, 3 dBHIGH: 10 kHz (shelving) below maximum variable levelMID: 2.5 kHz (peaking) LOW: 100 Hz (shelving) Internal Digital Effect16 programs, Parameter control FOOT switch (ON/OFF) Phantom PowerSupplied when Phantom +48 V switch is ON. (XLR-type i

6、nput jacks) Monaural/Stereo Input PEAK IndicatorOn each channel: red indicator lights if post-EQ signal (on ST channels, if either post-EQ signal or post-mic-amp signal) comes within 3 dB of the clipping level. Two 12-points LED level meters ST (L, R) Level MetersPeak point: red indicator +5, +3, +1

7、, 0: yellow indicators -1, -3, -5, -7, -10, -15, -20: green indicators Included AccessoriesPower adaptor (PA-10) OptionsMicrophone-stand adaptor (BMS-10A), Footswitch (FC5) Power Consumption25 W Dimensions (W x H x D)251 mm x 65 mm x 290.5 mm Weight1.8 kg Where 0 dBu = 0.775 V RadioFans.CN 收音机爱好者资料

8、库 4 MG8 / 2FX Input Specifications Input ConnectorGain Input AppropriateSensitivity* NominalMax. Before Connector Impedance Impedance Level Clipping Specifications -60-72 dBu-60 dBu-40 dBu MIC INPUT 3k 50-600 mic(0.195 mV)(0.775 mV)(7.75 mV)XLR-3-31 type (CH 1, 2)-16-28 dBu-16 dBu+4 dBu(balanced) (3

9、0.9 mV)(123 mV)(1.23 V) -34-46 dBu-34 dBu-14 dBuPhone jack (TRS) LINE INPUT 10k 600 line(3.88 mV)(15.5 mV)(155 mV)(balanced T: hot; (CH 1, 2)+10-2 dBu+10 dBu+30 dBuR: cold; (0.616 V)(2.45 V)(24.5 V)S: ground) ST CH MIC INPUT-60-72 dBu-60 dBu-40 dBu (CH3(L)/CH4(R), 3k 50-600 mic(0.195 mV)(0.775 mV)(7

10、.75 mV)XLR-3-31 type CH5(L)/CH6(R)-16-28 dBu-16 dBu-10 dBu(balanced) (30.9 mV)(123 mV)(245 mV) ST CH LINE INPUT-34-46 dBu-34 dBu-14 dBu (CH3(L)/CH4(R), 10k 600 line(3.88 mV)(15.5 mV)(155 mV)Phone jack CH5(L)/CH6(R)+10-2 dBu+10 dBu+30 dBu(unbalanced) (0.616 V)(2.45 V)(24.5 V) ST CH INPUT-22 dBu-10 dB

11、u+10 dBuPhone jack (CH7(L)/CH8(R) 10k 600 line(61.6 mV)(245 mV)(2.45 V)(unbalanced); RCA pin jack Phone jack (TRS) CH INSERT IN 10k 600 line-20 dBu0 dBu+20 dBu(unbalanced (CH 1, 2)(77.5 mV)(0.775 V)(7.75 V)T: out; R: in; S: ground) RETURN (L, R) 10k 600 line-12 dBu+4 dBu+24 dBuPhone jack (195 mV)(1.

12、23 V)(12.3 V)(unbalanced) 2TR IN (L, R) 10k 600 line-26 dBV-10 dBV+10 dBVRCA pin jack (50.1 mV)(316 mV)(3.16 V) Where 0 dBu = 0.775 V and 0 dBV= 1 V * Input sensitivity: the lowest level that will produce the nominal output level when the unit is set to maximum gain. Output Specifications Output Con

13、nectorsOutput ImpedanceAppropriate Nominal Level Max. Before Connector Specifications Impedance Clipping Phone jack (TRS) ST OUT (L, R) 150 10k line+4 dBu (1.23 V)+20 dBu (7.75 V)(impedance balanced T: hot; R: cold; S: ground) Phone jack (TRS) EFFECT SEND 150 10k line +4 dBu (1.23 V)+20 dBu (7.75 V)

14、(impedance balanced T: hot; R: cold; S: ground) CH INSERT OUTPhone jack (TRS) (CH 1, 2) 150 10k line0 dBu (0.775 V)+20 dBu (7.75 V)(unbalanced T: out; R: in; S: ground) REC OUT (L, R) 600 10k line-10 dBV (316 mV)+10 dBV (3.16 V)RCA pin jack Phone jack (TRS) C-R OUT (L, R) 150 10k line+4 dBu (1.23 V)

15、+20 dBu (7.75 V)(impedance balanced T: hot; R: cold; S: ground) PHONES 100 40 phone3 mW75 mWStereo phone jack Where 0 dBu = 0.775 V and 0 dBV= 1 V 5 MG8 / 2FX 総合仕様電気的特性電気的特性電気的特性電気的特性電気的特性条件最小標準最大単位 (THD+N) 20 Hz 20 kHz +14 dBu 10 k ohms 全高調波歪率(MIC ST OUT) (CH1、2) ( 信号入力LEVEL 、 0.1 ST Master =

16、 ) 周波数特性(MIC ST OUT) 20 Hz 20 kHz +4 dBu 10 k ohms -3 0 1 dB (GAIN 最小) 入力換算(CH1、2) -128 dBu & (20 Hz 20 kHz) 残留(ST OUT) -100 dBu ST 、 -87 Rs=150ohms、Gain= 最大、全LEVEL最小(ST OUT) （91 dB S/N) dBu 感度= -60 dBu、12.7 kHz、全EFFECT 最小、 -85 -6 dB/octave測定全LEVEL 最小(EFFECT SEND) （89 dB S/N) dBu (20 kHz、- dB/oct

17、ave 相当) ST &1 LEVEL -64 (CH1、2)(ST OUT) （68 dB S/N) dBu CH MIC INPUT CH INSERT OUT 60 dB CH MIC INPUT ST OUT 76 dB CH MIC INPUT REC OUT 64.2 dB 最大電圧 CH MIC INPUT EFFECT SEND 70 dB ST CH MIC INPUT ST OUT 76 dB PAN/BAL：左右回切 ST CH LINE INPUT ST OUT 50 dB ST CH LINE INPUT EFFECT SEND 41 dB ST CH INPUT S

18、T OUT 26 dB RETURN ST OUT 12 dB 2TR INPUT ST OUT 23.8 dB (1 kHz) 入力間 -70 dB 入出力間 -70 dB / GAIN 可変幅 44 dB 0 dBu = 0.775 V 一般仕様一般仕様一般仕様一般仕様一般仕様、 80 Hz 12 dB/octave 、 15 dB ( 最大可変幅) HIGH：10 kHz () / 周波数：最大可 MID：2.5 kHz () 変幅対3 dB 下 LOW：100 Hz () 内蔵 16 、Parameter (ON/OFF) 電源 PHANTOM ON DC+48 V 供給(XLR 入

19、力端子) / PEAK 各：後（、後 MIC 後）信号、手前3 dB 達赤点灯 12- LED 2 ST(L, R) 時：赤色 +5、 +3、 +1、0：黄色 -1、 -3、 -5、 -7、 -10、 -15、 -20：緑色付属品電源(PA-10) (BMS-10A), (FC5) 消費電力 25 W 最大外形寸法（W H D） 251 mm 65 mm 290.5 mm 質量 1.8 kg 0 dBu = 0.775 V 6 MG8 / 2FX 入力仕様入力仕様入力仕様入力仕様入力仕様出力仕様出力仕様出力仕様出力仕様出力仕様入力端子名称入力適合感度*1 最大端子仕様 -60

20、-72 dBu -60 dBu -40 dBu MIC INPUT 3 k 50 600 （0.195 mV）（0.775 mV）（7.75 mV） XLR-3-31 (CH1、2） -16 -28 dBu -16 dBu +4 dBu （型）（30.9 mV）（123 mV）（1.23 V） -34 -46 dBu -34 dBu -14 dBu LINE INPUT 10 k 600 （3.88 mV）（15.5 mV）（155 mV）（TRS）（型 (CH1、2) +10 -2 dBu +10 dBu +30 dBu T：、（0.616 V）（2.45 V）（24.

21、5 V） R：、 S：） ST CH MIC INPUT -60 -72 dBu -60 dBu -40 dBu (CH3(L)/CH4(R)、 3 k 50 600 （0.195 mV）（0.775 mV）（7.75 mV） XLR-3-31 CH5(L)/CH6(R) -16 -28 dBu -16 dBu -10 dBu （型）（30.9 mV）（123 mV）（245 mV） ST CH LINE INPUT -34 -46 dBu -34 dBu -14 dBu (CH3(L)/CH4(R)、 10 k 600 （3.88 mV）（15.5 mV）（155 mV） CH

22、5(L)/CH6(R) +10 -2 dBu +10 dBu +30 dBu （型）（0.616 V）（2.45 V）（24.5 V） ST CH INPUT -22 dBu -10 dBu +10 dBu (CH7(L)/CH8(R) 10 k 600 （61.6 mV）（245 mV）（2.45 V）（型）、 RCA CH INSERT IN -20 dBu 0 dBu +20 dBu （TRS） (CH1、2) 10 k 600 （77.5 mV）（0.775 V）（7.75 V）（型 T：、R：、 S：） RETURN (L、R) 10 k 600 -12 dBu +

23、4 dBu +24 dBu （195 mV）（1.23 V）（12.3 V）（型） 2TR IN (L、R) 10 k 600 -26 dBV -10 dBV +10 dBV RCA （50.1 mV）（316 mV）（3.16 V） 0 dBu=0.775 V、0 dBV=1 V *1 入力感度：最大測定時定格出力得最小出力端子名称出力適合最大端子仕様（TRS） ST OUT (L、R) 150 10 k +4 dBu（1.23 V） +20 dBu（7.75 V）（型 T：、R：、 S：）（TRS） EFFECT SEND 150 10 k +4 dBu（1.23

24、 V） +20 dBu（7.75 V）（型 T：、R：、 S：） CH INSERT OUT （TRS） (CH1、2) 150 10 k 0 dBu（0.775 V） +20 dBu（7.75 V）（型T：、 R：、S：） REC OUT (L、R) 600 10 k -10 dBV（316 mV） +10 dBV（3.16 V） RCA （TRS） C-R OUT (L、R) 150 10 k +4 dBu（1.23 V） +20 dBu（7.75 V）（型 T：、R：、 S：） PHONES 100 40 3 mW 75 mW 0 dBu=0.775 V、0 dBV=1 V 7 M

25、G8 / 2FX DIMENSIONS（寸法図） Unit: mm REVERB HALL 1 REVERB HALL 2 REVERB ROOM 1 REVERB ROOM 2 REVERB STAGE 1 REVERB STAGE 2 REVERB PLATE DRUM AMBIENCE KARAOKE ECHO VOCAL ECHO CHORUS 1 CHORUS 2 FLANGER PHASER AUTO WAH DISTORTION 251 290.5 65 （単位） CIRCUIT BOARD LAYOUT（） REVERB HALL 1 REVERB HALL 2 REVERB

26、ROOM 1 REVERB ROOM 2 REVERB STAGE 1 REVERB STAGE 2 REVERB PLATE DRUM AMBIENCE KARAOKE ECHO VOCAL ECHO CHORUS 1 CHORUS 2 FLANGER PHASER AUTO WAH DISTORTION MAIN DSP 8 MG8 / 2FX PANEL LAYOUT（） Channel Control Section（部） q Channels 1 and 2 (Monaural) Channels 3/4 and 5/6 (Stereo) Channels 7/8 (Stereo)

27、w r t y u e tt yy uu q GAIN Control w PEAK Indicator e Switch (High Pass Filter) r Equalizer (HIGH, MID, LOW) t EFFECT Controls y PAN Controls (CHs 1 and 2) PAN/BAL Control (CHs 3/4 and 5/6) BAL Control (CH 7/8) u Channel LEVEL Control q GAIN w PEAK e （） r (HIGH, MID, LOW) t EFFECT y PAN (CHs 1 and

28、2) PAN/BAL (CHs 3/4 and 5/6) BAL (CH 7/8) u LEVEL Master Control Section（部） REVERB HALL 1 REVERB HALL 2 REVERB ROOM 1 REVERB ROOM 2 REVERB STAGE 1 REVERB STAGE 2 REVERB PLATE DRUM AMBIENCE KARAOKE ECHO VOCAL ECHO CHORUS 1 CHORUS 2 FLANGER PHASER AUTO WAH DISTORTION i w e q u y t r A B C D q PHANTOM

29、+48V Switch w RETURN Control e 2TR IN Control r ST Master LEVEL Control t C-R/PHONES LEVEL Control y Level Meter u POWER Indicator i DIGITAL EFFECT APROGRAM Dial BPARAMETER Control CON Switch DEFFECT RTN Control q PHANTOM +48V w RETURN e 2TR IN r ST t C-R/PHONES LEVEL y u POWER i DIGITAL EFFECT APRO

30、GRAM 選択 BPARAMETER CON DEFFECT RTN 9 MG8 / 2FX Input/Output Section（入出力部） !1 !0 q w ert y oiu qChannel Input Jacks (CHs 1, 2, 3/4, 5/6) MIC Jacks LINE Jacks wINSERT I/0 Jacks (CHs 1 and 2) eChannel Input Jacks (CH 7/8) r2TR IN Jacks tREC OUT(L, R) Jacks yST OUT(L, R) Jacks uC-R OUT Jacks iSEND Jacks

31、 oRETURN L(MONO), RETURN R Jacks !0PHONES Jack !11FOOT SWITCH Jack qINPUT端子 (CH 1, 2, 3/4, 5/6) MIC 端子 LINE 端子 wINSERT I/0 端子 (CH 1, 2) eINPUT端子(CH 7/8) r2TR IN 端子 tREC OUT(L, R) 端子 yST OUT(L, R) 端子 uC-R OUT 端子 iSEND 端子 oRETURN L(MONO), RETURN R 端子 !0PHONES 端子 !11FOOT SWITCH 端子 Rear Section（部） wq qA

32、C ADAPTOR IN Connector wPOWER Switch qAC ADAPTOR IN 端子 w電源 10 MG8 / 2FX Connector Polarities MIC INPUT Pin 1: Ground Pin 2: Hot (+) Pin 3: Cold (-) LINE INPUT (monaural channels), ST OUT, C-R OUT EFFECT * Tip: Hot (+) Ring: Cold (-) Sleeve: Ground Tip: Output Ring: Input Sleeve: Ground PHONES Tip: L

33、 Ring: R Sleeve: Ground RETURN, LINE INPUT (stereo channels) Tip: Hot Sleeve: Ground INPUTOUTPUT SleeveTip Ring SleeveTip * These jacks will also accept connection to monaural phone plugs. If you use monaural plugs, the connection will be unbalanced. MIC INPUTINSERTININIININSERT I/OINSERT I/O Sleeve

34、Tip 端子、端子使用。場合、。 MIC INPUT ：： (+) ： (-) LINE INPUT （）, ST OUT, C-R OUT EFFECT ： (+) ： (-) ： INSERT I/O ：Output ：Input ： PHONES ：L ：R ： RETURN, LINE INPUT （）：： INPUTOUTPUT 端子接続極性 11 MG8 / 2FX DISASSEMBLY PROCEDURE（分解手順） 1.Bottom Case(Time required: About 1 minute) 1-1Remove the two (2) screws mark

35、ed 260.(Fig.1) 1-2Remove the five (5) screws marked 265 using a hexagonal wrench.(Fig.1) Note: The spacers 160 have been attached to the five (5) screws marked 265 respectively. Be careful not to lose the spacers while disassembling.(Fig.2) 1-3Under such a condition, lift the top cover up. The botto

36、m case (with the sheet shield 8 and the support stand) can then be removed.(Fig.1) *Remove the two (2) screws marked 240. The bottom case, the sheet shield 8 and the support stand can then be separated. (Fig.1) (Fig.1) 240: Bind Head Tapping Screw-S 3.0X6 MFZN2BL(EP630210) 260: Bind Head Tapping Scr

37、ew-B 3.0X8 MFZN2BL (EP600190) B 265: Cap Screw 3X25 MFZN2BL (WD251500) 6角孔付P 265 MAIN Circuit Board （MAIN） Top Cover （） 160 160: Spacer MG8/2FX (WD237400)MIX 265: Cap Screw 3X25 MFZNBL (WD251500) 6角孔付P (Fig.2) 2.DSP Circuit Board (Time required: About 3 minutes) 2-1Remove the bottom case.(See proced

38、ure 1.) 2-2Remove the one (1) screw marked 263, and pull out the power switch and AC connector from the holes on the rear panel.(Fig.3) 2-3Turn the unit upside down. 2-4Remove the two (2) screws marked 130. The shield cover can then be removed.(Fig.4) 2-5Remove the four (4) screws marked 110, and pu

39、ll out the connector CNM02 (on the DSP circuit board) from the connector CNE01 (on the MAIN circuit board).(Fig.4) 260 265 265 265 265 265 Bottom Case （） Top Cover （） 240Support Stand （） Sheet Shield 8 （8） 1.（所要時間:約 1 分） 1-12602 本外（Fig.1） 1-22655 本六角外（Fig.1）注）2655 本160 付作業時無様注意下（Fig.2） 1-3状態部分上

40、持上（ 8、付）外（Fig.1） *2402 本外、 8、分離。 (Fig.1) 2.2.2.2.2.DSPDSPDSPDSPDSP （所所所所所要要要要要時時時時時間間間間間: : : : :約約約約約 3 3 3 3 3 分）分）分）分）分） 2-1外（1項参照） 2-22631 本外電源AC 側穴外（Fig.3） 2-3本体逆 2-41302 本外外（Fig.4） 2-51104 本外（CNM02） MAIN 上（CNE01）抜 DSP外（Fig.4） 12 MG8 / 2FX 130 DSP Circuit Board （DSP） MAIN Circuit Board （

41、MAIN） Cover （） Shield （） 110 Connector CNM02 （CNM02） Connector CNE01 （CNE01） Power Switch and AC Connector （電源AC） 263 Top Cover （） 263: Bind Head Tapping Screw-S 3.0X6 MFZN2BL (EP630210) S (Fig.3) 110: Bind Head Tapping Screw-S 3.0X6 MFZN2BL (EP630210) S 130: Bind Head Tapping Screw-S 2.6X4 MFZN2Y (

42、VU757900) S (Fig.4) 3.MAIN circuit board (Time required: About 14 minutes) 3-1Remove the bottom case.(See procedure 1.) 3-2Remove the one (1) knob (red) marked 200.(Fig.5) 3-3Remove the seven (7) knobs (white) marked 190.(Fig.5) 3-4Remove the one (1) knob (gray) marked 300.(Fig.5) 3-5Remove the one

43、(1) screw marked 263, and pull out the power switch and AC connector from the holes on the rear of the top cover.(Fig.3) 3-6Remove the eight (8) screws marked 180a.(Fig.5) 3-7Remove the two (2) screws marked 180b.(Fig.5) 3-8Remove the nineteen (19) sets of the hexagonal nut and washer using a box wr

44、ench.(Fig.5) 3-9Lift up the top cover to remove the MAIN circuit board.(Fig.2) Note: A guard has been attached to the place of PHAN- TOM +48V on the top cover. Be careful not to lose the guard while disassembling.(Fig.5) 3-10Remove the DSP circuit board. (See procedure 2 (2-3 to 2-5).) 3-11Remove th

45、e two (2) screws marked 80.(Fig.6) 3-12Remove the two (2) plastic rivets marked 90.(Fig.6) 3-13Pull out the two protruding portions of the shield from the holes on the MAIN circuit board. The shield can then be removed from the MAIN circuit board.(Fig.7) 3.3.3.3.3.MAINMAINMAINMAINMAIN （所所所所所要要要要要時時時

46、時時間間間間間: : : : :約約約約約 1414141414 分）分）分）分）分） 3-1外（1 項参照） 3-2200（赤）1個外（Fig.5） 3-3190（白）7個外（Fig.5） 3-4300（灰）1個外（Fig.5） 3-52631 本外電源AC 側穴外（Fig.3） 3-6180a8 本外（Fig.5） 3-7180b 2本外（Fig.5） 3-8六角19 外（Fig.5） 3-9上持上MAIN外（Fig.2）注）PHANTOM 48V位置取付作業時無様注意下（Fig.5） 3-10DSP 外（2項 2-3 2-5 参照） 3-1180 2本外（Fig.6） 3-1290 2個外（Fig.6） 3-13突起部分 2箇所 MAIN 穴抜外（Fig.7） 13 MG8 / 2FX 200 300 180a 180b 190 Guard （） Hexagonal nut & Washer （六角、） Top Cover （） 180: Bonding Tapping Screw-B 3.0X10 MFZN2BL (VQ049800) B 190: Knob WHITE/M-GLAY (WA009900) LEVEL 200: Knob RED/M-GR