Manual: EC100 SM NAKAMICHI EN - archive.org

Nakamichi

Service Manual

Nakamicni BlackBox Series PS-100

SF-100

LA-100

BA-150

MB-150

EC-100

MX-100

Power Supply

Sub-sonic Filter

Line Amplifier

Bridging Adaptor MC Booster Amplifier

Electronic Crossover

Microphone Mixer .

CONTENTS

1. PS-100 Power Supply .u...cc.cccsscccsseccsnscnsessnscccssenserancesseeasercnenanss Gites seus tvae Don ates futheneacumauteceannted seal actetadat bacae Sunaecuancnens 1

General, Mute Signal, Specifications, Schematic Diagram, Mounting Diagram

and Parts List, Mechanism Ass’y and Parts List

2; SF-T00 SUD-SOMICG: FIlteh suaccedisedeapeawentecent ovescddvaeaneccuecnG cue cose henccan ceuapeadeecCacdsseawesenceis sncsedsueovsssacc sen sncbuoassupsdeaeaseesersentes 5

General, Specifications, System Diaper. Schematic Diagram,

Mounting Diagram and Parts List, Mechanism Ass’y and Parts List

3. LA-100 Line Amplifier _........ ss Sasealansbeicise dcid bine naam aioe aean'v obunwaawunendandeceaducstlemeds oveeGonadaaeedeckcncskueasensacscaiiesccswasuwusastaencweateerss 8

General, Specifications, System Diagram, Schematic Diagram,


4. BA<150 Bridging: AGatOr® «cccsisscssscsnsickssstsccevsteessiadsed ves cdecdencaescengeseediative si scsevdicnbesceavcddesusupsaccsasccqdecaseebenacekeonsewvresens: 11



5. MB-150 MC Booster Aniplifier. -cciicccsvercsecsccvsteisncriduswosidnsvesedsseeceasnuscssdvadectesdavsveatooacsoneusuedaaeneansaanaseianme cnnoasarateoteeder 14



6. “EG 100 Eleetronie CrossOver -sciissceccddccccisaicucaassccceesaeecianaasoiaunesniaccantiuedeacaasssesasuatenededsccpvevetecscascacisecewecswanasenseatoeeries 17



7c (NDE TOO Microphone MIXCh isis cccccicccicswosescccccstacvessdersssonedenddsinnaalsnneedvep sane resteccsnsioancasaserdsscascneceussetonadsbecasuerswwseetee 20

General, Specifications, System Diagram, Seemae Dieacsn)


1. PS-100 POWER SUPPLY

General As a result, 0413 turns on and the mute signal is changed

PS-100 Power Supply

PS-100 is a regulated power supply unit designed to be a

power supply for the BlackBox Series (the rated output

current: £200 mA).

Although PS-100 is provided only with one output termi-

nal, two input/output terminals on the other units of the

BlackBox Series make multiple connection of PS-100

possible.

To prevent noise signal generation on switching ON/OFF

the power supply, PS-100 produces a mute signal, muting

output terminals of each unit furnished with a muting

circuit.

Refer to Table 1 showing how many units of the Black-

Box Series can be driven by a single PS-100.

Mute Signal

Mute signal is muted for a certain period of time to

prevent transient noise when power is ON or OFF.

Power ON

Transformer output is rectified through diode D403 and

smoothed by capacitor C408. Therefore, positive poten-

tial appears at C408 (transistor Q411 base). Accordingly,

0411 is in the cutoff state. C409 (22 uF) is charged with negative potential through R414 (1 M2), therefore at the

level where the voltage across C409 exceeds Vbe (base-

emitter voltage) of 0412, Q412 turns from OFF to ON.

from + V to —10 V, releasing the mute state. (The mute time depends on C409 and R414 after power is

ON.)

Power OFF

Transformer output becomes zero and so C408 is charged

with negative potential through R415. At the level where

the voltage across C408 exceeds Vbe of 0411, 0411 turns

from OFF to ON and C409 is quickly discharged. Thus,

Q412 is cut off and 0413 is also cut off. Therefore

the mute signal becomes + V (i.e. mute state). D402

acts to prevent + V from being discharged easily when

power is OFF.

Specifications Maximum Power Consumption... 20VA

Output Voltage. .........4.. +10V

Rated Output Current ........ + 200 mA

Dimensions .........-.0068:5 7-1/2(W) x 2-3/8(H) x 3-15/16(D) inches 190(W) x60(H) x 99(D) mm

W6IGNT 4.6.4 ne Sal ee ae aa re, Ee 3.5 lb, 1.6 kg

Table 1 Combinations of Units Driven by a single PS-100

LA-i00 BA-150 MB-150 EC-100 MxX-100

Sub-sonic Line Bridging MC Booster Electronic Microphone Filter . Amplifier Adaptor Amplifier Crossover Mixer

0.5 VA 1 VA 2 VA 1 VA 2 VA

(+25 mA) (+50 mA) (£100 mA) (£50 mA) (£100 mA)

Combination

a |

Maximum

Drivable

Number

of Units

ie) $ N

Schematic Diagram

MUTE

Q402 280235

C404 470 25V 120V. T1”

BRN YEL

M3 5P Terminal

O

i C402

100 25V C405 220u 25V

Power Switch

M2

Spark Killer Wl ozo

AC INPUT 120V~

Q405 U.S.A. /CANADA BLK 2$¢945

VERSION aaa A se

a Zs) | 1. i ea ee a [EUROPE VERSION, ———=<“C—s=i‘—S*~C~SSSCO 1 [JAPAN VERSION oy vey |

| 4 | | | | |

| is 3. | | | | sy ate ; | g aut :

3 Ss

| f 8 | | : | |

AC INPUT | 220V~ | | YEL |

L J L ee eee

Notes: 1. Fuses marked with «1 are not incorporated in the U.S.A. version.

2. The type of spark killer marked with *2 differs in some countries.

Mounting Diagram and Parts List

Schematic oie Schematic .

Serematie | pane, | Deserition

PS-100 P.C.B. Ass’y

0401,407

408,410

411,412

Q402

0403 ,404

405,409

413

0406

D401

D402,403

2D401

R 401,409

419

R402,408

R403

R404

R405,411

R406

R407

R410,418

R412

R413

R414,416

R415

R417

C401,403

C402 ,404

BA03855A

0B07720A

OBO6013A

0B01823A

0B01872A

0B06011A OB06088A 0B01909A OBO6063A 0B01781A

OB05824A OB05673A OBO5664A 0B05746A 0B01793A OBO5826A 0B01833A OBO5596A OBO5563A OBO5564A OB05674A 0B01921A 0B01401A

0B01272A

Power Supply P.C.B.

Transistor

Transistor

Transistor

Transistor

Silicon Diode

Silicon Diode

Zener Diode

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

2SA733

2SD235 (Y)

2SC945

2SB435

SiIRBA

181555

YZ040B

1K

4.7M

5.6K

3.9K

1

3.3K

11K

10K

220K

56K

1M

820K

330K

Electrolytic Capacitor

470u


100u

ERD-25V J

ERD-50T J

ERD-25V J

ERD-25V J

ERD-25V J

ERD-25V J

ERD-25V J

ERD-25V J

ERD-25V J

ERD-25V J

ERD-25V J

ERD-25V J

ERD-25V J

25V

25V

C405

C406 ,407

C408

C409

OBO1391A

OBO01502A

0B01780A

OB05820A

0J03597B

OEO0607A

OE00507A


220


330u

Mylar Capacitor 0.1


22u

Heat Sink (1 pce.)

Screw M3x8 Philips Pan Head

(3A) (4 pes.) Nut Hex. M3 (2 pcs.)

25V

16V

50V J

16V M

(MS)

Mechanism Ass’y and Parts List

PS-100 Mechanism

OHO3509A

OM03799A

OMO3800A

BA03855A

0B08161U

OB06567A

OBO6568A

O0B08025U

OB08355A

0B07172A

0B07092A

0B08037A

OBO08351A

OB08325A

OB08350A

0B08219B

OB08348A

OB08149U

Notes: 1. 02, 08, 09 and 10 differ in versions.

2. 04 (fuse) is not incorporated in the U.S.A. version.

Upper Cover PS

Caution Label G

Caution Label H

PS-100 P.C.B. Ass’y

Fuse 630 mA

Power Transformer 100—120 V

Power Transformer 220—240 V

5P Terminal

4P DIN Socket

Power Switch

Power Switch

Cord Bushing

Cord Bushing

Cord Bushing

Power Cord

Power Cord

Power Cord

Power Cord wed wh eke ed ed etd etd eA) wd td

Fig. 1.3

Schematic ' ee

HA03697C

0H03437A

OBO8361A

OB08363A

OB08342A

0B08240A

O0BO07096U

0E00713A

OEOO606A

OE00538A

OE00594A

OE00714A

OEOO651A

OE00593A

OE00157A

Main Chassis PS Ass’y

Rubber Foot

Spark Killer 125 V (R + C) Spark Killer 125 V (R + C)

Spark Killer 125 V (R + C)

Spark Killer 250 V (R + C)

Spark Killer (C) Screw M3x6 Philips Truss Head


(3A) Screw M4x5 Philips Binding

Head |

Screw M3x8 Philips Binding

Head

Screw M2.6x6 Philips Binding

Head

Washer 2.6 mm (plastics) Screw M3x6 Philips Binding

Head

Washer 3 mm (plastics)

Oop-erFr Fee FO

2. SF-100 SUB-SONIC FILTER

General Specifications

In disc record reproduction, low-frequency resonance ofa Maximum Power Consumption... 0.5 VA

tone arm and rumbling of a turn table exist at about 10 Zaet Consumption ........ ue = eee ‘ : Total Harmonic Distortion ..... ess than O. 6 zZ—

Hz and their peak level ranges approximately from 5 to 15 20 kHz, 1 V Output)

dB. Frequency Response......... 40 Hz — 100 kHz + 0.5 dB

SF-100 is an active filter to eliminate these noises. Sub-sonic Filter. .........-. 10 Hz: —50 cB,

The unit is designed so that no low frequency sound —40 dB (with Low

recorded on disc records is sacrificed and no change in Boost) t ‘nt tSctaG Low Boost: <a 44.5 Whe ee ews 30 Hz: + 5 dB

COE re ; ; _ Signal-to-Noise Ratio ........ better than 110 dB (IHF-A

To compensate the personal feeling of insufficiency in low Network)

frequency sound caused by the insertion of the Sub-sonic Mute Function ............ Furnished

Filter, a Low Boost Switch is provided which can boost Dimensions ...........55. 7-1/2(W) x 2-3/8(H) x

signal approximately by 5 dB at 30 Hz. 4-1/16(D) inches With both of the Fil Switch and L B, 190(W) x 60(H) x 103(D) mm

ith both of the Filter Switch and Low Boost Switch Weight... 2... eee eee eee 2.7 Ib, 1.2 kg turned OFF, the input signal directly appears on the

output terminals without passing through the Sub-sonic Filter. | System Diagram

ea

The output of the twin-T filter is amplified by Amplifier aad 2, while the output of the amplifier is positively fed back fags | Output

through C, and Rz to compensate the level reduction in C bos : > ©)

the range of 20—50 Hz. ee ps |

Further, to increase the attenuation below 5 Hz, the filter | | K)

load impedance is lowered with R,, and the improvement ; Out a See eae eee ind

of characteristics can be realized by changing impedance | OF ne out of of every device. | _ouut Mute Switch

In addition, a high pass filter is incorporated in the input Oln

side of Amplifier 1 to ensure an ideal sub-sonic filtering ____ Low Boost Switch

characteristics. Fig. 2.1

Schematic fos Schematic ae

Seramate | pane, | Description Sorts | raewo, | Deserintion

BA03849A_ | SF-100 P.C.B. Ass’y R114,115 | OB05562A Carbon Resistor 47K ERD-25V J

119,214

0B07719A SF P.C.B. 215,219

Q101,102 | OBOGO62A Transistor 2SC1222 (2) R116,216 | OBO5678A Carbon Resistor 560 ERD-25V J

201,202 R117,118 | OBO5567A Carbon Resistor 33 ERD-25V J

Q103,104 | OBO6013A Transistor 2SA733 217,218

203,204 C101,201 | OBO5682A Mylar Capacitor O.068yu 50V J

Q105,205 | 0B01872A_ | Transistor 280945 (L) C102,202 | 0B01863A_ | Electrolytic Capacitor D101,102 | OBO01909A Silicon Diode 181555 3.3u 16V

103,201 C103,105 | OBO5844A Mylar Capacitor 0.33u 50V J

202,203 203,205

R101,201 | OBO5700A Carbon Resistor ERD-25V J | C104,204 | 0B05832A Mylar Capacitor 0.0184 50V J

R102,202 | OB05564A Carbon Resistor ERD-25V J | C106,206 | OBO5639A Electrolytic Capacitor

R103,203 | OBO5563A Carbon Resistor ERD-25V J 1.54 35VM

R104,204 | OBO5608A Carbon Resistor ERD-25V J . (MS)

R105,205 | 0B01789A Carbon Resistor ERD-25V J | C107,108 | OBO5884A Electrolytic Capacitor

R106,206 | OBO5664A Carbon Resistor ERD-25V J 207,208 470u 10V

R107,207 OB01564A Carbon Resistor ERD-25V J O0B07167A Push Switch (1 pce.)

R108,109 | OBO01921A Carbon Resistor _ ERD-25V J | CN1 OB08182A 6P-T Post

208,209 CN2 OB08236A 4P-T Post

R110,210 | 0B01795A Carbon Resistor ERD-25V J

R111,211 0B01902A Carbon Resistor ERD-25V J

R112,212 | OBO5569A Carbon Resistor ERD-25V J

R113,213 OBO5565A Carbon Resistor ERD-25V J

Schematic Diagram

POWER S.F. P.C.B. R33. oN ey RED INPUT

CN-1 — §68bu YEL 5 Inpur OJ (1) Zi=50KQ -x ree:

ee ear 9 « & bed

BLK re)

6 R102 1M

LEFT

0 lout DIN JACK POWER

Fo O-IN e 3 | OUTPUT OUTPUT (C nae Ri09

o OUT at? 8 = ByOK 330K On woxe”

IN ec” Om ine)

ouTPuUT (©) 6)— | = Zo=5602 r PIN | RI=10KQ MUTE

R119 D103 Ig le 181555 47K sis No

J ziss :| 8 mit al? 9.8V Baas : \s

CN-I4 1c201 a 204 INPUT = (@}-8LY-G) K

Zi=50KQ = fe |

ia | 83 Ls BLK (4) ie

: RIGHT |

| OUT

IN

ouTPUT (©) OUT

6 O— IN es

ouTPUT (OF (6) Zo=5602 be IN RI=10KQ “1 — 5

D101 1S1555

C103 0.33, Ge. C203 0.33ud C105..0.33yJ

ee

Fig. 2.3


Fig. 2.4

i . . ti

i i ‘

| SF-100 Mechanism OE00157A Washer 3 mm (plastics) 7

OEOO606A Screw M3x6 Philips Pan Head

OHO3507A Upper Cover SF 1 (3A) BAO3849A SF-100 P.C.B. Ass’y 1 OE00612A Screw M3x6 Philips Pan Head

0J03654B Front Chassis 1 (2A) JAO3061A Push Button Ass’y 2 OE00507A Nut Hex. M3

0J03440A Switch E Block Base 1 OE00037A Earth Lug B-5

0B08290B 6P Pin Jack 1 OEO00594A Screw M3x8 Philips Binding

0J03277A Metal Seat Nut 2 Head

OBO8355A 4P DIN Socket 2 OE00714A Screw M2.6x6 Philips Binding

OHO3508B Main Chassis SF 1 Head

0H03437A Rubber Foot 4 OEOQO651A Washer 2.6 mm (plastics) 0E00713A Screw M3x6 Philips Truss Head 4

OE00593A Screw M3x6 Philips Binding 2

Head

3. LA-100 LINE AMPLIFIER

General

LA-100 is an amplifier with a flat frequency response that

may be inserted between amplifiers connected to input or

output of a tape deck or the like when the gain of the

amplifiers is insufficient.

The gain is selectable at four levels, 0, +6, +12, and +18

dB by combination of IN/OUT of two gain switches of 6

dB and 12 cB.

The voltage amplification of LA-100 at each status of the

switches is as follows:

S;: open, S,: close;

9.1k//27k Avi) = 6.8 k = 1 [0 dB]

S,: close, Sz: close;

_ 91kK//27k ,

Ava) =e gk/68k 7 2 1698!

S,: open, Sz: open;

_—(IM+9.1k)/ 27k | a) a“ Vom [12 dB]

S,: close, S.: open;

1M + 9.1 k) // 27 k Aya) — IM eS = 8 {18 dB]

6.8 k //6.8k

Schematic Diagram

L.A. P.C.B. an = ~

~ | Can

101,102 | C101 2SC1222 $e

CN-2 3.34 pals jy x2 rN

R17 9.1K{(G)

Ci07 410P

Specifications

Maximum Power Consumption...

Current Consumption ........

Total Harmonic Distortion .....

Frequency Response.........

Signal-to-Noise Ratio

Reference Level

Input Impedance ...........

Output Level/Output Impedance. .

Mute Function ............

Dimensions ..........++.25

WIGNT 2-6 bike ee 8 eee eee

System Diagram

Input

©

Q108 2SA733

C105 470u10V

27K(G)

1VA

50 mA

0.005% (20 Hz — 20 kHz,

1 V Output)

10 Hz — 75 kHz +0,

—0.5 dB

better than 100 dB (+ 18 dB

Gain)

Gain Switch O dB: 1V

6dB:0.5V

12 dB: 0.25 V

18 dB: 0.126 V

50 kQ

1 V/560 2

Furnished

7-1/2(W) x 2-3/8(H) x

4-1/16(D) inches

190(W) x 60(H) x 103(D) mm

2.7 |b, 1.2 kg

Out put

POWER QU TPUT

ral Om


Schematic Ref. No.

Q101,102

104,105

201,202

204,205

Q103,109

110,203

209,210

Q106,107

108,206

207,208

D101,102

103,104

105,201

202,203

204,205

R101,201

R102,202

R103 ,203

R104,115

204,215

R105,114

205,214

R106,107

206,207

R108,109

120,208

209,220

r

BA03859A

OBO7721A

OBO06062A

0B01872A

OBO06013A

OBO1909A

OB05700A

OBO5563A

OBO5608A

OBO5569A

OBO5559A

OBO05933A

OB05678A

Description

LA-100 P.C.B. Ass’y

LA P.C.B.

Transistor

Transistor

Transistor

Silicon Diode

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor 47

Carbon Resistor 680

Metal Film Resistor 6.8K

Carbon Resistor 560

Fig. 3.3

2SC1222 (2)

250945

2SA733

181555

ERD-14V J

ERD-14V J

ERD-14V J

ERD-14V J

ERD-14V J

ERO-25VK

G ERD-14V J

Schematic Ref. No.

R110,210

R111,211

R112,212

R113,213

R116,216

R117,217

R118,218

R119,219

R121,122

221,222

R123,223

R124 ,224

C101,201

C102,202

C103,203

C104,108

204,208

C105,106

205,206

C107 ,207

SWw1

CN1

CN2

0OB05661A

OBOS511A

OBO5663A

OBO5650A

OB05935A

OB05934A

OBO5564A

OBO5591A

OBO05567A

0B01920A

OB05562A

0B01863A

0B01404A

0B05744A

0B01412A

OB05884A

O0BO05798A

0B07170A

OBO08236A

0B08182A

Description

Carbon Resistor 22K

Carbon Resistor 820

Carbon Resistor 10

Carbon Resistor 12K

Metal Film Resistor 27K

Metal Film Resistor 9.1K

Carbon Resistor 1M

Carbon Resistor 15K

Carbon Resistor 33

Carbon Resistor 100K

Carbon Resistor 47K


3.3u


47

Ceramic Capacitor 33P


10u


470


Push Switch

4P-T Post

6P-T Post

ERD-14V J |

ERD-14V J

ERD-14V J

ERD-14V J

ERO-25VK

G

ERO-25VK

G

ERD-14V J

ERD-14V J

ERD-14V J

ERD-14V J

ERD-14V J

16V

6.3V

16V

10V

SUE22


LOT

0HO03518A

BA03859A

0J03654B

JA03061A

0J03440A

OB08290B

0J03277A

OBO8355A

OHO3519A

OH03437A

0£00713A

OEO0593A

LA-100 Mechanism

Upper Cover LA

LA-100 P.C.B. Ass’y

Front Chassis

Push Button Ass’y

Switch E Block Base

6P Pin Jack

Metal Seat Nut

4P DIN Socket

Main Chassis LA

Rubber Foot

Screw M3x6 Philips Truss Head


Head

Fig. 3.4

OE00157A

OEOO606A

0E00612A

OE00594A

0E00037A

0E00714A

OE00651A

OE00507A

Nh DB B — AQ AQ = o AQ ar ao an

10



(3A) Screw M3x6 Philips Pan Head

(2A)


Head

Earth Lug B-5


Head .

Washer 2.6 mm (plastics)

Nut Hex. M3

4. BA-150 BRIDGING ADAPTOR

General

Except for the exclusion of power supply from BA-150,

BA-150 is identical to the BA-100 presently available.

Connection of BA-150 across a preamplifier and stereo

power amplifiers allows the usage of stereo power ampli-

fiers in monaural use, and delivers the power amplifier

output twice the output in the stereophonic configuration.

The use of Nakamichi 420 or 620 power amplifier permits

the power output increase to 120W or 350W, respectively,

and thus the sound quality is expected to be improved.

Transistors Q101 and Q102 in the first stage constitute an

emitter follower and a constant current power supply

respectively. Q104 and Q105 constitute a differential

amplifier, and Q103 and D101 provide a current mirror

circuit. Q106 and Q107 constitute a phase inverter and

the output of Q107 is a phase-inverted signal of the input;

that is, this unit, receives an input signal and outputs it as

a non-inverted output and a phase-inverted output, and

permits bridging of the left and right outputs of the power

amplifiers to form a monaural power amplifier.

Schematic Diagram

B.A. P.C.B.

Q R101 C104 330 06910 16V

InpuT =§s QE % NSS mx +O oe awn fed

LEFT |

+O RED

Ox oO

R201 C201 INpuT (Q)EL

R203

RIGHT

RED R207 C202 +@ R216 6305

R208

Specifications

Maximum Power Consumption... 0.6 VA

Current Consumption ........ 25 mA

Reference Input Voltage ...... 1V

Input Impedance ........... 10 kQ

Reference Output Voltage ..... 1V

Output Impedance .......... 500 2

Maximum Input Voltage ...... 4V

Maximum Output Voltage ..... 4V

Maranarsiiee within 1° (5 Hz — 50 kHz) Phase-symmetry Degree

Dimensions .............4. 7-1/2(W) x 2-3/8(H) x

3-13/16(D) inches 190(W) x 60(H) x 97(D) mm

Went 6 6 ow Se pee Se a Se 2.4 lb, 1.1 kg

Non- inverted Output

Inverted Output

Q001 28C1222

aS C004 } 470u10V

@ T— xn

470, 10V )

7

470 10V

OUTPUT


Q001,101

102,104

105,201

202,204

205

Q002,103

106,107

203,206

207

D101,201

R001 ,002

105,205

201,213

R102,202

R103,203

R 104,204

R106,206

R107,116

207,216

R108,117

208,217

R109,115

209,215

R110,111

210,211

R112,212

R114,214

h Schematic

R101,113 |

BLU

RED

BLK

BAO3863A BA-150 P.C.B. Ass’y R118,119 | OBOSSE7A ial Resistor ERD-14V J |

218,219

0B07698B BA P.C.B. C003 ,004 OB05884A econ Capacitor

OBO6062A Transistor 28C1222 (2) 106,107 470u 10V

206,207

C101,201 0B01412A Electrolytic Capacitor

10u 16V

~C€102,105 | O0B01389A Electrolytic Capacitor

OBOGO13A Transistor 2SA733 202,205 4.7 16V

C103 ,203 0B01404A Electrolytic Capacitor

47y 6.3V

C104,204 | OBO05599A Ceramic Capacitor 150P 50V

OBO1909A Silicon Diode 181555 O0E00037A Earth Lug B-5 (1 pce.)

OBO5538A Carbon Resistor ERD-14V J 27K

0B01789A Carbon Resistor 330 ERD-14V J

OBO5665A Carbon Resistor 560K ERD-14V J



OB05558A Carbon Resistor 100 ERD-14V J

OB05678A Carbon Resistor 560 ERD-14V J

0B01920A Carbon Resistor 100K ERD-14V J

OBO05895A Metal Film Resistor 10K ERO-25VK

G 0B01782A Carbon Resistor 2.7K ERD-14V J

OBO5661A

0B01793A 22K

3.3K

Carbon Resistor

Carbon Resistor ERD-14V J

ERD-14V J

12


BA-150 Mechanism OE00037A Earth Lug B-5

OE00507A Nut Hex. M3

OE00594A Screw M3x8 Philips Binding

Head

OHO3523A Upper Cover BA-150

BAO3863A BA-150 P.C.B. Ass’y

0B08290B 6P Pin Jack

0JO3277A Metal Seat Nut

OBO8355A 4P DIN Socket

HA03709A Main Chassis BA Ass’y

0H03437A Rubber Foot

0E00713A Screw M3x6 Philips Truss Head

OEQO606A Screw M3x6 Philips Pan Head

(3A)

OE00157A Washer 3 mm (plastics)

0E00714A_ | Screw M2.6x6 Philips Binding Head

OEO0651A Washer 2.6 mm (plastics)

ha PR PND HH | =

13

5. MB-150 MC BOOSTER AMPLIFIER

General

MB-150 is a booster amplifier used to increase gain for an

MC type cartridge at low output level.

The gain can be selected at two levels of 38 dB/22 dB by

switching the Gain Switch ON/OFF. With the Pass Switch

set to ON, the input from the cartridge is directly deliv-

ered as the output without passing through the amplifier.

Complementary circuits used in all stages of MB-150 re-

duce distortion.

The first stage is composed of 10 PNP transistors and 10

NPN transistors, with low noise figures at small signal

source impedance, which are connected in parallel respec-

tively to ensure low noise figures.

The second stage adopts the particular triple transistor

configuration as used in the first stage of Nakamichi 610,

410, and 630 Equalizing Amplifiers, and its equivalent

input noise figure is less than —158 dB (with RIAA IHF-A

Network).

The first-stage transistors have the combination of NPN and PNP. Theoretically, if the characteristics of both types are the same, the collector currents of these transistors are equal, and their base currents are the same if the current amplification he _’s are equal; therefore d.c. voltage across the input terminals vanishes at the identical values of + and — power supply voltage. In actual circuits, However, a + or — voltage slightly remains due to various factors and the voltage should be adjusted to zero by offset voltage adjustment.

System Diagram

38qB~

22dBU Gain

Offset Voltage Adjustment

1. Insert shorted pin plugs into input jacks of MB-150,

2. Connect a PS-100 power supply unit to the MB-150

and turn the power switch of the PS-100 ON.

3. Connect an amplifier to the output jacks and listen

to sound with headphones or a speaker.

. Adjust semi-fixed volumes VR101 and VR201 so

that switching noises generated at the ON/OFF

operaton of the pass switch reduce to a inaudible

level.

Specifications Maximum Power Consumption... 2VA

Current Consumption ........ 100 mA

Total Harmonic Distortion ..... 0.005% (20 Hz — 20 kHz,

0.3 V Output)

Frequency Response......... 20 Hz — 100 kHz +0, —1 dB

(+ 38 dB Gain)

10 Hz — 100 kHz +0,

—0.5 dB (+ 22 dB Gain)

—158 dB (RIAA, IHF-A

Network)

Equivalent Input Noise

Ref. Output Level/Output

Impedance

Ref. Input Level/Input Impedance .

5 mV/5.6 Q

0.4 mV/56 Q (+ 22 dB Gain)

63 ywV/56 Q (+ 38 dB Gain)

200 mV (+ 22 dB Gain)

30 mV (+ 38 dB Gain)

Maximum Input Level

Dimensions .............. 7-1/2(W) x 2-3/8(H) x

3-15/16(D) inches

190(W) x 60(H) x 100(D) mm

WOIGNt: . atic ace = Exel Se SS 2.9 Ib, 1.3 kg

Fig. 5.1

14


Fig. 5.2

Schemati ipti ,

MB-150 Mechanism OE00593A Screw M3x6 Philips Binding

Head

Schematic Ref. No.

LO2 2

OHO3521A Upper Cover MB 1 OE00157A Washer 3 mm (plastics) BAO3860A MB-150 P.C.B. Ass’y 1 OEQO606A Screw M3x6 Philips Pan Head

0J03654B Front Chassis 1 (3A)

0J03440A Switch E Block Base 1 OE00612A Screw M3x6 Philips Pan Head

JAO3061A Push Button Ass’y 2 (2A)

0B03920B Ground Terminal 1 0E00732A Washer 3 mm

O0JO3277A Metal Seat Nut 2 OE00037A Earth Lug B-5

OBO8394A 6P Pin Jack 1 OE00507A Nut Hex. M3

OBO08355A 4P DIN Socket 2 OE00594A Screw M3x8 Philips Binding

OHO03522C Main Chassis MB 1 Head

OH03437A Rubber Foot 4 0E00714A Screw M2.6x6 Philips Binding

0E00713A Screw M3x6 Philips Truss 4 Head

Head OEO0651A Washer 2.6 mm (plastics)

15

Schematic Diagram

R103 820

eine REET, CN TS OE ES SS A LS a Mr

R121 33

3.3K Q10i—Q110 = 2SA991x10 3 ae a

ye HOE &

bs ds cs hs i is hs 2801844 x10

ca C110 Zé 470y10V

Q116—-Q125

R108 150

C212 R215 INPUT

Arh aAarAAAe

i is Gf sa RIGHT

OUTPUT


K gy oe aan #% os &

“oe £ & Bex Su &

OUTPUT

(TR P.C.B.) 28C 1844 x5

Q121_ Q122 Q123 Q124 Q125

Q221 Q222 0223 0224 Q225

Q106 Q107 gios Q109 Qno

Q206 Q207 Q208 Q209 Q210 2SA991 x5

Fig 5.5

0101-113

201-213

Q114,214

0115,215

Q116-128

216-228

Q129,229

VR101,201

R101,201 R102,202 R103,104 203,204

R105,106 205,206

R107,108 207,208

R109,110 209,210

R111,112 211,212

R113,213 R114,214 R115,215 R116,216 R117,217

R118,218 R119,219 R120,220 R121,122 221,222

R123,124 223,224

C101,201 C102,103 202,203

C104,105 106,107 110,111 113,114 204,205 206,207 210,211 213,214

C108,109 208,209

C112,212 SW1 CN1

0B07722A

0B06120A

OBO6062A

0B01872A

0B06119A

OBO6121A

0B07159A

OB05587A

0B01885A

OBO5511A

0B01793A

OBO05649A

OBO5558A

OBO5545A

OBO5661A

0B01879A

OB05818A

OBO05562A

OBO05952A

OB05746A

OB05854A

0B01920A

OBO5567A

0B01833A

OB01914A

OB01289A

OB05884A

0B01288A

0B01290A

0B07167A

0B08236A

OBO8366A

0B07738A

Schematic —

BAO3860A MB-150 P.C.B. Ass’y

MB P.C.B.

Transistor

Transistor

Transistor

Transistor

Transistor

Semi-fixed Volume

Carbon Resistor

Carbon Resistor |

Carbon Resistor

Carbon Resistor

Carbon Resistor |

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor .

Carbon Resistor

Metal Film Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Carbon Resistor

Mylar Capacitor

Ceramic Capacitor

2SA991 (26 pes.)

28C1222 (2)

280945

25C1844 (26pcs.)

2SA990

500

56 ERD-25V J

39K ERD-25V J

820 ERD-25V J

3.3K ERD-25V J

150 ERD-25V J

100 ERD-25V J

18 ERD-25V J

22K ERD-25V J

33K ERD-25V J

5.6 ERD-25V J

47K ERD-25V J

91 ERO-25VK F

1 ERD-25V J

6.8 ERD-25V J

100K ERD-25V J

33 ERD-25V J

10K ERD-25V J

3300P 50V

220P 50V


470u 10V

Ceramic Capacitor

100P 50V

Ceramic Capacitor 0.01u 50V

Push Switch SVE

4P-T Post

Shield Case MB (2 pcs.)

TR P.C.B. (2 pcs.)

6. EC-100 ELECTRONIC CROSSOVER

General

EC-100, a combination of a high-pass filter, a phase shifter

and an adder, separates an input signal into a high-passed

output and a low-passed output.

Each of the two output signals is delivered to a respective

power amplifier for driving a 2-way speaker system.

A combination of two or more EC-100’s makes it possible

to drive. a 3-way or 4-way speaker system.

The transfer function Gy(s) of a high pass filter is given

by the formula:

Gy (s) =

as.

The transfer function of Eq. 3 accords with that of a low

pass filter circuit. Therefore the output of the adder is a

signal of lower frequency range.

The crossover frequency setting of EC-100 at 19 steps

from 66 Hz to 7.4 kHz is possible by adjusting the

Frequency Control VROO1.

The Frequency Control is interlocked at 19 frequency

positions in total, including 10 positions marked on the

Frequency Control and 9 positions at the middle of them.

These frequencies are 66, 68, 78, 95, 120, 170, 250, 320,

370, 440, 530, 660, and 880 Hz and 1.4 k, 2.4 k, 3.9 k,

5.4 k, 7 k, and 7.4 kHz. The attenuation characteristic of

the filters is 12 dB/oct.

EC-100 has the same characteristics as conventional multi-

band filter circuits; however, in the crossover frequency

switching system of EC-100 is improved from conventio-

nal systems that have to change the resistance and capaci-

tance simultaneously to the system changing only the

resistance.

Note:

Specifications Maximum Power Consumption .. .

Current Consumption

Attenuation

es ses e© # 8s 8 « ©

es 8s e @ 8 8&s © 8 8 8 #@ 8 8 6

Distortion

Signal-to-Noise Ratio ........

Ref. Input Level/Input Impedance .

Ref. Output Level/Output

Impedance ..........0004

Maximum Input Level

Mute Function

Dimensions

Weight

System Diagram 2VA

100 mA

12 dB/oct.

66, 68, 78,95, 120, 170, Input

Cc > 250, 320, 370, 440, 530,

660, 880 Hz, 1.4 k, 2.4 k,

3.9 k, 5.4 k, 7 k, 7.4 kHz

less than 0.005% (20 Hz —

20 kHz)

better than 110 dB (IHF-A

Network)

1 V/50 kQ

1 V/560 2

4V

Furnished

7-1/2(W) x 2-3/8(H) x

3-15/16(D) inches

190(W) x 60(H) x 100(D)mm

2.4 Ib, 1.1 kg

Schematic Diagram

Resistors and capacitors marked with * will be adjusted in order to achieve

accurate crossover frequencies when frequency volume is interlocked at 19

positions.

The standard value of these resistors and capacitors are shown in the figure.

| 2SC900x3

cio CN-3 ton 46V

VROO1 200KC Frequency

_—— a ce ee ee ee a

‘\

C204

eee wie |

(9) N °o or

| | |

ee ee oe ae ee oie a | High Pass Filter |

a4 | 23 | 2s! Ph | ase Shifter

S| Se a a

* awd? es | : ! | z ! | | | | | | | ii ! (es cette eae ee en atest 3]

R110 1.8K

cr C104 | | C105 O.012u} | 0.042u 3

| IC

R2t2

C107 10u 16V 10

co)

R210

oo)

R2i5 w ec

C207

17

High Level

High

Volume ©) High Pass Out put

——— — ie)

| SS

| e | Mute

Low

| volume 7) Low Pass | Out put

| 06 | NaN

fons <a oc

Mute

GND (1)

iia BE: dl R301 Or

19 POWER OUTPUT

R123 excel

yd (4 WHT ©) Leh

i High Pass Output

1$1555 (2) ©) Sel

Q105 2sc945 eane

iy CN-2 YEL N (3) é ) as N

J CH Low Pass Output

josceas 4 O10, (a) 8LY__) ren 4 )) Rech

Low Level


© D203. R213 47K

Schematic Ref. No.

1C001,101

201

0101,102

103,201

‘202,203

0Q104,204

0.105,106

205,206

D101,102

103,201

202,203

VROO1

VRO002,003

R101,201

R102,202

R103 ,203

R104,204

R105,205

R106,206

R107,117

121,207

217,221

R108,109

208 ,209

301,302

R110,112

210,212

R111,113

211,213

Part No.

BA03868A

0B07739B

0B06124A

|0B01910A

OBO6066A

0B01872A

0B01909A

0B07182A

OB07181A

O0B05700A

0B01564A

OBO5608A

OBO05593A

OBO5606A

OB05688A

0B01833A

OBO5663A

0B01830A

OB05641A

Description

EC-100 P.C.B. Ass’y

EC P.C.B.

IC 4558

Transistor 2SC900 (E)

Transistor 2SD471

Transistor 2SC945

Silicon Diode 181555

Volume 200K (C)

Volume 10K (B)

Carbon Resistor 470K ERD-25V J


Carbon Resistor 220 ERD-25V J






Carbon Resistor 1.8K ERD-25V J


Schematic Ref. No.

R114,115

118,119

214,215

218,219

R116,120

122,216

220,222

R123,124

223,224

C101,107

201,207

C102,103

202,203

301 302

C104,105

204,205

C106,206

C108,208

C109,209

CN1,2,3

18

Part No.

OBO5955A

OBO5566A

OB05678A

0B01412A

OB05884A

OB05843A

OB05681A

0B01862A

0B01913A

OB08236A.

Description

Metal Film Resistor 1OK

Carbon Resistor 2.2K

Carbon Resistor 560.


1Ou


470u

Mylar Capacitor 0.012yu

Mylar Capacitor 0.01y


22u

Mylar Capacitor 1800P

4P-T Post

ERO-25VK

D

ERD-25V J

ERD-25V J

16V

10V

16V

0HO3528A HA03714A BAO3868A 0J03689B 0B08290B 0J03277A OBO8355A HA03713A 0HO3437A 0E00713A


LO2 Fig. 6.4

EC-100 Mechanism

Upper Cover EC

VR Knob Ass’y

EC-100 P.C.B. Ass’y

VR Holder MX

6P Pin Jack

Metal Seat Nut

4P DIN Socket

Main Chassis EC Ass’y

Rubber Foot |

Screw M3x6 Philips Truss Head Dm PB - AQ A) a a 2 GW w=

19

OE00593A

0£00157A

OEOO606A

0E00507A

0E00037A

OE00594A

0E00714A

OE00651A


Head



(3A)

Nut Hex. M3

Earth Lug B-5


Head


Head


7. MX-100 MICROPHONE MIXER

General

MX-100 is a mixing unit having three microphone inputs

for L-channel, R-channel, and Blend. In addition to the

use as a simple microphone mixer connected to line input

terminals on a tape deck, the unit allows the application

to a PA (public address) amplifier directly connected to

an Aux. input of a preamplifier, etc.

Further, connection of this unit to Nakamichi 600 (a

cassette console) makes microphone recording by Naka-

michi 600 possible.

In addition, connection to the line input of a cassette

system, such as Nakamichi 7O00I!, 10001! or 500, allows

recording using six microphones. |

In Fig.7.1, the gain of the -channel microphone amplifier

is given by the formula:

es RV1 Av(L) R, + Rx, + RY oa ere 1

and the gain of blend microphone amplifier:

RY2 9

Av(B) “Ry + Rxp + RY” Swaine eee teh Ok Beate

The gains of the mixing amplifier:

il Av(ML)

Av(MB)

R</R3 (for L-channel mic. amp. output),

R./Ra (for Blend mic. amp. output).

System Diagram

Left \

R4

Blend

Blend Mic. R2 Volume

Riglt

Therefore the output of the L-channel is expressed as:

Rs R Av(LO) = Av(L)—= + Av(B)—>~

R3 Ra

Similar to the L-channel, the signal of blend microphone

is mixed in the R-channel.

Specifications

Maximum Power Consumption. . . 1VA

Current Consumption .....-+-- 50 mA

Total Harmonic Distortion ..... 0.05% (10 kHz, 1 V Output,

1 V Input)

Input Sensitivity ... 6... +++: 0.2 mV

Input Impedance ....-- +++: 10 kQ

Output Level/Output Impedance. . 100 mV/560 2

Maximum Input Level ......--- 1V (+ 74 dB)

Mute Function .....---+e+:5 Furnished

Dimensions .....--++e eee 7-1/2(W) x 3-3/8(H) x

4-5/16(D) inches

190(W) x 6O(H) x 110(D)mm

Weight... 6-00 ee ee es 2.7 |b, 1.2 kg

L Channel ©) Output

“6 LA

Mute

R Channel ©) Output

ae) LA,

Mute

Fig. 7.1

Schematic Diagram

MX. P.C.B.

| ty On re

C104 1580v oe | MIC. Ri02 | x Leh 100 9 ~N ae ae =o 2SA7T33

BLK & Q104 1a

2sc1222 NUN oF : YEL o OUTPUT

wo

on Q106 700 Vv = 28C945 be

R15 &

a -.

40K(G)

BLU

MIC.

Rech

0.2mvV

BLK OUTPUT UO Rech

100mV

- DIN JACK

BLEND MIC 6

0.2mV 8 Q303 % 280945

BLK cN-1 Oo

Ez i OUTPUT

Fig. 7.2

21


Schematic eae Schematic dads

BAO3866A

Q101,104

201,204

1 301

0102,105

202,205

302

Q103,106

107,203

206,207

303

D101,102

201,202

VR101,201

301

R101,201

301

R102,123

124,202

223,224

302

R103,203

303

R104 ,204

304

R105,205

305

R106,206

306

R107,207

307

R108,208

308

0B07724A

OBO6062A

OBO6013A

0B01872A

0B01909A

0B07175A

OBO5563A

OBO5558A

OBO5591A

OBO01564A

OB05847A

0B01878A

OBO5669A

OBO5661A

MX-100 P.C.B. Ass’y

MX P.C.B.

Transistor 2SC1222 (2)

Transistor 2SA733

Transistor 2SC945

Silicon Diode 181555

Volume 10K (C)





Metal Film Resistor 51 ERO-25VK

F

Carbon Resistor 8.2K ERD-14V J



R109,209 | 0B01792A 309

R110,120 | OBOS562A 122,126 210,220 222.226 310 |

R111,211 | OBO01795A 311,312

R112,212 | OBO5673A R113,114 | OBOS645A 213,214 313,314

R115,116 | OBO5895A 215,216 |

R117,217 | OBOS650A R118,218 | OBO5538A R119,219 | 0B01789A R121,221 | 0B01793A R125,225 | OBO5678A C101,104 | 0B01412A 107,108 201,204 207,208 301,304

C102,202 | 0B01288A 302

C103,203 | 0B01394A 303

C105,106 | OBO5885A 205,206 305,306

C109,110 | OBO5841A 209,210

CN1 OB08236A

22

n

Carbon Resistor 470

Carbon Resistor 47K



Carbon Resistor 270

Metal Film Resistor 10K

Carbon Resistor 12K

Carbon Resistor 27K

Carbon Resistor 330


Carbon Resistor 560


10u



220u


100u


330u

4P-T Post

ERD-14V J

ERD-14V J

ERD-14V J

ERD-14V J

ERD-14T J

ERO-25VK

G

ERD-14V J

ERD-14V J

ERD-14V J

ERD-14V J

ERD-14V J

16V

6.3V

10V

10V

Schematic Rcd 7 Schematic

LO2

OHO3526A

HA03714A

BAO03866A

0J03689B

0B03882A

OB08362A

OB08355A

HA03711A

0H03437A

0E00713A


MX-100 Mechanism

Upper Cover MX

VR Knob Ass’y

MX-100 P.C.B. Ass’y

VR Holder MX

Headphone Jack

2P Pin Jack

4P DIN Socket

Main Chassis MX Ass‘y

Rubber Foot

Screw M3x6 Philips Truss

Head

Fig. 7.4

fA ND ]H WHS | WO

LO3

LO4

LO5

LO6

LO7

OE00593A

O0E00157A

OEOQO606A

OE00766A

O£00714A

OEO0651A

2 Screw M3x6 Philips Binding

Head



(3A) Screw M3x8 Philips Binding

Head TP


Head


Manual: EC100 SM NAKAMICHI EN - archive.org

Documents