Nakamichi BX-300 User manual

Nakamichi
Service Manual
Nakamichi
BX-300
BX-S3O00E
Discrete Head Cassette Deck

CONTENTS
2.
3.
10.
11.
12.
Goeme rll, 55.5.5 e cree tae Se I foe NS We ce SS Goes Bie We eS Sele Sen late BS Bik: 8 eo br ede aed 2
Test Tapes and Gauges: es. oic8 sie les sits a paced who Ta 0 a as Biles oe bE Bile eed Ow) and a dle ae ik OG ate BE Bk Sao aM 2
Mechanical Adjustment’ .....6. 5.46068 ee 68 be 8 8 ee Sete © Rees a Beer a Da deane eG Bere eee hae 3
3. #1. Record Head and Playback Head Tilt Adjustment ...........0. 0... cc eevee eee ene eene 3
3. 2 Head: Base:Stroke: Cheek: $0537.66 20 asad & Sacto Ghd bat See ew ata BS She Bata? Np eed Ec gal bel bo 3
3. 3 Erase Head Stroke Adjustment and Tape Guide Height Check ...................200c0ee 3
3. 4 Erase Head Height and Tilt Adjustment ........ 0.00... cece eee ee ee eee eee eee 4
3. 5 Playback Head and Record Head Height Adjustment and Azimuth Alignment ............... 4
3. 6 Pressure Adjustment of Take-up Pressure Roller... 0.0... 0.0.0.0 ccc eee ec eee eeeeenes 5
3. #7 Tape-Travelling Check. s..5 6 c.556 cs aie ee Goa 6 Serene 4 We lg hehe Bes Mel a, HSE a) Siw Be Sata SEL 5
3. 8 Eject Damper Adjustment ........... cc eee ee eee ee eee ee eee eee eet eee 5
3. 9 Reel Motor Speed Adjustment in Play Mode ............ 0... ccc ee tee cee ee ee eae 5
3. 10. Tape Speed Adjustment ..2 6 io5.12.. ioe ee is Se he veces Sata BE Aw boo BRIE Soe le bw Dd Wer bebe ees 5
3. 11. Mitt Drica tion o.5 se. eh eh ee ele aoe aig Bae eRe Sasa Narre a hn de Dee Ode cba Rs BE Bae a 5
Parts Location for Electrical Adjustment... 2... .. 00.00. cee ee eee ee tee twee eee aes 6
Electrical Adjustments... o5:605. 6.606 bse eee bio ene 88, ER Se ww UAE Law! Ow A eee wee Bile Sig ee Gus ewe ew a 7
5. 1. Adjustment Instructions .. 0.0.2... 0... ccc ee eee eee eee ee eee eee wees 7
5. 2. Playback Frequency Response ......... 0... cc cece eee ce eee eee ee tee eee tee e ens 9
Mechanism Ass’y and Parts List... 2... ee ee tee eee te eee eee e nett e ee aee 10
6. 1. Synthesis: <seSsrah piece Samad wine eee seed ae: die na arc hat BP tec ibxk bite, aR Hn ah Pie oa eR tie gee 10
6. 2. Front:Panel; Ass’y (AOL). esos oo 68 06 oe Bi wie ee bee Sa) WOE Cea eae ere ene wa ae MS RS wees 11
6. 3. Synthesis Mechanism Ass’y (A02) .. 0... cc ee ee eee tw ee eee eee eee ene 11
6. 4. Front: Chassis Ass’y:(BO1)..6 go ei6. bn Poe Secs d Ww SOE ee nk, Ea a ee ae So De 12
6. 5. Cover: Plate Ass’y (BOQ): (ois ic hccono oes hiaiar Gea aeS ele Pe Se aust Sw) bs, ig Bw Ss 0d a ay bod fend wives Boece 13
6. 6. Mechanism: Ass’¥ (BOS). 5.5 o..scsyrsicarce ed ee 4 co oe a Ra Ow RH ISIWY Hew wile oh Gor NESS Ves wn we gael ioled ve 14
6. 7. Rear'PanelAss’y (B04) cc ccc 6 ee eee die 8 we wh See OE Ne ee WO ele ew See So Oe aw 15
Mounting Diagrams and Parts List .. 2... 1. ee ete ee ee ete ee tenet e ete e ees 15
7 1. Power Switch P.C.B: Ass’ 63 6 ésec5: oe lie be a a as BEN ale. rd, IS iw Wels LTR Se ee See erate 15
7 2. Shut-off:P:C:BcAss' yo o5o sch Relea BA Nen ok obra WOR RUS EE ibe alae ORL ala Slee ace be eee 15
7. 3. Fuse: P:C:B: Assy c5 2.5 op co S conte at, epee ew 5b, FG e BARI bo wi ew ol lon aH la vaso ates Heats a EOI 16
7. 4. Volume'P.C.B: Ase’ y <4 secen3 seis a toss eta See OS be a tigs atte leas Bea ee ca te ia ara ty BOR Gabe teaarer ed ae 16
7. 65. Input:Amp: P:C{B. Ass?y sesso cece oe See wn ek earns, Sut S, Wig foi Boe BS RE wee ee ee meena le Stennis 17
7. 6. Meter Amp.-P:C:BiAss’Y 66054 52h b Sie 0k hale eRe Beg e Oa Na OR Be bl esate ena ORS RIAA ES 17
7. 7%, Dolby NR: Switch: P:C.B: Assy. ie oi6: 6 see ieee ewok ae ohn Bik 0 Uae Rg ee Ta a aes er EN ah bok 17
7. 8. Control Switch P.C-B: Assy 3265 ssc2 3, ce, 6s ea sw Oe, ben Wine. BAS wR RAG SUR re BS BS RG 18
7. 9. Counter PCB. Assy sii diss. os; 5) 200 ose enh ose Se ren 0 ese Oo Benw wren aie Ooa Sea 6 OMe Wiles a back wd eT Kae 18
7. 10. Tape Switch:P:C. Bi Assy 232 sicsse 5.6 aire a ee Se oie ae. Hal TOS. dee ele goa fever Bo 8 a wea glare 18
7. 11. Main PC BAgs ty tock eee a5 aid beak ee oe lara s ee ee Sa EG See WED ae WR ed ORS. CUS patente 19
Schematic Diagrams .......... MM eae Naser Shenae Si rbica Welw ere maiielalcaladhce tenis. varvesien dcectel wicyloue folie erie ateiie ie) ar aneree an 23
8. 1. IC: Block: Diagrams <2 6266610 ies Ps sie Wak! oa hans Ss a ee gh Be. Gdal eRe Blea COG ahs, Gidea ware 23
8. 2. Schematic: Diagrams: > 535.5 d0.l5 ae ch aco: Siew ae Ceara word Blea dane Wa Ss See we ward ate, bw eles 24
Timing Chart and Eq. Amp. Frequency Response .......... 0.0 cece eee eee ewe tenet eee ee eeee 26
9. 1. Timing: Chart: io. ooo ood Giese aie bi wine: GR Se aA Baal hin Oey ol wid, tae eb ok eS OSE et Alas bad A ee ea 26
9. 2, Eq. Amp. Frequency Response .. 1.0.0.2... 0c cece ee eee eee eee eee teen e eee eee 26
Wiring: Diagram isis i ison 5 8 Sie cn bb ass ews ls cat aa as ira 9ve a tach ot ply SOTO ebay WSL OE Ga @ aa ahi elias 27
Bl OG; Dia eras: «55. ieee. so Seco ig.r8 gb! oS. A/G AS 9 col 6a eRe SSS gs we Sd Riad Wha ao, Ovorar ks 1aw, BNO led Mea a gee dees 28
11, #1. Amplifier:Seetionn i535.) es ecesaces gs eerie: seesaw. ak ap afer bh ab a Shag, cede Eira at Talvasv, Sa be) ei aca lep glen Sow facsds aie e 28
11. 2. Mechanism Control Section ....... 0... . ee ee ee tee et ete ee eee eee eens 29
Specifications ics: Ses eh hy, 58 as Fe te. Sy BS SEE SE Cia Rory wha ea) 8 lg: Meal Geer os ad “ah dca acaners 30

1. GENERAL
1.1, Voltage Selector
Voltage selector is installed on the rear panel for Other version of the Nakamichi BX-300.
This voltage selector can select either 120 V or 220—240 V at customer’s disposal.
1.2. Packing Materials and Owner’s Manual
Part No. Description
OF03812A Carton Box BX-300 (U.S.A., Canada, Australia & Others)
OFO03821A Carton Box BX-300 (Japan)
OF03813A Carton Box BX-300E
OF03674C Packing
DAO3800A Extension Cord
0D04450A Owner’s Manual BX-300 (U.S.A., Canada & Australia)
0D04451A Owner’s Manual BX-300 (Japan)
DA03801A Owner’s Manual BX-300E & BX-300 (Others)
2. TEST TAPES AND GAUGES
(1) 400 Hz Level Tape (DA09005B)
(2) 1kHz Track Alignment B Tape (DA09087B)
(3) 10 kHz PB Frequency Response Tape (DA09003B)
(4) 15 kHz PB Frequency Response Tape (DA09002B)
(5) 20 kHz PB Frequency Response Tape (DA09001B)
(6) 15 kHz Azimuth Tape (DA09004B)
(7) 3kHz Speed and Wow/Flutter Tape (DA09006C)
(8) Tape Travelling Cassette (DA09071A)
(9) Reference EXII Tape (DA09066B)
(10) Reference SX Tape (DA09025B)
(11) Reference SX-E Tape (DA09086A)
(12) Reference ZX Tape (DA09037B)
(18) EH Tilt Check Gauge S (DA09088A)
(14) Stroke Check Gauge S (DA09090A)
(15) Tape Guide Height Check Gauge S (DA09091A)
(16) Tilt Check Gauge S (DA09039B)
(>)
BRE RN ERE]
“¢

3.
MECHANICAL
ADJUSTMENT
3.1,
Record
Head
and
Playback
Head
Tilt
Adjustment
Remove
the
Cover
Plate
Ass’y
by
loosening
two
screws,
Refer to Fig. 3.1.
(1)
Remove
the
pad
lifter
from
the
playback
head.
(2)
Load
a
Tilt
Check
Gauge
S
in
the
cassette
deck,
(3)
Clip
the
grounding
terminal
of
the
Tilt
Check
Gauge
with
one
end
of
the
cord
with
clip,
and
the
chassis
of
the
cassette
deck
with
the
other
end.
(4) Remove both of the Height Gears,
(5)
Set
the
cassette
deck
in
Play
mode.
Check
to
insure
whether
the
Beacons
Playback
Head
“Upper”
or
“Lower”
and
Record
“Head
“Upper”
or
“Lower”
are
illuminating.
In
order
not
to
give
damages
onto
the
head
surfaces,
push
both
of
slide
knobs
of
the
Gauge
to
away
from
the
heads,
then
return
them
to
the
original
place
to
be
in
contact
with
record
head
and
playback
head
surfaces
after
Play
mode
is
securely
locked.
(6)
Beacon
Playback
Head
*“‘Lower’’
will
light
on
when
height
.
adjustment
screw
(PH)
turned
counterclockwise
but
Play-
back
Head
“‘Upper’
when
clockwise.
Adjust
so
that
both
“Upper”
and
“Lower”
will
light
on
even
when
you
move
the
slide
knob
away
from
the
heads
and
then
return
it
to
the
original
place.
(7)
Same
procedures
will
apply
to
the
Beacons
Record
Head
“Upper”
and
“Lower’’,
except
for
the
height
adjustment
screw
(RH).
(8)
Set
the
cassette
deck
in
Stop
mode
and
fit
both
of
the
serrated
Height
Gears.
Then
set
the
cassette
deck
again
in
Play
mode
and
insure
all
of
the
4
Beacons
are
illuminating.
If
not,
(4)
through
(7)
will
have
to
be
repeated
till
satisfactory
results
are
obtained.
(9)
Mount
the
pad
lifter
on
the
playback
head.
3.2. Head Base Stroke Check
Remove the Cover Plate Ass’y.
Refer to Fig. 3.2.
Note:
Before
you
conduct
this
adjustment,
adjust
with
a
“Tilt
Check
Gauge
S”
to
insure
freedom
from
tilt
on
the
play-
back
head
and
record
head.
(1)
Load
a
Stroke
Check
Gauge
S
in
the
cassette
deck,
(2)
Move
Record
Head
Indicator
and
Playback
Head
Indicator
to
the
direction
of
arrow
mark
“A”
with
your
finger
tip
and
then
set
the
cassette
deck
in
Play
mode.
Then
slowly
release
the
Indicators
and
insure
whether
each
of
the
Indicators
is
in
contact
with
record
and
playback
heads.
(3)
Check
to
insure
whether
the
line
“P”
on
the
Playback
Head
Indicator
meets
the
central
line
on
the
Indicator
Plate.
(4)
Check
to
insure
whether
the
line
“P”
on
the
Playback
Head
Indicator
locates
between
the
2
lines
on
the
Record
Head
Indicator,
thus
check
can
be
made
on
record
head
stroke.
3.3.
Erase
Head
Stroke
Adjustment
and
Tape
Guide
Height
Check
Remove
the
Head
Mount
Base
Ass’y
and
the
Cover
Plate
Ass’y,
Refer
to
Fig.
3.3.
(1) Erase Head Stroke Adjustment
(a)
Load
a
Tape
Guide
Height
Check
Gauge
S
in
the
cassette
deck,
(b)
Set
the
cassette
deck
in
Play
mode,
thus
check
can
be
made
on
erase
head
stroke
through
the
EH
Stroke
Indicator,
(ec)
Check
to
insure
whether
the
erase
head
surface
is
aligned
with
red
line
on
the
EH
Stroke
Indicator.
If
not,
adjust
the
erase
head
stroke
by
loosening
screw
A
that
assembles
erase
head
with
erase
head
plate.
(d)
After
completion
of
adjustment,
screw
A
shall
be
locked
with
lock
tight
paint,
(2) Supply Tape Guide Height Check
(a)
Load
a
Tape
Guide
Height
Check
Gauge
§
in
the
cassette
deck,
(b) Set the cassette deck in Play mode,
(c)
Slide
the
Supply
Tape
Guide
Check
Bar
down
against
the
supply
tape
guide,
and
check
to
insure
that
the
Supply
Tape
Guide
Check
Bar
is
accepted
by
the
supply
tape
guide.
(3) Take-up Tape Guide Height Check
(a)
Load
a
Tape
Guide
Height
Check
Gauge
S
in
the
cassette
deck.
(b) Set the cassette deck in Play mode,
(c)
Slide
the
Take-up
Tape
Guide
Check
Bar
down
against
the
take-up
tape
guide,
and
check
to
insure
that
the
Take-up
‘Tape
Guide
Check
Bar
is
accepted
by
the
take-up
tape
guide.
Height
Gear Stopper (RH)
Height Geor (RH)
Height Geor (PH)
Play Mode
Fig, 3.3
Height Adj, Screws(PH!
Take-up Tape Guide Check Bar

3.4. Erase Head Height and Tilt Adjustment
Refer to Fig. 3.4.
qd)
(2)
(3)
(4)
(5)
Remove the Cassette Case Ass’y, Head Mount Base Ass’y and
Cover Plate Ass’y.
Load an EH Tilt Check Gauge S in the cassette deck.
Set the cassette deck in Stop mode.
Check to insure whether one of the 3 Beacons is illuminating.
Look down the mirror and slowly turn the Screw “Height”
counterclockwise (or clockwise) so that the two horizontal
lines on the mirror will become superposed on the line (in
different color) of the erase head, and check to insure
whether the first Beacon is illuminating.
Turn Screw “Tilt” counterclockwise (or clockwise) to light
on the second Beacon, Excessive turing will] cause the first
(6)
(7)
(8)
Beacon to light off, Adjustments of Screw “Tilt” will there-
fore be conducted till both of the first and the second
Beacons iJuminate.
Turn Screw “Azimuth” counterclockwise (or clockwise) to
light on the third Beacon, Excessive turning will cause either
the first or the second Beacon to light off, and therefore
adjust Screw “‘Azimuth’’ until all of the 3 Beacons illuminate.
Check to insure whether the horizontal line on the mirror
corresponds to that on the erase head. If not, (4) through (7)
will have to be repeated till satisfactory results are obtained,
After completion of adjustment, 3 pes. of screws shall be
locked with lock tight paint.
Note:
Before
use
of
this
gauge,
check
to
insure
freedom
from
dust
Fig. 3.4
3.5. Playback Head and Record Head Height Adjustment and (2)
Azimuth Alignment (a)
Refer
to
Fig.
3.5.
(b)
(1)
(a)
b)
(ec)
(a)
(e)
(f)
Playback Head Height Adjustment and Azimuth Alignment
Set the Monitor switch to Tape, then connect a VTVM to the
Output Jacks,
Load a 1 kHz Track Alignment Tape, then set the cassette
deck in Play mode,
Turn the PH Height Gear until the outputs of both channels
become minimum.
Load a 15 kHz Azimuth Tape, then set the cassette deck in
Play mode,
Turn the PH Azimuth Alignment Screw until the outputs of
both channels become maximum,
Repeat above steps (b) through (e) one or two times to
obtain optimum performance.
PHHeight Adjustment
PH Azimuth Alignment
(c)
(a)
(e)
69)
(8)
or dirts, or overflow in the groove of the erase head surface.
Record Head Height Adjustment and Azimuth Alignment
Set the cassette deck in Stop mode.
Set the Monitor switch to Tape, Eq. switch to 70 és and Tape
Selector switch to ZX.
Load a reference ZX tape and connect a VTVM to Output
Jacks,
Feed in 400 Hz (0 dB) to the Input Jacks,
Set the cassette deck in Record and Play mode and turn the
RH Height Gear until the outputs of both channels become
maximum,
Feed in 15 kHz (—20 dB) to the Input Jacks and turn the RH
Azimuth Alignment Screw until the outputs of both channels
become maximum.
Repeat (d) to (f) one or two times to obtain optimum per-
formance,
RH Height Adjustment
RH Azimuth Alignment
Fig. 3.5

3.6, Pressure Adjustment of Take-up Pressure Roller
Refer to Fig. 3.6.
(1) Set the cassette deck in Play mode,
(2) Measure the torque of the Take-up Pressure Roller and check
whether the torque is in a range of 320 +50 g-cm.
(3) If torque is out of the range, correct it by changing the instal-
lation point of the Pressure Roller Spring.
Fig. 3.6
3.7. Tape Travelling Check
Load and playback a Tape Travelling Cassette and check the
following:
(1) Tape is in contact with heads sufficiently.
(2) Tape waving is small on the heads and pressure rollers.
(3) Tape is free from waving or slippage from the tape guides.
3.8. Eject Damper Adjustment
Refer to Fig. 3.8. Load a cassette tape, and with opening the
Cassette Case by pressing the Eject button and closing it by hand,
adjust the speed of damper action by the Adjustment Screw.
Fig. 3.8
3.9. Reel Motor Speed Adjustment in Play Mode
(1) To warm-up the cassette deck, load a C-60 cassette tape and
set the cassette deck in Play mode.
(2) After more than four minutes, load a torque meter TW-211
(made by Sony) and set the cassette deck in Play mode.
(3) Adjust VR601 on the Main P.C.B. Ass’y to obtain exactly
50 g-cm on the torque meter.
3.10. Tape Speed Adjustment
Refer to Fig, 3.9.
(1) Set the Pitch Control Knob on the Front Panel to its mechan-
ical center position.
(2) Connect a frequency counter to the Output Jacks,
(3) Load a 3 kHz Speed and Wow/Flutter Tape and play it back,
(4) Adjust VR101 on the Motor P.C.B. Ass’y to obtain 3,000 Hz
on the frequency counter.
CCW: Motor drives fast.
Cw: Motor drives slowly.
a
2
a
2
Q
Q
Q
5
Dd
Increase ar
Motor PC.8. Assy
Decrease
Fig. 3.9
3.11. Lubrication
The tape transport is of a lubrication-free type mechanism. When
the following parts are replaced, apply the specified lubricant.
(1) Molykote @) Grease (X5-6020)
Cam Motor Pulley
Thrust portion on the Capstan Shaft
(2) FLOIL GB-TS-1
Washer between Reel Hub Ass’y and Back Tension Spring
(3) Diamond Oil (EP56)
Reel Hub Shaft
(4) Anderol 456
Capstan Shaft
Note: We suggest that you use the above specified lubricant or
equivalent type.
The company dealing in the above lubricant is as follows:
(a) Molykote (R) Grease (X5-6020)
Dowcorning Co., Ltd., 1-15-1 Nishishinbashi, Minato-
ku, Tokyo, Japan
(b) FLOIL GB-TS-1
Kanto Chemicals Co., Ltd., 2-7 Kanda Sakuma-cho,
Chiyoda-ku, Tokyo, Japan
(c) Diamond Oil (EP-56)
Mitsubishi Oil Co., Ltd., 1-2-4 Toranomon, Minato-ku,
Tokyo, Japan
(d) Anderol 456
Toyo Kokusai Oil Co., Ltd., 3-3-5 Hatchobori, Chuo-
ku, Tokyo, Japan

4. PARTS LOCATION FOR ELECTRICAL ADJUSTMENT
Main PC.B.
VRI01 VR201
Playback Level
6)
VR60I
rPeaking
Reel
Motor
Speed
(Play)
L102
L204
MPX Filter
T _
:
Bias Trop
(Record)
TP202©)
TP201@
TP101I®
TP102©
L108
[oe]
L104
VR202
VR204
& s[9]
©L
(QL vazos
CL
EX
x
zx Record Level
3
18) 19
vR102
VRI03
VRI04
Meter Amp.P C.B.
Tape Switch P C.B.
Fig. 4

5. ELECTRICAL ADJUSTMENTS
Notes: 1. Electrical adjustment should be performed after mechanical adjustment is completed.
2.
Before
adjustment,
set
the
Bias
Tune
control
and
the
Pitch
control
on
the
Front
Panel
to
their
mechanical
center
positions,
5.1. Adjustment Instructions
REMARKS
1,
Set
the
Pitch
Control
to
its
mechanical
center
position.
2. Adjust VR101 to obtain 3 kHz +0.5% on
the frequency counter,
Output Jacks MPX SW -—ON
Input Jacks
Play back
1 kHz Track Monitor SW — Tape
VTVM to Eq, SW — 70 us
Alignment B
Tape Output Jacks =| Dolby NR SW — OFF
MPX SW — OFF
Playback
Head Track
Playback
Monitor SW — Tape
Eq. SW — 70 us
Dolby NR SW — OFF
MPX SW — OFF
VTVM to
Output Jacks
Head 15 kHz
Azimuth Tape
Evpene
400
Hz
Level
VTVM
to
Calibration
|
T@Pe
Output
Jacks
Same as above
400 Hz Level
Playback
Frequency Monitor SW — Tape
Frequency | Response Tape | yryn to Tape SW — SX
15 kHz PB
t Frequency
Response Tape
20 kHz PB
Frequency
Response Tape
Output Jacks Eq. SW — 70us
Dolby NR SW — OFF
MPX SW — OFF
Response
Adjustmen
SIGNAL OUTPUT ADJUST-
STEP ITEM SOURCE | CONNECTION MODE MENT
3 kHz Speed
1 Tape Speed | and olson Play back Motor P.C.B.
Adjustment | Wow/Flutter Output Jacks Eq. SW — 70 us VR101
Tape P
Meter Amp.
Meter Level | 400 Hz to VTVM to F a
2 Calibration | Input Jacks Output Jacks Monitor SW — Source is 108.VR 208 r
5.
+
2
: 19 kHz +100 Monitor SW — Source A
MPX Filter VTVM to Main P.C.B.
3
Adjustment
Hz
to
Dolby
NR
SW
—
OFF
L102,L202
3.
PH Height Gear
Playback Head
Azimuth
Alignment
Screw
Main P.C.B.
VR101,VR201
Main P.C,B.
R109,R209
R110,R210
1. Set the Output Level control to max.
2. Feed in 400 Hz, then adjust the Input Level
controls to obtain 1.0 V ~—4 dB on the
VTVM.
3. Adjust VR108 (VR208) so that the 0 dB
segment of the level meter starts to il-
luminate,
Adjust the Input Level control to obtain
1.0 V +1 dB on the VTVM and check
to insure that the upper segment of the
O dB segment starts to illuminate.
Set the Output Level control to max,
. Adjust the Input Level controls to obtain 1
V on the VTVM.
Set the MPX Filter switch to ON, then
adjust L102 (L202) to obtain the minimum
reading on the VTVM (the minimum read-
ing will be less than —30 dB),
Adjust the PH Height Gear to obtain minimum
readings for both channels on the VT VM. Refer
to “Playback Head Height Adjustment and
Azimuth Alignment” in item 3.5,
Adjust the Playback Head Azimuth Alignment
Screw to obtain maximum readings of both
channels on the VTVM, Refer to “Playback
Head Height Adjustment and Azimuth Align-
ment” in item 3.5.
Note: Repeat steps 4 and 5 one or two times to
obtain optimum performance,
1. Set the Output Level control to max.
2. Adjust VR101 (VR201) to obtain 1.0 V on
the VTVM.
. Load a 400 Hz level tape and play it back.
Adjust the Output Level control to a certain
level (0 dB for example),
2, Load 10 kHz, 15 kHz and 20 kHz PB fre-
quency response tapes and adjust the play-
back head azimuth to obtain maximum
levels on the VTVM with each tape.
Short R109 (R209) and/or R110 (R210) to
obtain the following levels against the level
for the 400 Hz level tape.
10 kHz: —20 dB —2 dB to +2 dB
15 kHz: —20 dB —2 dB to +3 dB
20 kHz: —20 dB —2 dB to+4 dB
Refer to ‘Playback Frequency Response
Adjustment”’ in item 5,2.
3. Conduct step 5 “Playback Head Azimuth
i ent’’.
VTVM across
the additional Record, Pause
0.1 2 resistor Monitor SW — Source
Oscillation
Frequency and Tape SW — ZX
and Erase Frequency Eq. SW — 70 us
Current Counter to Dolby NR SW — OFF
Adjustment CN3-lon Tape |MPX SW —-OFF
Switch P.C.B,
Record
Amplifier
Pha
Equalizer
|
(—20
dB)
to
Adjustment
|
put
Jacks
VTVM to
TP101, TP201
on Main P.C.B.
Same as above
Bias Trap
Adjustment | Remove
(Record input signals
VTVM to
TP102, TP202
on Main P.C.B.
Same as above
Tape Switch
P.C.B.
T301
R301,R302
Main P.C,B.
L104,L204
1, Connect an additional 0.1 2 resistor in
series to the Erase Head, then connect a
VTVM across the resistor.
2. Adjust T301 to obtain 105 kHz on the fre-
quency counter,
3. Check the erase current by the VTVM.
Erase current will be in a range of 310 mA
to 400 mA (typically approx. 350 mA). If
erase current is not sufficient, increase it by
shoring either R301 or R302.
4. After completion of the erase current
adjustment, re-check the bias oscillation
frequency.
. Remove the additional 0.1 © resistor.
5
1. Remove the bias-cut-jumper from the dip
side of the Tape Switch P.C.B. Ass’y.
2, Adjust L104 (L204) to obtain approx. +16
dB at 23 kHz on the VTVM.
3. Re-solder the bias-cut-jumper.
Main P.C.B.
L105,L205
Adjust L105 (L205) to obtain minimum read-
ing on the VT VM.

Record, Playback
Monitor SW — Tape
Tape SW — ZX
Eq. SW — 70 us
Dolby NR SW — OFF
MPX SW — OFF
VTVM to
Output Jacks
400 Hz (0 dB)
to Input Jacks
11 Head Height RH Height Gear
Adjustment
to
Record
< 15 kHz (—20 Record Head
12 Head dB) to Input bra eis . ck Same as above Azimuth
Azimuth Jacks urpUswacks Alignment Screw
Alignment
1.
2.
3.
4,
Main P.C.B.
(Level)
Record, Playback ZX:
Tone — 400 Hz/ VR104,VR204
15 kHz Sx:
Record
Monitor
SW
—
Source/|
VR103,VR203
7.
Level
400
Hz
and
Tape
EX:
Calibration as ae VTVM and Tape SW — BxISe! VR102,VR202
18
|
and
10
kHz/20
Dig
rion
Meer
ng
sw
=
70
ps
Tape
Switch
Recording
|
x+12
(—20
dp)
|
*
Output
Jacks
(ZX/SX)
|P.C.B
8
Adjustment | ‘© Input Jacks 120 us (EX)| (Biss)
Dolby NR SW — X:
C-Type/B-Type/
OFF
MPX SW — OFF
VR107,VR207
SX:
VR106,VR206
EX:
VR105,VR205 1/11,
Record, Playback
Monitor SW — Source/
Tape
Tape SW — ZX/SX/EX
Overall 400 Hz (0 dB)
d 20 Hz to A
Frequency | 22 VTVM to _ Main P.C.B.
14 [Response | 20072 4. [Output Jacks | Ba. SW (2kisxy | 1104,L204 é
Adjustment | Faout Jacks 120 us (EX) :
Dolby NR SW — OFF
MPX SW — OFF 7
8
SIGNAL OUTPUT ADJUST-
sree | em SOURCE CONNECTION MODE MENT REMARKS
Adjust the RH Height Gear to obtain maximum
readings of both channels on the VTVM. Refer
Azimuth Alignment” in item 3.5,
Adjust the Record Head Azimuth Alignment
Screw to obtain maximum readings of both
channels on the VT VM. Refer to “Record Head
Height Adjustment and Azimuth Alignment” in
item 3.5,
Note: Repeat steps 11 and 12 one or two times
Adjustment should be made in the order of ZX,
SX and EX.
. Adjust Record Cal! VR104 (VR204) for
- Feed in 400 Hz (0 dB), then record and play
. Check to insure whether the total harmonic
. If above is not sufficient, repeat 6 to 14 till
. Set the Monitor switch to Source.
- Conduct step 13 “Record Level Calibration
. If above is not sufficient, precise re-adjust-
“Record Head Height Adjustment and
to obtain optimum performance.
Set the Monitor switch to Source and Dolby
NR switch to C-Type.
Feed in 400 Hz, then set the Input Level
controls to obtain 0 dB (1 V) on the VTVM.
Set the Monitor switch to Tape.
Load a reference ZX tape, reference SX or
SX-E (for BX-300E) tape and reference
EXII tape.
ZX, VR103 (VR203) for SX and VR102
(VR202) for EX to center position,
it back.
Adjust Bias VR107 (VR207) for ZX,
VR106 (VR206) for SX and VR105
(VR205) for EX to obtain the maximum
readings on the VTVM.
Feed in 15 kHz (—20 dB), then adjust Bias
VR107 (VR207), VR106 (VR206) and
VR105 (VR205) to obtain the same
readings as source monitor levels on the
VTVM.
Feed in 400 Hz (0 dB), then adjust Record
Cal, VR104 (VR204), VR103 (VR203) and
VR102 (VR202) to obtain 0 dB on the
VTVM.
Repeat above 7 and 8 two or three times to
obtain optimum performance.
Set the Dolby NR switch to OFF.
Feed in 10 kHz (—20 dB) and 20 kHz (—20
dB), then record and play them back, Check
to insure that the levels are within —20 dB
+3 dB against the levels in Dolby NR
C-Type.
Set the Dolby NR switch to B-Type.
Feed in 10 kHz (—20 dB) and 20 kHz (—20
dB), then record and play them back. Check
to insure that the levels are within —20 dB
+3 dB against the levels in Dolby NR OFF.
distortion is less than 0.9% for ZX tape and
1,0% for SX/SX-E and EXII tapes.
satisfactory results are obtained.
Feed in 400 Hz (0 dB) and adjust the Input
Level controls to obtain 0 dB (1 V) on the
VTVM.
pha the Generator output level to —20
B.
Set the Monitor switch to Tape, then record
and play it back.
Feed in 20 Hz to 20 kHz (—20 dB), and
check to insure whether the output levels
are within —20 dB +3 dB.
If above is not sufficient, adjust L104
(L204) to obtain approx. —20 dB on the
VTVM at 20 kHz.
and Recording Bias Current Adjustment’,
ment of step 7 “Playback Frequency
Response’’, replacement of Playback Head
or Record Head, check on item 3.7 “Tape
Travelling Check’ will be required.

5.2, Playback Frequency Response Adjustment The peaking portion of the equalization curve compensates the
Figs,
5.1
and
5.2
show
the
playback
amp.
circuit
for
adjusment
gap
loss
of
the
playback
head.
Peaking
level
is
varied
by
the
short
and
the
playback
equalization
curve.
circuit
of
R109
(R209)
and/or
R110
(R210)
on
the
Main
P.C.B.
This adjustment
will be
required
if
playback level is
not
sufficient
Ass’y.
during playing back a 20 kHz PB frequency response tape.
R109 R110 L101
(R209) (R210) ar laaiaass
390 3= 68
Play back
Head
Fig. 5.1
GAIN (dB)
approx. 2dB
approx. 2d8
approx. 2dB
FREQUENCY (Hz)
Fig. 5.2

6. MECHANISM ASS’Y AND PARTS LIST
6.1. Synthesis
HeeiNo., segs et en
Synthesis
Serial No.: A12701001 -
HA04645A
HA04644A
0HO04342A
OHO03737A
HA04662A
HA04660A
HA04661A
Cassette Case Cover Ass’y
BX-300 (U.S.A., Canada,
Australia & Others) &
BX-303E
Cassette Case Cover Ass’y BX-300
(Japan)
Volume Knob
Volume Knob Base
Front Panel Ass’y BX-300E
Front Panel Ass’y BX-300 (U.S.A.,
Canada, Australia & Others)
Front Panel Ass’y BX-300 (Japan)
10
Schematic
Ref. No,
[rane | pacion [a
0J304628A
0H04427A
0H04156B
0M04377B
0J04629A
0J04762A
OJ03564A
0E03054A
0E03032A
OE00868A
OEO0865A
Top Cover Cushion (Front)
Meter Scale
Top Cover
Caution Label
Top Cover Cushion (Back)
Synthesis Mechanism Ass’y
Bottom Cover
Leg TH
BT 3x8 © Countersunk
BT 4x8 @Pan Washer-faced
BT 3x8 @ Binding
BT 3x10 © Binding
POP REED OO

6.2 Front Panel Ass’y (A01)
HAO4660A | Front Panel Ass’y BX-300 1
(U.S.A., Canada, Australia &
Others)
HA046614A | Front Panel Ass’y BX-300 (Japan)
HA04662A | Front Panel Ass’y BX-300E
Serial No,: A12701001 -
Schematic
Ref. No.
A0l
0H04420A | Front Panel BX-300 (U.S.A.,
Canada, Australia & Others)
0H04447A | Front Panel BX-300 (Japan)
0H04421A | Front Panel BX-300E
0H04251C | Meter Cover
0H04241A | Counter Cover
Fig. 6.2
6.3 Synthesis Mechanism Ass’y (A02)
LIZ LI6
Lor

Schematic
Ref, No, Part No.
01 HA04570A
02 OJ04765A
03 HA04632A
04 0H04248A
05 BA05366A
06 0J04768A
07 BA05365A
08 0H04247B
09 0H04286B
10 0J04703A
11 0J04704A
12 BA05392A
»13 0H04243A
“14 BA05389A
BA05388A
BA05387A
15 0J04841A
16 0J04839A
17 0B08515A
18 BA05428A
19 HA04631A
20 0HO04415A
21 CA08650A
22 BA05400A
23 0B82311A
24 OBO09685A
25 BA05361A
26 BA05353B
BA05353B-E
BA05353A
ice
27 HA04622A
HA04623A
HA04624A
HA04625A
HA04626A
HA04627A
28 0J04773A
29 BA05499A
30 0B90012A
_ 0B02240A
- 0M04391A
- 0B08349B
- OB08962A
- 0B08961A
- 0M04595A
Lol OEO0O766A
L02 OE00868A
L03 OE00857A
L04 0E03074A
L05 0E03212A
L06 OB08583A
L07 —
Los =
Log 0E03072A
L10 0E00835A
L11 0E00824A
0E03202A
Description
Synthesis Mechanism Ass’y
Serial No,: A12701001 -
Eject Button Ass’y
Spring
Front Chassis Ass’y
Push Switch Button
Tape Switch P.C.B. Ass’y
Earth Plate
Dolby NR Switch P.C.B. Ass’y
Slide Volume Knob
Slide Volume Plate
P.C.B, Spacer A
P.C.B. Spacer B
Volume P.C.B. Ass’y
Power Switch Button
Power Switch P.C.B. Ass’y
BX-300 (Australia & Others)
& BX-300E
Power Switch P.C.B. Ass’y
BX-300 (U.S.A. & Canada)
Power Switch P.C.B. Ass’y
BX-300 (Japan)
Side Chassis (L)
P.C.B. Holder
(Serial No.: A12702001 - )
Insu-Lock
Fuse P.C.B. Ass’y (Not including
fuses)
Cover Plate Ass’y
Head Mount Cover
Mechanism Ass’y
Earth Wire Ass’y
3P-H Connector
Carbon Resistor 2.2K 1/6W J
Meter Amp. P.C.B. Ass’y
Main P.C.B. Ass’y BX-300
(Serial No.: A12702001 - )
Main P.C.B. Ass’y BX-300E
(Serial No.: A12702001 - )
Main P.C.B. Ass’y BX-300
(Note 1)
(Serial Nos,: A12701001 -
02000)
Main P.C.B. Ass’y BX-300E
(Note 1)
(Serial Nos,: A12701001 -
02000)
Rear Panel Ass’y BX-300E
(UK)
Rear Panel Ass’y BX-300
(U.S.A. & Canada)
Rear Panel Ass’y BX-300 (Japan)
Rear Panel Ass’y BX-300 (Others)
Rear Panel Ass’y BX-300
(Australia)
Rear Panel Ass’y BX-300E
(220V Class 2)
Side Chassis (R)
Input Amp. P.C.B. Ass’y
(Serial No,: A12702001 - )
Insu-Lock 140mm
Fuse T1.25A BX-300E & BX-300
(Australia)
Fuse Label T1.25A BX-300E &
BX-300 (Australia)
Fuse Clip BX-300E & BX-300
(Australia)
Fuse 2.5A BX-300 (U.S.A.,
Canada & Others)
Fuse 2.5A BX-300 (Japan)
Fuse Caution BX-300 (U.S.A. &
Canada)
M3x8 ® Binding
BT 3x8 % Binding
BT 3x6 @ Binding
BT 2.6x8 © Binding with
Toothed-iock Washer
BT 2.6x6 © Binding with
Toothed-lock Washer
Plastic Rivet
Nut
Washer
M2.6x6 @ Binding
BT 3x25 ®Pan
BT 2.6x6 @ Pan (Black Chromate)
M2.6x3 © Binding
(Black Chromate)
PRRE PRO H eR OH RE
iy
BH REE ee eee Bo fe ee
Schematic
Ref. No.
L14
L15
L16
Part No.
Description
OE03217A
OEO0607A
0E00921A
OE03238A
HA04632A
e
NNR PRE BF NNWO BN ND RR ND ee eB Bee eo
antany
12
HAO4615A
OB08511A
OJ04611A
BA05440A
BA05390A
0H04242A
BA05391A
BA05399A
OEO0868A
OEO00857A
6.4. Front Chassis Ass’y (B01)
BT 4x8 © Binding
M3x8 © Pan (3A)
BT 3x8 6 Binding
(Black Chromate)
Fiber Washer 4x10x1
Note 1:
available as a spare part.
BA05353B-E).
Front Chassis Ass*y
Serial No,: A12701001 -
Front Chassis Sub Ass’y
Headphone Jack
Headphone Plate
Pitch Controller Ass’y
Control Switch P.C.B. Ass’y
Slide Switch Knob
Counter P.C.B. Ass’y
Indicator Ass’y
BT 3x8 © Binding
BT 3x6 © Binding
The old type Main P.C.B. Ass’y is not
If replacement is necessary, please
order Input Amp. P.C.B. Ass’y (BA0-
5499A) and P.C,B, Holder (0J04839.A)
(for mounting Input Amp. P.C.B.
Ass’y) together with the new type
Main P.C.B. Ass’y (BA05353B/
COOK Rw EERE

6.5. Cover Plate Ass’y (B02)
HA04631A
|
Cover
Plate
Ass’y
0C80017A
|
Record
Protect
Lever
1
Serial
No.:
A12701001
-
é1
0C80627A
|
Mechanism
Chassis
1
62
0C80022A
|
Cassette
Hold
Spring
1
01
0M04392A
|
Cassette
Label
Gold
63
CA80011A
|
Shut-off
P.C.B.
Ass’y
1
02
0H04437B
|
Cover
Plate
64
0C80012A
|
Eject
Sensor
1
~
65
CA80204A
|
Brake
Ass’y
1
CA08650A
|
Mechanism
Ass'y
66
0C80628B
|
Brake
Spring
B
1
Serial
No.:
A12701001
-
67
OC80630A
|
Brake
Arm
Collar
1
68
OC80629A
|
Brake
Arm
1
01
CA80206A
|
D.D.
Motor
Ass’y
1
69
0C80030A
|
Reel
Motor
Holder
1
02
OC80026A
|
Cam
1
70
CA80205A
|
Reel
Motor
Ass’y
1
03
0C80028A
|
Control
Motor
Holder
1
71
0C80631A
|
5P-H
Connector
1
04
CA80007A
|
Control
Motor
Ass’y
1
72
0C80632A
|
9P-H
Connector
bs
05
CA80200A
|
Cassette
Case
Ass’y
1
73
0C80037A
|
Insu-Lock
3
06
0C08762A
|
Head
Height
Adjustment
Gear
2
14
0C80635A
|
Idler
Pulley
1
07
0C08761A
|
Head
Height
Adjustment
Screw
4
=
0C80634A
|
Capstan
Belt
1
08
0C08763A
|
Azimuth
Alignment
Screw
2
L01
0E03044A
|
FT2.5x20
®Pan
1
09
OC80605A
|
Wire
Clamper
1
LO2
OE00976A
|
M2x5
@Pan
5
10
CA08637A
|
Head
Mount
Base
Sub
Ass’y
1
LO3
OE00025A
|
Spring
Washer
2mm
2
11
CAO08659B
|
R-3L
Record
Head
Ass’y
1
L04
0E00117A
|
Washer
2.2x4.3x0.4
5
12
0C08776A
|
Head
Plate
Spring
(L)
1
L05
OEOO866A
|
M2.6x4
©
Binding
1
13
OC80606A
|
4P-H
Connector
1
LO6
0C08774A
|
Plate
Washer
L
1
14
CAO08658B
|
P2H-L
Playback
Head
Ass’y
1
L07
0C08773A
|
Plate
Washer
R
1
15
0C08775A
|
Head
Plate
Spring
(R)
1
LOo8
OE03228A
|
FT3x4
®Pan
1
16
0C80607A
|
4P-H
Connector
1
Log
0E03232A
|
M1.7x7
®
Pan
1
17
0C80003A
|
Head
Base
Hold
Plate
1
L10
0E03222A
|
Washer
1.8x3.8x0.3
1
18
0C80004A
|
Steel
Ball
3mm
1
Lil
OE00691A
|
M2x3
@
Pan
(Chromate)
2
19
GA022014
|
E-4F
Erase
Head
1
L12
0E03234A
|
M2x3
@
Pan
(Nickel)
2
20
OC80608A
|
2P-H
Connector
1
L13
0E00222A
|
E-Ring
2mm
2
21
OCO8768A
|
E.H,
Hold
Plate
1
L14
0E03035A
|
TP
2x3,2
Truss
1
22
OCO8889A
|
E.H.
Hold
Plate
Tapering
Spring
2
L15
OE03049A
|
Washer
1.8x3.2x0.5
2
23
OCO08886A
|
E.H.
Hold
Plate
Spring
1
L16
OE03226A
|
Washer
2.1x4.5x0.1
3
24
OCO8771A
|
Tape
Guide
Plate
1
L17
OE00224A
|
M2x3
Cup
Point
1
25
CA08638A
|
Head
Base
Sub
Ass’y
1
L18
0E03043A
|
FT
2.5x10
®
Pan
2
26
0C80007A
|
Steel
Ball
2mm
3
L19
0E03225A
|
Washer
1.8x3.2x0.5
1
27
CA8O0005A
|
T.
Pressure
Roller
Arm
Ass’y
1
L20
0E00181A
|
E-Ring
3mm
1
28
OC80609A
|
T.
Pressure
Roller
Arm
Spring
1
L21
0E03235A
|
Plastic
Washer
2x5x0.25
1
29
0C80027A
|
Mode
Switch
1
L22
0E03052A
|
CS
Stopper
Ring
2.4mm
2
30
OC80010A
|
Cassette
Case
HolderR
1
L23
QOE03229A
|
FT
2.5x6
@Pan
13
31
OC80610A
|
Cassette
Case
Spring
1
L24
QE03236A
|
M2x5
@
Pan
(2A)
4
382
O0C80611A
|
Head
Base
Spring
1
L25
0E03227A
|
Washer
2.7x5x0.5
2
33
CA80201A
|
T,
Reel
Hub
Ass’y
1
L26
0E03231A
|
M2x30
@Pan
2
34
0C80612A
|
Spring
Holder
2
L27
0E03041A
|.
FT
2.5x4
®Pan
2
35
OC80613A
|
T.
Reel
Hub
Spring
1
L28
0E03237A
|
Nut
Hex.
M2.6
1
36
CA80202<A
|
S,
Reel
Hub
Ass’y
1
L29
OE03233A
|
Washer
2.6x8x1
1
37
OC80614A
|
S.
Reel
Hub
Spring
1
L30
0E03230A
|
ST
2.6x12
®Pan
1
38
OC80615A
|
Pressure
Roller
Plate
1
L31
OE03045A
|
M2.6x3
@
Binding
2
39
CA80203A
|
S,
Pressure
Roller
Arm
Ass’y
1
L32
OE00694A
|
Nut
Hex.
M2
1
40
OC80616A
|
S.
Pressure
Roller
Arm
Spring
1
L33
0E03245A
|
Mylar
Washer
1.3x3.3x0.3
1
41
0C80013A
|
Lock
Lever
Spring
1
42
0C80014A
|
Lock
Lever
Collar
1
43
0C80015A
|
Lock
Lever
1
44
0C80617A
|
Back
Tension
Arm
Spring
1
45
0C80618A
|
Back
Tension
Arm
Collar
1
46
OC80619A
|
Back
Tension
Arm
1
47
0C80620A
|
Back
Tension
Pulley
1
48
0C80621A
|
Back
Tension
Belt
1
49
OC80021A
|
Eject
Lever
1
50
OC80020A
|
Eject
Lever
Spring
1
51
0C80011A
|
Eject
Sensor
Holder
1
52
CA80006A
|
Pneumatic
Damper
Ass’y
1
53
0C80019A
|
Eject
Spring
1
54
OC80018A
|
Cassette
Case
Holder
L
1
55
0C80622A
|
Switch
Hold
Plate
1
56
0C80623A
|
Switch
Plate
2
57
0C80624A
|
Switch
Collar
A
2
58
OC80626A
|
Leaf
Switch
1
0C80625A
|
Switch
Collar
B
2
13

6.6. Mechanism Ass’y (B03)
Fig. 6.6

7. MOUNTING DIAGRAMS AND PARTS LIST
Notes: 1. Mounting diagram shows a dip side view of the printed circuit board.
2. Diode is 1SS53, 181555, or 188176 unless otherwise specified.
8. Following transistors are interchangeable with each other.
a. 2SA733, 2SA608SP, 2SA1048, 2SA1175
b. 28C945, 2SC536SP, 28C 2458, 2SC2785
4, Abbreviation for part name:
TR — Transistor, SiD — Silicon Diode, GD — Germanium Diode, ZD — Zener Diode
RK — Carbon Resistor, RM — Metal Film Resistor, RF — Fail Safe Type Resistor
CE — Electrolytic Capacitor, CM — Mylar Capacitor, CC — Ceramic Capacitor, CP — PP Capacitor,
CT — Tantalum Capacitor, CF — Film Capacitor, C — Mica Capacitor
6.7. Rear Panel Ass’y (B04)
1.2. Shut-off P.C.B. Ass’y
7.1. Power Switch P.C.B. Ass’y
HA04622A
HA04623A
HA04624A
HA04625A
HA04626A
HA04627A
0H04425A
0H04424A
0H04448A
0B81001A
BA05482A
(0B08584A)
(0B82344A)
0B50029A
0B50030A
0B50031A
0B50032A
0B08348A
0B08533A
0B08219B
0B05241A
0B08093U
OB08351A
0B08037U
Rear Panel Ass’y BX-300E (UK)
Rear Panel Ass*’y BX-300
(U.S.A. & Canada)
Rear Panel Ass’y BX-300 (Japan)
Rear Panel Ass’y BX-300 (Others)
Rear Panel Ass’y BX-300
(Australia)
Rear Panel Ass’y BX-300E
(220V Class 2)
Serial No,: A12701001 -
Rear Panel BX-300E
Rear Panel BX-300 (U.S.A.,
Canada, Australia & Others)
Rear Panel BX-300 (Japan)
4P Pin Jack
8P Din Socket Ass’y (Consisting
of the followings)
8P Din Socket
8P-H Connector
Power Transformer BX-300
(Australia) & BX-300E
Power Transformer BX-300
(U.S.A. & Canada)
Power Transformer BX-300
(Japan)
Power Transformer BX-300
(Others)
Power Cord BX-300E (UK)
Power Cord BX-300
(U.S.A., Canada & Others)
Power Cord BX-300 (Japan)
Power Cord BX-300 (Australia)
Power Cord BX-300E
(220V Class 2)
Cord Bushing 4K-4 BX-300E (UK)
Cord Bushing BX-300 & BX-300E
(220V Class 2)
Fig. 6.7
re
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Schematic
Ref. No.
0J04601B
0M03948A
0B07092U
0B08583A
OE00637A
OE00907A
0E03072A
OE00921A
OE00818A
Switch Cover BX-300 (U.S.A.,
Canada, Japan & Australia) &
BX-300E
Voltage Lock Plate BX-300
(Others)
Voltage Selector BX-300 (Others)
Plastic Rivet
Washer 3.3x7x0.5
ST 4x8 © Binding
(Black Chromate)
(Black Chromate)
M3x8 © Binding
(Black Chromate)
bv oN NY NRROR FB
BA05372B
BA05373B
BA05495B
BA05374B
BA05353B
BAO05361A
BA05366A
BA05392A
BA05499A
BA05375A
BA05365A
BA05390A
BA05391A
BA05428A
8)
P.C.B. Ass’y BX-300
(Japan)
P.C.B. Ass’y BX-300
(Australia)
Set-A P.C.B. Ass’y
BX-300 (consists of
the followings)
Main P.C.B. Ass’y
BX-300
Meter Amp. P.C.B.
Ass’y
Tape Switch P.C.B.
Ass’y
Volume P.C.B. Ass’y
Input Amp. P.C.B.
Ass’y
Set-B P.C.B. Ass’y
(consists of the
followings)
Dolby NR Switch
P.C.B. Ass’y
Control Switch
P.C.B. Ass’y
Counter P.C.B. Ass’y
Fuse P.C.B. Ass’y
BA05371B
BA05374B-E
BA05353B-E
BA05361A
BA05366A
BA05392A
BA05499A
BA05375A
BA05365A
BA05390A
BA05391A
BA05428A
15
P.C.B. Ass’y BX-300E
Set-A P.C.B. Ass’y
BX-300E (consists of
the followings)
Main P.C.B. Ass’y
BX-300E
Meter Amp. P.C.B.
Ass’y
Tape Switch P.C.B.
Ass’y
Volume P.C.B. Ass’y
Input Amp. P.C.B.
lowings)
Dolby NR Switch
P.C.B. Ass’y
Control Switch
P.C.B. Ass’y
Counter P.C.B. Ass’y
Fuse P.C.B. Ass’y
BA05389A
BA05388A
BA05387A
0B60104B
0B70002A
0B08342A
0B08445A
0B08363A
0B08359A
0J04763A
OE00752A
0E00612A
CA80011A
0C80047A
OB06388A
0B06389A
0B09840A
OB09841A
to Logic Port
Power Switch P.C.B.
Ass’y BX-300
(Australia & Others)
& BX-300E
Power Switch P.C.B.
Ass’y BX-300
(U.S.A. & Canada)
Power Switch P.C.B.
Ass’y BX-300
(Japan)
Power Switch P.C.B.
Power Switch
Spark Killer BX-300
(U.S.A. & Canada)
(1)
Spark Killer BX-300
(Australia & Others)
& BX-300E (1)
Spark Killer BX-300
(Japan) qd)
Spark Killer Cover
BX-300 (Australia
& Others) &
BX-300E (1)
Power Switch
Holder (1)
Eyelet 2x3 (2)
M3x6 © Pan eer
Shut-off P.C.B. Ass’y
Shut-off P.C.B.
TR 28C2812
Photo Reflector
NJL5141
RK 680 _ Leadless
RK 18K _ Leadless

7.3. Fuse P.C.B. Ass’y
7.4. Volume P.C.B. Ass’y
BA05428A
0B60107B
Fuse P.C.B. Ass’y
Fuse P.C.B.
1IC750 OBO6369A | IC TA7612AP
IC751 0B11031A | IC TLO92
Q750 0B06013A | TR 2SA733
ZD7560,751 | OBO6191A | ZD 2.7V RD2.7E
D750,751 | 0B06181A | SiD 18853
D752,753
754,755
R750
R751,764
R752,767
R1753-762
R763
R765,768
769,772
716,777
R766
R770
R771
R773,774
OB06398A
OBO09695A
OBO9677A
0B09701A
OB09681A
OBO9709A
0B09725A
18S176
RK 5.6K 1/6WJ
RK 1K 1/6W J
1/6W J
OB09685A
OBO9717A
0B09713A
OB09737A
0B09749A
OB09651A
0B09292A
0B09281A
0B09163A
OBO9868A
0B02350A
0B02349A
0B02356A
0B81163A
BA05392A
OB60099A
0B06325B
0B31002A
0B31001A
0B09719A
OBO9695A
0B41386A
0B81011A
0B81012A
CC 150P 50V K
CE 10y 16V (BP)
CF 0.1u 50V J
JP Connector 5P
JP Connector 4P
JP Connector 12P
Wire Trap 2P S
Volume P.C.B. Ass’y
Volume P.C.B.
Photocoupler
MCD7214F
Slide Volume 100K
(A)
Slide Volume 10K
(A)x2
RK 56K 1/6WJ
RK 5.6K 1/6W J
CP 100P 100V J
Dip Mate 4P
Dip Mate 5P
Cds301
VR109,209
VR301
R101,201
301
Fig. 7.4
16

7.5, Input Amp. P.C.B. Ass’y
Fig. 7.5 Serial No.: A12702001 —
BA05499A
Input Amp. P.C.B.
Ass’y
Serial No.:
A12702001 -
0B60125A
0B06146A
0B06013A
OBO06398A
0B06676B
0B09733A
0B09653A
0B22426A
0B22313A
OB22396A
OBO9701A
0B01888A
0B09814A
0B09932A
0B09409A
0B81010A
0B81011A
BA05361A
Input Amp. P.C.B.
IC 4558DD
TR 2SA733 (P,Q)
SiD 1SS176
Inductor 36mH G
RK 220K 1/6WJ
RK 100 1/6wJ
RM 53.6K 1/6W F
5.49K 1/6W F
RK 10K 1/4WJ
CE 1yu 50V (LN)
CE 22u 16V (LN)
CP 1800P 100V G
Dip Mate 3P
Dip Mate 4P (2)
Meter Amp. P.C.B.
Ass’y
Meter Amp. P.C.B.
TR 2S8C1740S
0B60108B
0B10039A
Q101,102
201,202
Q103,203 | 0B01872A | TR 2SC945L (P,Q)
ZD101,201 | 0B12101A | ZD 5V 5C-1
D101,102 | OB06398A | SiD 1S8S176
201,202
301
VR108,208 | 0B32026A | Semi-fixed VR 220K
R101,201 | OBO09717A | RK 47K 1/6WJ
R102,202 | 0B01889A | RK 100K 1/4wWJ
R103,203 | OB09747A | RK 820K 1/6WJ
R104,204 | 0B09723A | RK 82K 1/6WJ
R105,106 | 0B09725A | RK 100K 1/6W J
108,109
205,206
208,209
R107,207 OBO9719A | RK 56K 1/6WJ
C101,201 OBO9868A | CF 0.1n 50V J
C102, +202 | 0B09148A | CE 10, 25V (LN)
CN2 0B02242A | 4P-T Post
CN8 0B81175A | B-B Connector 2P
SM12 0B81010A | Dip Mate 3P
MM15.16 0B81011A | Dip Mate 4P
FC3 0B81012A | Dip Mate 5P
0J04790A | P.C.B. Holder (1)
OE00607A
M3x8 © Pan (3A)
ql)
Pd
0B60102B
D756,757
VR750
R778
R779,780
R781
R782,783
R784
7.6.
Meter
Amp.
P.C.B.
Ass’y
CN-8
wo T+iev
o-dLine.m
an 8.
Qio3
Fig. 7.6
7.1. Dolby NR Switch P.C.B. Ass’y
BA05365A
0B06181A
0B30016A
OBO9697A
OBO9677A
0B09391A
OBO5575A
0B09713A
17
Dolby NR Switch
P.C.B. Ass’y
Dolby NR Switch
P.C.B.
SiD 18853
Semi-fixed VR
1/6W J
1/6W J
1/4w J
1/4W J
1/6W J
Fig. 7.7
R785
R786,789
790
rt
C752
mea 754
FC2
FC22, 31
SD13,DM14
OBO9695A
0B09701A
OBO1887A
0B01412A
0B01405A
OB81011A
0B81153A
0B81010A
0J04768B
0B70024A
5.6K 1/6w J
RE 10K 1/6wJ
5.6K 1/4wJ
CE 104 16V
CE ip 50V
Dip Mate 4P
Wire Trap 3PR
Dip Mate 3P
Earth Plate A (1)
Push Switch 3-Key
q@)

Schemati
Z
ea
ibe
BA05390A | Control Switch
P.C.B. Ass’y
Control Switch
P.C.B.
TR 2S8C1740S
TR 2S8C3399
TR 2SA1345
TR 2SA933S
LED TLG124A
(GRN)
LED TLR124A
(RED)
SiD 18853
SiD 1S8S176
150 1/4wJ
0B60100A
0B10030A
0B10007A
0B10003A
0B10026A
0B06334A
0B06333A
0B06181A
OB06398A
0B05795A
OBO9657A | RK 150 1/6WJ
OBO9667A | RK 390 1/6WJ
OBO9663A | RK 270 1/6WJ
0B09701A | RK 10K 1/6WJ
RK 1K 1/6W J
RK 4.7K 1/6WJ
Touch Switch 4.3mm
LED Reflector (6)
Counter P.C.B. Ass’y
OBO9677A
0B09693A
0B70004A
0304744A
BA05391A
0B60101B
OB06368A
0B10026A
R706,707
R716
SW701-709
Counter P.C.B.
IC LM6416E-106
TR 2SA933S
Counter LED
RK 220K 1/4WJ
RK 10K 1/6WJ
RK 2.7K 1/6WJ
0B12098A
0B05625A
OBO9701A
OBO9687A
220 1/6w J
OBO9661A
4.7K 1/4WJ
CC 100P 50V K
CM 0.015yu 50V J
CE 100u 10V
Slide Switch 2-2
Slide Switch 2-3
9P Socket qd)
11P Socket qd)
0B01846A
0B09282A
OB05557A
OBO5885A
0B81017A
7.8. Control Switch P.C.B. Ass’y
ed SW703" REC en
7.9. Counter P.C.B. Ass’y
cate ‘ “ an
GR aa Cae IR SEE RA Sa.
18
ASO 5 S86, AN: A
/FC-I0
7.10. Tape Switch P.C.B. Ass’y
Pore rere ia ast
$w304
L
BAO5366A | Tape Switch P.C.B.
Ass’y
— Line Amp. —
IC301 0B06443A
Q101,201 | 0B01872A
L106,206 | OBO6691A
D101,201 | 0B06398A
R101,102 | 0B09725A
201,202
R103,203 | 0B09733A
R104,204 | 0B22342A
R105,205 | 0B22308A
R106,206 | OBO9677A
R107,207 | 0OB09749A
R108,208 | 0B09701A
C101,201 0B09814A
C107,207 | 0OB09270A
IC NJM082D
TR 2SC945L (P,Q)
L-C Block
siD 1SS176
RK 100K 1/6W J
RK 220K 1/6W J
RM 9.76K 1/6W F
RM 4.99K 1/6W F
RK 1K 1/6WJ
RK 1M 1/6wJ
RK 10K 1/6WJ
CE ily 50V (LN)
CP 470P 100V J
— Miscellaneous —
OB60098B
Q301 0B01426A
Q302 0B06013A
T301 0B51047A
VR105,205 | 0B32010A
VR106,206 | 0B32009A
VR107,207 | 0B32008A
R109,209 | OB09705A
R110,210 | OB09697A
OB09653A
OB09936A
OBO09998A
OB09685A
OB09721A
0B09701A
OB09717A
R308,309 | 0B09725A
312
OBO9669A
0B01403A
0B09538A
OB09844A
Tape Switch P.C.B.
TR 2SA562 (0,Y)
TR 2SA733 (P,Q)
Bias Osc.
Semi-fixed VR 47K
Semi-fixed VR 22K
Semi-fixed VR 10K
15K 1/6WJ
6.8K 1/6WJ
100 1/6wJ
10 1/2W J
22 1lwJ
2.2K 1/6WJ
68K 1/6WJ
10K 1/6wJ
47K 1/6WJ
100K 1/6w J
470 1/6WJ
47u 16V
0.0184 100V J
1000P 50V J
CM 0.01u 50V J
Wire Trap 3P
Push Switch biog A
Earth Plate A

711.
Main P.C.B. Ass’y
=
5
2
CN re sat:
poe an .
ryote
$ Spep ore i
ee ‘ols » RG Ww
vtololo A cleeteatone
“boob.
ae
a208.
FSS"
ol.
| owes TT BT ; -—
ee og MPHIT
Pas
Fig. 7.11.1 Serial No.:;: A12702001 —
19