Fisher MT-750 User manual

~ 134 080
50

CONTENTS
Arm Feed Cord Stringing ............ cece cece cece eee e cece cnet e ee en tent ee en eneeeneneeenes 2
SpeCitiCavOnS-sicctiwkcicessncte ca dese ue lave noore vosdpe vainseeabadeh enero bateee eanuiaers 3
Semiconductor Lead identification ............ 0... ccc cece cece eee e nee e eee e ee eee eens 4
IC Signal Flow & Equivalent Circuit ..........0.... ccc ccc cece een eens 5,6
Cabinet & Turntable Exploded View .............. 0c cece cece cece een e tee eeeeeeenenes 7,8,9
Cabinet & Turntable Parts List .............. 0... c cece cece cece eee ene eee eeeeeeeeeee 10,11
Functional Description ...............c cee cece eee e ene e nee e eee ener enn ene en eeeeee 12,13,14
Adjustment Procedures .......... 0. ccc eee ete e eee e erence een ene n en ees 15,16,17
P.C.Board Parts List ............ccccccenccccccccncacacenccnesencusecurccscesusvecs 18,19,20
Printed Circuit Board (Bottom View) ...............c cece cece ence ee ee 21,22,23,24,25,26
Schematic Diagram .............: ccc cece cece cece eee ete eee en eee tere e ee ne nena 27,28
Point to Point Wiring Diagram ............. cc cece e eee eee ee n eee e een een eee e es 29,30
Motor Assy Schematic Diagram ............... cece cece cece eee e ete e eee eee ee aee 31
Motor Assy P.C.Board (Bottom VieW) ........... 0c cece cece cece nnen eee eeeeeenneees 31
ARM FEED CORD STRINGING

SPECIFICATIONS
Motor Quartz Locked FG Servo
Direct
Drive System
Wow and Flutter (WRMS) 0.035 %
Rumble (DIN 45539B) —70dB
+1.5%
29g
12-1/8"
Speed Variation
Tracking Force
Platter Diameter
Platter Weight 1.4 Ibs.
Record Speed Selector 33-1/3 rpm/ 45 rpm
Auto Function
Start Yes
Repeat Yes
Reject
Automatic Tonearm Return at End of Record
Yes
Start Yes
Yes
Stop
Tonearm Data
Resonance <18Hz
Shape Straight
Pivot
0.15 g
Pivot
0.2g
Max. Tracking Error | +0.2°
Bearing Type
Horizontal
Friction Sensitivity
Vertical
Friction Sensitivity
Cueing Motor Drive
GENERAL
Power Requirements (50 Hz)
AC 110/220V
440 x 98x 355 mm
5 kg
Because its products are subject to continuous improvement, Fisher Corporation reserves the right to modify
product designs and specifications without notice and without incurring any obligation.
Power Consumption
Dimensions (W x H x D)
Weight (approx.)

SEMICONDUCTOR LEAD IDENTIFICATION
INTEGRATED CIRCUITS
@ NJM 7812
@ NJM 7912
e | 78M05
8
@ MSM 4049 RS © LA6324
TRANSISTORS
DIODES
e DS135D

IC SIGNAL FLOW & EQUIVALENT CIRCUIT
LM 6402A
Plo-2 <=> i
ac
a ae (a
=
pHo.s <Y PORT. RAM 3 <j ROM
H a
a
fi
PORT
f
d
PGo-3 CAs Ly i} |
IT
Pos a FA
PLAo- {
cee ca PoRT|
ee ed feed eee ae
INTERRUPT iNT
-_—O RES
¥ 3 y 3 u 0-3 sO Xtal
=O EXtal
—™-O Vobo
=O Vss
NJM 7812, L 78 MOS
3IN
O 1 OUT
4—o 2GND
NJM 7912
~) 3 GND
—O 21N

IC SIGNAL FLOW & EQUIVALENT CIRCUIT (continuea)
LA 6324
TOP VIEW
|
Oo
MSM 4049 RS
NC NC
6 15 14 13 l2 HH W 9g
1 2 3 4 5 6 7 8
vt GNO

CABINET
&
TURNTABLE
EXPLODED
VIEW
(1)
CABINET
&
TURNTABLE
EXPLODED
VIEW
(2)
CA21
CA21
eS CA96
an CA97
CAg0
©—caal

CABINET
&
TURNTABLE
EXPLODED
VIEW
(3)
CASI a
$
SS eas
c461 4 oar GAGS cA24 —o\->——CA89
e— U6 cA70
|
—_ t= CA56
¢——caTl
¢——Ca2d
CAT3
cas2 CAsd—O sis
G
Ss ar
CA93
CABINET & TURNTABLE PARTS LIST
net: Part No. Description Q’ty fet:
PACKAGE CA27
131 2 3901 10300 StapleSSi9MM 8 CA28
131 6 2519 00201 Bag Polyethylene Ind 1 CA29
131 6 3069 17500 Patching Sheet 1 CA30
131 6 4159 10106 Notes 3 CA31
131 6 4559 10900 Manufacturing No. 2 CA32
134 2 2104 12300 Screw Transit(+,-) 3 CA33
134 2 4208 15100 Spacer 3 CA34
141 2 4219 32700 Screw Transit 1 CA35
141 6 1139 98402 Box Corrugate-exp 1 CA36
141 6 2519 19490 Bag Polyethylene-exp 1 CA37
141 6 3119 23401 Pad 1 CA38
141 6 3119 24900 Pad Front 1 CA39
141 6 3119 25000 Pad Rear 1 CA40
141 6 3119 25100 Pad 1 CA41
CA42
CA43
ACCESSORIES CA44
4 2369 74031 Plug Cord 1 CA45
131 2 3901 10400 Staple No.10 1 CA46
131 6 2719 10801 Bag Fan 1 CA47
131 6 4519 15700 Guarantee Cert 1 CA48
131 6 4559 10900 Manufacturing No 1 CA49
134 2 2901 11601 Adapter Ep 1 CA50
142 6 4119 32156 Explanatory Booklet 1 CA51
CA52
CA53
CABINET CA54
4 2359 75222 Connector 12P Assy [CN9] 1 CA55
4 2359 76794 Connector 3P Assy [CN13] 1 CA56
4 2359 77145 Connector 1P Assy 1 CA57
4 2359 77631 Connector 1P Assy 1 CA58
131 2 1310 34634 Name Plate 1 CA59
131 2 3608 14100 Cramp Wire 4 CA60
131 2 7103 46800 Label 1 CA61
131 2 7103 47900 Label 1 CA62
131 6 4559 10900 Manufacturing No 1 CA63
141 6 4729 37447 — Stylus Label 1 CA64
CAI 141 0 1249 30600 Lid Assy 1 CA65
CA2 = 131 0 2002 16800 Hinge Assy 1 CA66
CA3 141 2 4429 00201 Mat Turntable 1 CA67
CA4 =: 141. 2 5229 00401 ~— Turntable 1 CA67
CA5 =: 131. 2 4201 20702 = Screw, +M3.0x35 5 CA68
CA6 141 2 1219 29500 Panel Front 1 CA69
CA7 = 141. 2: 1329 14200 Filter 1 CA70
CA8 131 2 6113 51000 Shelter 1 CA71
CAQ 131 2 6113 51100 Shelter 1 CA72
CAIO = 141 2 1329 14300 Filter 1 CA73
CA11 =141 2 1439 14100 Panel Control 1 CA74
CA12 AX 4 2432 00071 ~~ Power Cord 1 CA74-1
CA13 131 2 6111 21300 Bushing 1 CA74-2
CA14 141 2 1659 35600 Knob 1 1
CA15 141 2 1659 35800 Knob 1 2
CA16 131 2 4201 21100 Screw 7 CA74-3
CA17 = 131 0 4004 16101 Wire Shield Assy 1 CA75
CA18 141 2 1439 13900 Panel Control 1 CA76
CA19 131 2 2904 11000 Pad Lid 2 CA77
CA20 131 2 4201 20705 Screw, Bdg Hd. Tapping 14 CA78
CA21 131 2 4201 23703 Screw 6 CA79
CA22 141 2 1129 08801 Cabinet 1 CA80
CA23 141 2 1149 37400 Cover PCB 1 CASI
CA24 131 2 4201 19501 Screw, Button Hd. Tapping 19 CA82
CA25
134
0
5011
03600
Motor
Assy
(Phono)
[M1]
1
CA83
CA26 141 2 4459 31800 Cushion 4 CA84
!
ary °o
I
Part No.
141 2 3719 06200
131 2 4201 25205
A 4 2512 30420
131 2 3608 12405
134 2 4201 13400
141 2 1149 39400
131 2 4201 20801
AX 4 2312 06051
131 2 4201 20300
131 2 4203 84507
131 2 1601 85202
131 2 3608 11000
141 2 4419 21100
134 2 5205 12000
131 2 1601 59501
131 2 4201 24600
141 2 1659 35700
141 2 1259 07300
141 2 8559 06505
141 2 4459 31700
131 2 5203 23603
141 2 8559 06506
141 2 8559 06501
141 0 3129 01900
141 2 4459 33800
141 2 8519 31900
141 2 3519 67400
141 2 8539 53800
131 2 4201 20800
131 2 4201 19500
131 2 4201 19504
141 0 5519 10300
141 2 5649 22600
141 2 8519 60000
134 2 4201 12800
141 2 7519 64000
141 2 5519 52100
141 2 3519 67100
141 2 4459 31800
4 5272 00181
4 2319 76680
4 2319 76680
141 2 3519 66900
141 2 3519 67500
141 2 3519 66800
141 2 4219 06300
134 2 5101 32400
141 2 3519 67000
141 0 6419 01200
141 0 6419 01300
4 1579 70030
4 1579 70040
4 1579 70050
141 2 6459 00300
134 2 5101 26500
141 2 4579 05000
141 2 3519 70300
131 2 4112 10200
141 2 7319 58000
134 2 4106 27000
141 2 5519 52200
141 2 5649 24700
141 2 5739 07000
131 0 3020 11800
Description
Metal Mount Trans
Screw
Power Trans [T1]
Cramp Wire
Screw
Cover
Screw, +M2.6x8
Switch Push Power [S4]
Screw TP
Washer Plain, M4.5x10x0.5
Knob Power
Cramp Wire
Cloth
Cushion
Knob
Screw
Knob
Plate Bottom
Spring Mounting
Cushion(Leg)
Felt
Spring Mounting
Spring Mounting
Unit Plate Assy
Cushion
Spring, Slide Base
Angle Mount(Photo C)
Spring Plate
Screw, +M2.6x6
Screw, Button Hd. Tapping
Screw, Button Hd. Tapping
Worm Assy
Belt
Spring Plate
Screw
Spindle Lifting
Worm Wheel(A)
Angle Mount(Metor)
Cushion
Comutate MTR Magnet (Arm) [M3]
Leaf Switch (Lift Up) [$1]
Leaf Switch (Lift Down) [S2]
Cover(Holder)
Plate(Filter)
LED Holder
Screw
Spring
LED Holder Base
Pick-up Assy
Tone Arm Assy
Cartridge Assy
Cartridge (MG-102S)
Stylus (ST-102SD)
Retainer Needle
Spring
Washer, M3.2x10x0.2
Angle Mount
Rope
Holder Slide
Shaft
Worm Whell(B)
Belt
Support Shaft
Pully Assy
Q
Ca
we
a ne ee a CS as Oe Cs Ca CC CE SS RDN CET EE, we Oe CC CC rT Ss Os Sar CE CE, SG a ee ee
wonwrnAa oe

CABINET & TURNTABLE PARTS LIST (continuea)
Ret.
Part
No.
Description
Q'ty
CA85 141 2 3519 69000 Angle Mount
CA86) «141 2 8519 33300 Spring, Lock Caset Case
CA87 =141 2 3169 23200 Frame
CA88 =141 2 3519 69100 Angle Mount
CA89 141 2 4459 33200 Cushion
CA90 «141 2 5289 01600 Rail
CA91 4 2319 77560 Leaf Switch (Return) [S3]
CA92 141 2 3169 22200 Guide Angle
CA93. 141 2 3519 72200 Angle Mount
CA94 141 2 125907401 —‘ Plate Bottom
CA95 4 5272 00180 Comutate MTR Magnet (Lifter) [M2]
CA96 §=131 2 4201 20300 Screw
CA97? =: 131 2 7104 00101 Plate Pad Switch
CA98 AX 4 2312 02650 Switch Slide (Voltage Select) [$5]
Sa er a es Cw NG
Cx1 101 3 1302 00311 Screw, Pan Hd., +M2.0x3
CX2 ~=—s- 101 3 1303 03011 Screw, Pan Hd., +M3.0x30
Cx3 103 3 1303 00511 Screw, Pan Hd. Tapping-2, +M3.0x5
CX4 103 3 1904 00611 Screw, Brazier Hd. Tapping-2, +M4.0x6
CX5 143 3 1702 00618 Screw, Bind Hd. Tapping-B, +M2.0x6
CX6 143 3.1702 00818 Screw, Bind Hd. Tapping-B, +M2.0x8
CX7 =—s- 112 3. 1302 00011 ~~ ERing, M2.0
CX8 110 3 2104 00011 Spring Washer-2, M4.0
CX9 = =106 3 1204 00311 Hex. Nut-2, M4.0
-—-3 43 po |SHNDO DP HS
PCB1 141 0 1939 05800 Control P.C.B. Assy
PCB2 141 0 193902710 PCRP.C.B. Assy
PCB3 141 0 1939 02721 PTRP.C.B. Assy
PCB4 141 0 1939 02731 LED P.C.B. Assy
PCB5 1414 0 1939 05471 —‘ Terminal P.C.B. Assy
PCB6 141 0 1939 05900 Sub Control P.C.B. Assy
PCB7 141 0 1939 06000 Touch Switch P.C.B. Assy
PCB8 141 0 1939 06100 Manual Switch P.C.B. Assy
PCB9 141 0 1939 06200 Slide Switch P.C.B. Assy
PCB10 141 0 1939 06300 Auto Function Jack P.C.B. Assy
PCB11 141 0 1939 06500 Power Supply P.C.B. Assy
—- oS oi ss
NOTE:
1. Parts order must contain Model Number, Part Number and
Description.
2. Ordering quantity of screws and resistors must be multiple of
10 pcs.
PRODUCT SAFETY NOTICE
Each precaution in this manual should be followed during servicing. Components identified with the IEC symbol A\ in the
Parts list and the schematic diagram designate components in which safety can be of special significance. When replac-
ing a component identified with A\ , use only the replacement parts designated, or parts with the same ratings of resis-
tance, wattage or voltage that are designated in the parts list in this manual.
Leakage-current or resistance measurements must be made to determine that exposed parts are acceptably insulated
from the supply circuit before returning the product to the customer.
-11-

FUNCTIONAL DESCRIPTION
MICROCOMPUTER PORTS AND FUNCTIONS
INTRO LED ay TR-7 LED
TR-9 LED a TR-8 LED
Lift Down SW. ;
Lift Up SW. - Phono Motor
Speed
PBo~PB2 Arm Position
Arm Motor (left) ..ON
PCo~PC3 Key Scan Arm Motor (right) ..ON
PDo~PD3 Key Scan
Lifter Motor (down) ON
PEo TR-1 LED as Lifter Motor (up) ON
PE1 TR-2 LED “as Muting Relay ..ON
PE2 TR-3 LED ei Repeat ..ON
PE3 TR-4 LED
Reflector .. reflected
PFo TR-5 LED ae Back Pulse for Jeadin . OFF
PFi TR-6 LED ns Signal (sound) .. signaled
Xtal (1 EXtal
PCo [J 2 VDD (+5V}
PCi CJ3 PB3
Pc2 (4 PB2
Pc3(J5 PB1
iNT (6 PBo
RES(J7 PA3
PDo[]8 PA2
PD1[]9 PAI
PD2([]10 PAO
PD3(_J]11 Pl2
PEo(PLAo){_}12 Pit
PE1(PLA1) Pio
PE2(PLA2)(] 14 PH3
PE3(PLA3) (J 15 PH2
PFo(PLAa){_]16 PH1
PF1(PLA5){ 417 PHo
PF2(PLA6){_J18 PG3
PF3(PLA7)[_J19 PG2
TEST PG1
(OV) Vss ([] 21 PGo
-12-