Nakamichi T-100 User manual

NAKA-00088
Service Manual
Nakamichi
Nakamichi
T-100
Audio Analyzer

CONTENTS
1.
2.
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VW.
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Wo 1, Control Functions ........ 2
Va. :2, Voltage Selector.......... 3
1, 3. Functions ..........-.-5 3
1. 4, How To Read Signals 5
1.°¢5. Semiconductor Switch 5
Removal Procedures .. 1.2200. eee ee cee reer cece eee eee ee eee tee tent eee e renee 6
2. 12 Top Cover Ass’y, Bottom Cover Ass’y and Synthesis Mechanism Ass’y with Power Supply Ass’y... 6
2. 2. Power SUPPIV ASS Vi? 5.22850 hissed LORS hs ad tate See teig oe Wit eset Ss ent Eee Bee Be dk ede 7
2 3. Connector P.C.B. Ass’y «0. ee ee eee eee 7
2. 4. Switch Control Ass’y and Bar-graph Holder Ass’y . . 7
2. 5. GP Pin Jack Ass’y 2... eee cee eee 7
2 6. Switch P.C.B. Ass’y and Votume P.C.B. Ass'y 2... cee cee ee ete eee en neee 8
2 7. Display P.C.B. Ass’y and Bar-graph 2... ce cee eee ett eee et neee 9
2 8, Power Supply P.C.B. Ass‘y and Power Transformer . 10
2 9. Rear Panel A Ass'y, Power Switch and AC Inlet... 10
Measurement Instruments .. 20... 0000 v eee eee e renee 10
Parts Location for Electrical Adjustment............... 11
44, CUrrent TY Pe accede ee See eee ee ea 1
4. 2, Previous Type ........ 2. eee eee eee eens 11
Adjustment and Measurement Instructions ..........-..,0000- staat 12
5. 1. Current Type.............08 See ODE ae tein & foe Sab Sande diby skater ere iececaueuhw sara rapsress abate cates 12
5, 2, Previous Type»... eee ee eee eee eee 15
Mounting Diagrams, Circuit Diagrams and Parts List 18
6. 1 IC Block Diagrams 18
6 2 Connector P.C.B. Ass’y 19
6 3. Power Supply P.C.B. Ass’y 21
6 4, Wow & Flutter P.C.B. Ass’y .. 23
6, 5, Switch P.CB.Ass’y.. ce eee cette ee ete nent cette emcee tense tee tn nee 25
6. 6 Oscillator 'P.C:B.:Ass’yoss.i.3 eccd ioe de ey eee bie ea ene eee ee ne 25
6. 7. Absolute Rectifier P.C.B. Ass’y .. 2.22.20 0.05 : esa eh
6. 8 Linear/Log. Converter P.C.B. Ass’y Bila ghd 29
6 9. Distortion P.C.B. Ass’y 1... eee eee eee Setiexionpe: 2Ot
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6. 11. IHF-A WTD Network P.C.B. Assy 35
€ 12. Display P.C.B, Ass’y 37
6 13. Analog Multiplier P.C.B. Ass’y 39
Mechanism Ass’y and Parts List... 2.2... 0. cece eee eee ee eee eee 41
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7. 2. Synthesis Mechanism Ass’'y {(AO1) 2... ce ce eee eee eee nee eee 42
7 3. Power Supply Ass‘y (A02) 43
7 4. Switch Control Ass’y (B01) 45
7 5. Bar-graph Holder:Ass’y: (BOQ)? seg 2-5, e-v ecesce womeeees dasha veteraereeraye re wos oe tebe validy dae Ae 46
7. 6. Connector Ass’y (B03) 47
Block Diagram ......., 48
Wiring Diagram ........ 49
Troubleshooting: ca teen he ie a eye eee ee Baik ea ce aresw ddd eased da febalra te 1a Ja Ranaehareialayalniinadereoe end ae lo 50
10. 1. Notes 50
10. 2. Troubleshooting . 50
Specifications 53

1. GENERAL
1.1, Control Functions
The Nakamichi T-100 control functions are shown below:
Peapennpriny
2 2 4
h Audio Analyzer T-100
Fig. 1.1 Front View
———— PLB. Assembly
Audio Analyzer T100
vel somone ! 4 i
Powar Consurmtion —1BVA W
ating Curt 190mA
1. Osellator 3. Wow/Flutter 8. Abs, Rovtitior 2. Log
2 WId-A Network — 4, Oistnrtion, 6. Ansley, Muttote: Converter
Mai in daoen
Fig. 1.2 Rear View
. Speed Deviation Scale
. Top Indicator
Level Scale
Bottom Indicator
Total Harmonic Distortion/
Wow & Flutter Scale
Speed Calibration Control
. Function Control
. Meter Range Switch
. Input Level Switch
10. Input Level Controls
11. Oscillator Control
12, Oscillator Output Control
13, Fuse Fig. 1.3 Side View (Right) Fig. 1.4 Side View (Left)
14, Power Switch
15. AC Cord Connector
16. Input Jacks
17. Oscillator Output Jacks
18. Scope Output Jacks
GQakONS
on
Inport fev ioiths Scope’
PS
-€
oO

1.2. Voltage Selector
Voltage selector is installed on the rear panel for Other
Version of the Nakamichi T-100.
This voltage selector can select either 120 V or 220 - 240
V at customer's disposal.
1.3. Functions
T-100 contains 9 functions the details of which are as
follows:
Figs. 1.5 - 1.13 show the signal path in each function.
(1) Speed Cal
Calibrates top indicator for zero speed deviation.
(2) Speed Unweighted
Selects speed deviation in the top indicator and unweight-
ed wow & flutter peak on the bottom indicator.
(3) Speed Wow/Fiutter
Selects speed deviation on the top indicator and weighted
wow & flutter peak on the bottom indicator.
{4) Level T.H. Distortion L
Selects left channel level on the top indicator and left
channel total harmonic distortion on the bottom indica-
tor,
SPEED CAL.
{5) Level T.H. Distortion R
Selects right channel Jevel on the top indicator and right
channel total harmonic distortion on the bottom indica-
tor.
(6) Level
Selects left channel level on the top indicator and right
channel level on the bottom indicator.
(7) Level —20 dB
Decreases oscillator output by 20 dB while simultaneously
making the indicators 20 dB more sensitive.
Selects left channel level on the top indicator and right
channel level on the bottom indicator.
(8) Noise -40 dB
Displays teft channel A-weighted noise on the top indica-
tor and right channel A-weighted noise on the bottom
indicator.
Makes the display 40 dB more sensitive.
Seope
woot = oT
Display
Speed
Pink }[_Sin_][nHz
Unweighted
Display
Speed
Weighted

{9) Peak
Selects peak-reading ballistics for the level display. Selects
left channel level on the top indicator, right channel level
on the bottom indicator. When the left and right input
level controls are turned to maximum, the sensitivity of
LEVEL T.H. DIST. L
Scope
Input ~ Lom
Input ~ RO
Ose
Outpur
the disptay is the same as when the function control is
set to “level”.
However, by turning the input level controls counter-
clockwise, you can reduce the sensitivity to any inter-
mediate value.
Distortion (L)
RH
Osc. 400 Hz eT
LEVEL T.H.DIST. &
Display
Level (R)
Distortion (R)
Input = Lo
Input = R
Scope
Input -L om
Input = R
{__ Display "J
Noise Level (L)
A =40 4B
Peak Level (L)
Ore
Output
Bink [Sin] [axes Speed
Ose
Fig. 1.12
PEAK LEVEL
Seape
lapu = ©
Input -
ee
Satpun
>
Peak Levet (R)
‘Speed

1.4. How To Read Signals
In the Switch P.C.B. circuit, preceding 9 functions are
symbolized as follows:
A: Speed Cat.
B: Speed Unweighted
C: Speed Wow/Flutter (DIN WTD)
OD: Level T.H. Dist. (400 Hz) L
E: Level T.H. Dist. (400 Hz) R
F: Level 0 dB
G: Level —20 dB
H: Noise IHF-A (—40 dB)
|: Peak Level
Functions A to | are combined and described logically
such as A+B+C, A+B +C, etc. The meaning of these
signals are:
A+B+C: will be “H” (i.e., will be effective) if
function A OR B OR C is selected.
A+B+C: will be “L” (ie., will be effective) if
function A OR B OR C is selected.
Notes: 1. If the function other than A, B, or C is select-
: ed, signals A + B + C and A + B + C become
open in the Switch P.C.B. circuit, but in the
next stage —10 V or +10 V bias is applied to
signal A + B + C or A+B +C. Thus, the “L”
or “H” level is obtained.
2. “H" and “L™ levels should be as follows:
“H": +6.5V—+10V
“LY: -10 V -—-7.5V
Fig. 1.14 shows the actual circuit.
Common terminal of the Function Switch is connected
to +10 V or —10 V and terminals A, B and C become
inputs of DIODE OR Gate.
1.5. Semiconductor Switch
Circuits are controlled by the semiconductor switch of
FET and transistor. Below shown is the table for the
semiconductor switch and equivalent mechanical switch.
c
yi
78
+10V
4
cad
Satie deat d
7
On
o%
Peeee a,
B
Xa ® coo
560
~10v = EO
\ Fo
§ %
Function Switch
—[S—
O A+Bt+C
Fig, 1.14
Table 1.1
Circuit
Mechanical
Switch
Control
Input
FET
Control fnput
|
Input Output High ON
(+10v) | eo
—
OFF
Low seg
{-10V)
Transistor
L Contro{ Input
{nput | ON
High
(+10V) eee 0
OFF
Low
(-10V) ae

2. REMOVAL PROCEDURES
2.1. Top Cover Ass’y, Bottom Cover Ass‘y and Synthesis
Mechanism Ass’y with Power Supply Ass’y
Refer to Fig. 2.1.
{1) Remove F01, F02 and FO3, then disassemble FO4
(Top Cover Ass’y) and F05 (Acrylic Cover).
(2) Remove FO6 and FO7, then disassemble F08 (Bottom
Cover Ass’y) and FO9 (Synthesis Mechanism Ass’y
with Power Supply Ass’y).

2.2. Power Supply Ass’y
Refer to Fig. 2.2.
(1)
(2)
(3)
Refer to Fig. 2.1. Remove Top Cover Ass’y and
Bottom Cover Ass‘y referring to item 2.1.
Remove F01, then disassemble FO2 (Power Supply
Box Cover).
Remove FO3, F04 and FO5, then disassemble FO6
(Power Supply Ass’y).
2.3. Connector P.C,B. Ass’y
Refer to Fig. 2.2.
(1)
(2)
(3)
Refer to Fig. 2.1. Remove Top Cover Ass’y and
Bottom Cover Ass’y referring to item 2.1,
Remove FO5 and FO7, then disassemble FO8 (Rear
Panel B Ass’y).
Remove FO9, then disassemble F10 (Connector P.C.B.
Ass’y).
F18
2.4.
Switch Control Ass’y and Bar-graph Holder Assy
Refer to Fig. 2.2.
(1)
(2)
(3)
Refer to Fig. 2.1. Remove Top Cover Ass'y and
Bottom Cover Ass‘y referring to item 2.1.
Remove F11, then disassemble F12 (Switch Control
Ass’y).
Remove F13, then disassemble F14 (Bar-graph
Holder Ass’y).
2.5. 6P Pin Jack Ass’y
Refer to Fig. 2.2.
{1}
(2)
Remove F10 (Connector P.C.B. Ass‘y) referring to
item 2.3.
Remove F15, then disassemble F16 (Shield Plate),
F17 (6P Pin Jack Ass’y} and F18 {Pin Jack Name
Plate).

2.6. Switch P.C.B, Ass’y and Volume P.C.B. Ass’y {5) Remove F08, then disassemble FO9 (Switch P.C.B.
Refer to Fig. 2.3. insulator), F10 (Wire Holder 583) and F11 (Switch
(1) Refer to Fig, 2.2. Remove Switch Control Ass’y P.C.B, Holder Ass’y).
referring to item 2.4. (6) Remove F12 and F13, then disassemble F14 (Switch
(2) Remove FO1, then disassemble FO2 (Rotary Switch P.C.B. Ass’y).
Knob Ass’y). {7) Remove F15, then disassemble F16 (Volume P.C.B.
(3) Pull out FO3 (Slide Switch Knob) and FOQ4 (Cali- Ass’y) and F17 (Switch Holder).
bration Knob).
Remove FO5, then disassemble FOG (Front Panel
Ass'y) and F07 (Front Panel Stud).
{4
Fig, 2.3

2.7. Display P.C.B. Ass‘y and Bar-graph
Refer to Fig, 2.4.
{1) Refer to Fig. 2.2. Remove Bar-graph Holder Ass’y
referring to item 2.4,
(2) Remove FO1, then disassemble FO2 (Shield Cover
Ass‘y}
{3) Remove FO3, then disassemble FO4 (Display P.C.B.
Ass’y) and F05 (Display P.C.B. Insulator).
(4) Remove FO6, then disassemble FO7 (Scale Panel
Ass’y).
{5} Remove FO8, then disassemble FO9 (8P Plug P.C.B.
Ass’y).
(6) Remove F10 and F11 (Pressure Plate Ass’y), then
disassemble F12 (Bar-graph) and F13 (Bar-graph
Holder Ass’y).
Fig. 2.4