Technics RS-M228X User manual

ORDER NO. ARD82050143C8-20
Service
Manual
Cassette Deck
dbx
NR,
Soft-Touch
Cassette
Deck
RS-M2
28X
Gaied iene
Black Face
DO [saavaveren]
( This is the Service Manual for the |
following areas.
D)-------+ For all European areas
except United Kingdom.
titteeens For United Kingdom.
[N] --+-- For Asia, Latin America,
Middle East and Africa
areas.
| [A] e+ seeeee For Australia. |
RS-M24 MECHANISM SERIES
Specifications
Track system: 4-track 2-channel recording and playback Outputs: LINE; output level 400 mV, output impedance
Motor:
Electrical
governor
motor
2.2kQ
or
less
Tape speed: 4 8cm/s HEADPHONES; output level 125mY (82) appli-
Wow and flutter: 0.048% (WRMS), +0.14% (DIN) | cableineaapmons Impedance Oh 72208
Frequency response: Metal tape; 20 —18,000Hz Bias frequency: 89 kHz
30 —17,000Hz (DIN) Heads: 2-head system
CrO2 tape; 20—18,000Hz 1 MX head for record/playback
30 — 17,000 Hz (DIN) 1 double-gap ferrite head for erasure
Normal tape; 20 —17,000Hz Power requirements:
30
—
16,000
Hz
(DIN)
DIN]
---
AC
110/125/220/240V,
50-60
H:
Dynamic range: 110dB (at 1kHz), dbx in B] --- AC 240 V, 50Hz
Max. input level [A] --- AC 240 V, 50-60Hz
improvement:
10dB
or
more
improved
with
dbx
in
(at
1
kHz)
ee
oe
Signal-to-noise ratio: dbx in; 92 dB ia us A0V
Dolby NR in; 67dB (above 5kHz) on,
Dolby NR out; 57 dB (signal level = max. input Power consumption:
level A weighted, CrOz type tape) DyByAl --- 20W
Fast forward and : ; N] ++ 15 W
rewind time: Approx. 90 seconds with C-60 cassette tape Dimensions: 43.0cm(W) x 10.9cm(H) x 28.0cm( D)
Inputs» MIC; sensitivity 0.25 mV, applicable microphone Weight: 5.0kg
impedance 4002 — 10kQ
LINE; sensitivity 60 mV, input impedance more
than 40kQ
Specifications are subject to change without notice.
* The term dbx is a registered trademark of dbx Inc.
+* ‘Dolby’ and the double-D symbol are trademarks of Dolby Laboratories.
Te chnics Matsushita Electric Trading Co., Ltd.
P.O. Box 288, Central Os; aka Japan

RS-M228X
CONTENTS
ITEM PAGE
LOCATION OF CONTROLS AND COMPONENTS ------------ 2
DISASSEMBLY INSTRUCTION --+----cseeers sees eeeee te teeee ee eees 3
MEASUREMENT AND ADJUSTMENT METHODS
(without dbx SYSTEM) ‘ibietalerbisiaiolelala'e einitie slorw-sjateisiels ewwle eerie viele lois 5
MEASUREMENT AND ADJUSTMENT METHODS
(for dbx SYSTEM) (gE ut saiate Syste ySejeie bie ware dig 915 olan Cat sigleieretelg bate ever 11
* TROUBLESHOOTING CHART FOR dbx SYSTEM ---- 11
* ADJUSTMENT PARTS LOCATION OF dbx
SYSTEM feesccceston stoves nnd Sia teowetnn reduce tet ee teenasiy se 13
* BLOCK DIAGRAM OF dbx SECTION ------+--eeeeeeeee ee 13
* dbx SYSTEM CHECKING METHOD ..---------------e-5+ 5 14
¢ ADJUSTMENT OF dbx SYSTEM --vecececececeeeeeeeeee ees 15
* CHECKING PROCEDURE FOR PROBLEMS -.---------- 16
-
ELECTRICAL
PARTS
LOCATION
-:-:::ceccececeeeeeeteeeeeeneees
18
BLOCK:
DIAGRAM
2-:
seeds
eseeonseseocue
ttesseiag
sence
ecesce
vat
eecoess
20
ITEM PAGE
SCHEMATIC DIAGRAM
(MAIN/POWER SUPPLY SECTION) ----:++seereeeeeeeees 22
CIRCUIT BOARDS
(MAIN/POWER SUPPLY CIRCUIT BOARD) ----+----- 25
SCHEMATIC DIAGRA
(dbx SECTION) ---:-e:ceceseecee eee eeeeteeeeeeenteeneeeseereeeees 29
SCHEMATIC DIAGRAM
(FL METER SECTION) --c-eecceeeeece eet eceeseeeeeeeea seen eres 30
CIRCUIT BOARDS
(dbx/FL METER CIRCUIT BOARD) ----:++-esreerrereees 31
WIRING CONNECTION DIAGRAM .--eeeeeeeeeeeeeeeeneeer tenes 33
CABINET PARTS LOCATION <0: -e:-sseececeeeeee teste eeeereeeaees 35
MECHANICAL PARTS LOCATION -evcececcecececeteeeteeeeenee 37
MOTOR UNIT DISASSEMBLY ------:ereeceeteereeet eee eeteeea ees 40
PRECAUTIONS FOR MECHANISM UNIT ASSEMBLY ---- 40
LOCATION OF CONTROLS AND COMPONENTS
Headphones Jack (phones)
Power Switch [power (push on)}]
Eject Button (eject)
Cassette Holder
Tape Counter (tape counter)
Recording Indicator (rec)
Tape Indicator
[Auto Tape Select (NormaleCrOzeMetal)]
FL (fluorescent level) Meter
Input Level Controls
[input level (L-®-R)]
Noise Reduction Select Switch
[Noise Reduction (Dolby NR**eout
dbx] tapee (dbx| disc)]
Fast Forward/Cue Button
[ff/cue (>> )]
Rewind/
Review Button
{rew/rev ( ¢4)]
i}
i)
1
t
i}
1
Counter Reset Button i
(counter
reset)
|
Input
Select
Button
i}
i]
i}
I
i}
!
!
i
¢
[input select ( @linee = mic)]
Microphone Jacks [mic (left@right)]
Record-Muting Button [rec mute (0))
Output Level Control (output level)
(ea he Power Voltage Selector
[DIN] ...* For all European
areas except United Kingdom,
Asia, Latin America, Middle
East and Africa areas.
0
Record Button
{rec- 9 (O)]
Play Button
(play- G(P))
Pause Button
[pause (1)]
Stop Button
[stop (@)]
;
Line Output Jacks (LINE OUT (LeR)]
Line Input Jacks [LINE IN (Le@R)]
—> 2 =—

DISASSEMBLY INSTRUCTION
{
* The head azimuth can be
adjusted by removing the
cassette lid.
Fig. 1
Power supply
Owe (7)
circuit board
Fig. 5
i
Recording-4
(O)
.2(R),— (T) dbx
eet circuit
Se >} board
RS-M228X
(F)
Fig. 4
FL meter unit
(N) Pull out
T
RS-M228X
Fig. 7
Procedure
To remove ——.
Shown in fig. ——.
Case cover
¢ 4 screws
Bottom cover
Front panel
6 screws
Input volume knob-l. assembly ---
Input volume knob-R assembly
1 screw
3 screws
Power supply circuit board
Pull out the connector
28
Cord clamper
Pull out the connection rod (2)
8 red screws
FL meter unit
Pull out the connector
Pull out the FL. meter uni
dbx circuit board
2 red screws and washers
Pull out the dbx circuit board
132—->3-5-6-7
Main circuit board
Cord clamper
Recording wire
Pull out the connector
Pull out 6 connectors
Al, [B
1 ,
7 red screws
1>2>3-+5 8
Mechanism unit
¢ Pull out the counter reset
¢ 4 red screws
¢ Pull out 6 connectors
Al, (Bl, [€
, ’
13 2-35-89
Cassette holder
¢ Cassette {i
* Slide ind

RS-M228X
MEASUREMENT AND ADJUSTMENT METHODS
Tape
selector
(Tape
mode
switching)
(without
dbx
SYSTEM)
For measurement adjustment with test tapes without tape detection
holes switch tape modes as follows.
(For normal tape mode, just insert a normal tape into the cassette
holder.)
: Connection
* Metal tape mode setting: wire
Metal tape mode is obtained by disconnecting the 3 pin socket
from the 3 pin post [B] on the P.C.B. (Printed Circuit Board).
* CrO2 tape mode setting: GROUND
First, disconnect the 3 pin socket [D] in the same way as above.
Then, as illustrated in the figure right, connect the terminal-3 of
the 3 pin post to the ground with a connection wire.
es]
3 pin post-D)
Main P.C.B.
Tape Speed
Adjustment VR VR9 VR6 VR5 VR1 VR2
VR10
ey
elk
/ pee oe
| \
, VR301
a ea ee
a aoe ae
TP5.. >, TP3. “Jumper , TP301
8
A53f
|}
Ra7é
|)
|
x
9R330
‘SL
BEAK
RESET
TERMINAL
\
Fig. 1
NOTES: Keep good condition, set switches and controls in the following positions, unless otherwise specified
@ Make sure heads are clean. @ Input selector: Line
@ Make sure capstan and pressure roller are clean. ® Input level controls: Maximum
@ Judgeable room temperature: 20+5°C (68+9°F) © Output level control: Maximum
@ NR switch: OUT
Screw (A}
® Head position (The head adjusting plate 1s provided to adjust the tape Head Adjusting Plate
adjustment
touch
of
the
head
in
cue
or
review
mode.)
Capstan
Condition 1 Press the playback button and pause button — is
* Playback and pause mode 2 Measure the space between the pressure roller and the Rk
capstan
Standard value: 0.5+0.3mm
Space (adjustable?
If the measured value is not within the standard value,
untighten screw (A), and slide the head adjusting plate
in the direction of arrow (B) for adjustment
Fig. 2
© Head azimuth L-CH/R-CH output balance adjustment a ouT
adjustment 1. Make connections as shown in fig. 3. fossratplavacic est
Condition:
* Playback mode
Playback mode VTIVM Oscilloscope
Fig. 3
i Pressure Roller
ITEM MEASUREMENT & ADJUSTMENT
Equipment 2. Playback the 8kHz signa! from the test tape Record/playback head
*VTVM * Oscilloscope (QZZCFM)
* Test tape (azimuth) Adjust screw (B) in fig. 4 for maximum output L-CH \
+++ QZZCFM and R-CH levels
When the output levels of L-CH and R-CH are not at Screw (B)
maximum at the same time, readjust as follows Fig. 4
3. Turn the screw shown in fig 4 to find angles A and C
(points where peak output levels for left and right channels L-CH peak level
R-CH peak level
are obtained). Then. locate the angle B between angles A
r
and C. .e. a paint where L-CH and R-CH output levels sudan
come together at maximum. (Refer to figs. 4 and 5.) LEVEL
L-CH/R-CH phase adjustment
4. Make connections as shown in fig. 6.
5.
Playback
the
8kHz
signal
from
the
test
tape
(QZZCFM)
—_—
aE?
Adjust
screw
(B)
shown
in
fig.
3
so
that
pointers
of
the
two
A
BC
VTVMs
swing
to
maximum
and
a
waveform
as
illustrated
in
Fig.
5
fig. 6 Is obtained on the oscilloscope
Record/
VIVM
Oscilloscope
playback
head
)VIVM
|
ra
LH
ROS
A
=e
-
revs!) .
1 Eccapee seca Fig. 7
Playback LINE OUT Vertical Horizontal Fig, &
@ Tape speed Tape speed accuracy
Condition 1. Test equipment connection is shown in fig. 8.
+
Playback
mode
2.
Playback
test
tape
(QZZCWAT
3.000H2),
and
supply
Record/playback
head
LINE
OUT
«
Normal
tape
mode
playback
signal
to
frequency
counter
ee
eae
4
Equipment 3. Take measurement at middle section of tape | | oo
4. Measure this frequency. Test tape Playback mode ay Clectric counter
* Digital electronic counter
+ Test tape --- QZZCWAT 5. ha of 3,000HZz, determine value by following Fig. 8
f — 3.000
Af d ae eS 9
ape speed accuracy 3000 * 100 (%)
where, f = measured value
Standard value: +1.5% |
Adjustment method
1. Playback the test tape (middie)
2. Adjust so that frequency becomes 3,000 Hz
3. Tape speed adjustment VR shown in fig. 1
Tape speed fluctuation
Make
measurements
in
same
manner
as
above
(beginning,
middle
and
end
of
tape),
and
determine
the
difference
between
maximum
and
minimum
values
and
calculate
as
follows:
f: —fe
Tape speed fluctuation = ——--— > Y
ape speed fluctuation 3000 * 100 (%)
f: = maximum value, f> = minimum value
Standard value: Less than 1.0%
®
Playback
frequency
Measurement
Playback
frequency
response
chart
response
1.
Test
equipment
connection
is
shown
in
Condition: fig. 3.
*
Playback
mode
2.
Place
UNIT
into
playback
mode
Aer
*
Normal
tape
mode
3.
Playback
the
frequency
response
test
tape
a6
* Output level control «-» MAX (QZZCFM). te
Equipment: 4. Measure output level at 315Hz. 125kHz, | ~2%8 rt
*VTVM — * Oscilloscope BkHz, 4kHz, 1kHz, 250Hz, 125Hz and | ~S8C
+ Test tape --- QZZCFM 63Hz and compare each output level with a - =n
the standard frequency 315Hz, at LINE (io.
OUT.
Fig. 9

RS-M228X
ITEM MEASUREMENT & ADJUSTMENT
5. Make measurement for both channels.
6. Make sure that the measured value is within the range specified in the frequency response chart
(fig. 9).
Playback frequency response adjustment
1. Open or short the circuit's connection points to adjust playback frequency response (see fig. 10).
2. The frequency response when connection points (a) (L-CH) and (a’) (R-CH) are shorted/open
changes as short/open condition at connection points changes as described below (table 1).
Short/open conditions, in turn, differ with sets due to the differences in fine adjustments made prior to
shipping. If readjustments are required, set conditions so that results are as close to the standard
value as possible.
Connection point
(a) (L-CH), (a') (R-CH)
6 kHz 8kHz 10 kHz 12.5kHz
around around around around
Short
+0.2dB}
+04dB)
+08dB)
+12dB
around around around around
ope -~0.2dB] -04dB| —08dB) —1.2dB
Table 1
Connection.“
point (a') /
C7
%390P_ Connection
Record/ point (a)
Playback Head
Connection
point (a)
L-GH)
@ Playback gain _ Test equipment connection is shown in fig. 3.
Condition: . Playback standard recording level portion on test tape (QZZCFM 315 Hz, OdB), and using VTVM
measure the output level at LINE OUT jack.
* Playback mode
Ge, . Make measurement for both channels
* Normal tape mode
Equipment: Standard value: 0.4V+1¢dB
SVM. «« Oselloseope (around 0.42V: at test points TP3 (L-CH) and TP4(R-CH
*
Test
tape
---
QZZCFM
a
:
P
3
ane
a(R
E
i
Adjustment
1. If measured value is not within standard, adjust VR1 (L-CH), VR2 (R-CH) (shown in fig. 1)
2. After adjustment. check “Playback frequency response” again

RS-M228X
ITEM
MEASUREMENT
&
ADJUSTMENT
@ Erase current 1. Test equipment connection is shown in fig. 11.
Condition:
2.
Place
UNIT
into
metal
tape
mode.
Evaga‘head
* Record mode 3. Press the record and pause buttons.
+
Metal
tape
mode
4.
Read
voltage
on
VTVM
and
calculate
erase
current
by
ane
—
Eau
t
following
formula:
Record
mode
aaos
aaIPnEN
Voltage
across
both
ends
of
R125
rare
soya
a
*VTVM
*
Oscilloscope
Erase
current
(A)
=
oo
we
1 (Q) VTIVM Oscilloscope
Standard
value:
155+15mA
(Metal
position)
|
Fig.
11
5. If measured value is not within standard, adjust as follows.
Adjustment
1. Short the points (b) and (c) on the main circuit {
board diagram (see page 25)
2. Make measurement for erase current.
3.
Make
sure
that
the
measured
value
is
within
the
|
:
'
erase
current
of
140mA
to
170mA
oe
|
Open
j
—2dB
|
—1dB
4.
If
measured
value
is
not
within
standard,
short
or
point
(c
;
open
connection
points
(b)
and
(c)
for
adjustment
|
Se
0.108
O08
(see
table
2).
Table
2
_ around 70mA (Normal position)
Reference ‘valle: around 95mA (CrQ2 position)
= 1
Connection point (b) |
Open Short
© Overall frequency Note: | Overall frequency response chart (Normal)
response
Before
measuring
and
adjusting,
make
sure
:
7
Condition:
of
the
playback
frequency
response
(For
*
Record
/playback
mode
the
method
of
measurement,
please
refer
ee
*
Normal
tape
mode
to
the
playback
frequency
response)
a
*
CrO>
tape
mode
Overall
frequency
response
adjustment
ee
*
Metal
tape
mode
by
recording
bias
current
—
408
*
Input
level
controls
---
MAX
s
no
ee
*
Cute
level
control
---
MAX
ieeusdingsequanagnle
wed)
nh
al
eae
ee
Equipments
1.
Make
connections
as
shown
in
fig.
13.
i
QDH2700He
4KHE
5
KHz
|
*v1VM
+
AF
oscillator
2.
Place
UNIT
into
normal
tape
mode
and
Fig.
12
mail
*
Oscilloscope
load
the
test
tape
(QZZCRA).
.
*
Resistor
(6002)
3.
input
a
1kHz,
~24
dB
signal
through
* Test tape LINE IN
(reference blank tape)
Place the set in record mode VR9(L-CH)
- QZZCRA for Norm! 4. Fine adjust the attenuator to obtain Rama dinveack {vanDeRc Pa
* QZZCRX for CrOs 0.4V LINE OUT output head = TART "AP oseilstor
*
QZZCRZ
for
Metal
*
Make
sure
that
the
input
signal
level
33
is —24+4d8 with 0.4V output TPL{L-CH) Piayback7
voltage.
aca
secede
FA
@)
5
Adjust
the
attenuator
to
reduce
the
input
mem
NY
°6)
ro
FLA
a
ering
VIVM_Oseiloscope
6.
Adjust
the
AF
oscillator
to
generate
50
Hz,
oo}
to
100
Hz,
200Hz,
500
Hz,
1kHz,
4kHz,
VTVM
Oscilloscope
For
overall
frequency
;
; ———— response measuremen
8kHz
and
10kHz
signals,
and
record
Far
bag
cuvent
these
signals
on
the
test
tape.
measurement.
7. Playback the signals recorded in step 6, Fig. 13
and check if the frequency response curve
is within the limits shown in the overall
frequency response chart for normal tapes
(tig. 12).
(If the curve is within the charted specifications, proceed to steps 8, 9, 10 and 11,)
If the curve is not within the charted specifications, adjust as follows;

RS-M228X RS-M228X
Adjustment @: Adjustment ®: @ Fluorescent meter . Make connections as.shown (See fig. 17).
When the curve exceeds the overall frequency When the curve falls below the overall frequency Condition: 2. Connect a wire between TP301 and peak reset
response chart specifications (fig. 12) as shown response chart specitications (fig. 12) as shown * Record mode terminal (See fig. 18).
in fig. 14. in fig. 15. * Input level controls --» MAX . In the recording pause mode, apply 1 kHz
+ Output level control --» MAX (—24dB) to LINE IN.
eat _ Adjust ATT so that output level at LINE OUT
Equipment: is O.4V
* VTVM * AF oscillator
«ATT —40dB adjustment
5. Adjust ATT so that the level adjusted at step
4 is reuced by 40dB.
6. At this time, check that — 40 dB indicator is
kHz
2kHz
Wars
SSE
10
kHz
ax
So
10kHZ
lighted
halfway
(intermediate
brightness
3kHz/ /6kH
aki SikHz 71 ‘AC Hi / feu kare between full brightness and light-out: See fig.
19).
Fig. 14 Fig. 15 7. \f the indicator is not lighted halfway as
1)
Increase
bias
current
by
turning
VR9
(L-CH)
1)
Reduce
bias
current
by
turning
VR9
(L-CH))
described
in
step
6,
adjust
VR301.
and VR1G (R-CH). and VR10 (R-CH). OdB adjustment
See fig. 1 on page 5.) 2) Repeat steps 6 and 7 to confirm. i :
2) Repeat steps 6 and 7 to confirm. (Proceed to steps 8, 9, 10 and 11 if the 8 ete ae 4 (set LINE
Proceed to steps 8, 9, 10 and 11 if the curve iS now within the charted specifica- Rion a EN ot lots . . : ;
curve is now within the charted specifica- tions.in fig. 12) . time, ee oe le is lighted halfway (intermediate brightness between full
tions is fig. 12.) 3) If the curve still falls below the charted i iaprone: edie yeaa ig. 20).
if th till h ificati ificati i i : ;
3) e curve still exceeds the specifications specifications (fig. 12), reduce bias current ” Repent adyistmien|e: and chiaciealestene 4 G26: 78) S anal 0 tae Ge tarde tines
fig. 12), i bi t further and furth t re ; ; ,
ee
7
on
aey
aie
Dive
aee
Letras
iene
Disconnect
the
wire
between
TP301
and
ground
terminal,
which
had
been
connected
at
step
2
. Place UNIT into CrO2 tape mode.
ee,
Been
Borne
A
Overall
frequency
response
chart
(CrO2,
Metal)
©
Dolby
NR
circuit
1.
Test
equipment
connection
is
shown
in
fig.
21.
jezdcny
|
Tralee
es
4kH e
kH
ions
a
1D
a
TO
Condition
2. Place
UNIT
into
record mode,
set
the
Dolby
NR
switch
|1C3(R-CH)
2, 2 OINEIES 2 ANG) 9 Bitz HT | Pe a scardaned to OUT position and supply to LINE IN to obtain a
signals.
Then,
playback
the
signals
and
Foner
adie
oa
—34.5¢B
at
PIN
@
[IC2
(L-CH).
C3
(R-CH)]
check
if
the
curve
is
within
the
limits
asi
Z|
‘
aerate
Sie
ie
ae
(frequency
5
kHz}
-
.
shown in the overall frequency response * Input level controls --- f Bak The val IN :
: : t +2.5)dB
chart for CrO2 tapes (fig. 16). it Yt TU Equipment: COON! Weel eee IN Dostonse | ial
Hi aunt greater than the value at OUT position of Dolby NR e
. Place UNIT into metal tape mode change HH or ee ad Ht * VTVM * AF oscillator awiten 5°
test
tape
to
QZZCRZ,
and
record
50Hz,
fligots
$300
Hz
hy
xu
ate
Tt
N72
Sie
*
ATT
*
Oscilloscope
:
100Hz, 200Hz, 500Hz, 1kHz, 4 kHz, uy fa ae \\\g20H| 4kHz NE Rte * Resistor (600 2) Fig. 21 Genin
8kHz, 10kHz and 12.5kHz signals 400 Hz 600 Hz 700 Hz \ §kHz 7kHz
Then, playback the signals and - Fig. 16
check if the curve is within the limits :
shown in the overall frequency response chart for metal tapes (fig. 16).
. Confirm that bias currents are approximately as follows when the UNIT is set at different tape mode.
* Read voltage on VTVM and calculate bias current by following formula:
Value read on VTVM (V)
10 (Q)
Connection
AF
oscillator
ATT
Record
ii
Bias current (A)
Standard value:
around 340 uA (Normal position)
around 440 ZA (CrO2 position) : measured at TP1(L-CH) and TP2 (R-CH)
around 710A (Metal position)
@ Overall gain Test equipment connection is shown in fig. 17.
Condition: 2. Place UNIT into normal tape mode, and load the test Record /playback
* Record/playback mode tape (QZZCRA).
+ Normal tape mode _ Place UNIT into record mode.
* Input level controls --» MAX . Supply 1kHz signa! (—24 dB) from AF oscillator. 2 as
*
Output
level
control
---
MAX
through
ATT
to
LINE
IN.
AF
oscillator
A
Lune
in
Record
mode
* Standard input level; . Adjust ATT until monitor level at LINE OUT becomes
MIC «+++ —72+3¢dB OAV.
LINE IN--» —24+3dB _ Playback recorded tape, and make sure the value at
LINE OUT on VTVM becomes 0.4 V.
_ (f measured value is not 0.4V, adjust VR5 (L-CH),
VR6 (R-CH). Test tape
. Repeat from step (2)
Test tape
Playback head LINE OUT
Equipment:
* VTVM * AF oscillator
* ATT * Oscilloscope
* Resistor (600 2)
+ Test tape
(reference blank tape)
--QZZCRA for Normal
Playback mode “yrym
Oscilloscope
Fig. 17

RS-M228X
MEASUREMENT AND ADJUSTMENT METHODS For dbx SYSTEM)
START
@ Check for
expansion
© Check the voltage at individual
sections of the regulated power supply
circuit in dbx circuit
e Adjustment of regulated power
supply circuit in dbx circuit
@ Repair the power supply circuit section
@ Check for ree ey
expansion
© Check for
standard level of dbx
@ Adjustment of dbx standard level
Repair the control circuit section control
@ Check for
expansion
check of INPUT BAND >>
ASS FILTER (27H2—20kH2)
_Ghack of RMS
FILTER (27H2—10kHz)
_ [ONPAGE13] |
@ Check for
expansion
@ Check the frequency
tesponse of the dbx circuit
TROUBLESHOOTING CHART FOR dbx SYSTEM
Fig. 1
Check the constants of the INPUT
BAND PASS FILTER elements
Check the operation of transistors |
203 and 0204 4
Check the constants of the BAND
PASS FILTER elements
Check the operation of transistors
0221 and 0222
¢ TROUBLESHOOTING CHART FOR dbx SYSTEM
The troubleshooting chart for the dbx system is shown in Fig. 1.
Please follow the sequence of this chart for checking and
repairing the dbx system.
The figures shown in each block indicate the page on which
the checking method, adjustment or measurement is explamed.
Repair the INPUT BAND PASS
Repair the RMS FILTER section
Check the voltages and signal wave
forms at individual sections of the
RMS detector
1
Repair the RMS detector section
Check the voltages at individual
sections of the VCA circuit. Check
the constants of the Pre-emphasis/
De-emphasis circuit elements.
Repair the VCA circuit section or
Pre-emphasis/De-emphasis circuit
Output signal distortion factor
adjustment

RS-M228X
¢ ADJUSTMENT PARTS LOCATION OF dbx SYSTEM
VR204 VR206
(320
1
\ Lo
TP206
f eae
R2508 |;
/
a a
TP204
240
NS
» ae
\
ee
id
., TP207 ~
Tbreos
\
cs
\
press
‘
{press
VR203 VR205
TP205 >,
a apl \
* Pyreas
X nae
cen
7 TP203 ~TP201
Fig. 2
BLOCK DIAGRAM OF dbx
SECTION (L-CH ONLY)
{@P) NIVOWOA
20 wo 500 th Sr 10k 2OKM:
[PRE EMPAHSIS CHARACTARISTIC]
20 100 «500 tk Bh 10k 2OmHe
B00 O
{DE- EMPHASIS CHARACTARISTIC}
100
CONTROL VOLTAGE (mV)
[VCA CHARACTARISTIC]
300 SOO tk Se 10n 20Kne
(BAND PASS FILTER CHARACTARISTIC]
DISe. MODE (DECODE: S1; disc position)
dbx CIRCUIT BOARD
VR201
VCA Symmetry
adjustment VR
Q203
INPUT BAND
PASS FILTER
(27 Hz—20 kHz]
VCA
1€201, 205
L-CH
output
DE EMPHASIS
VR203
RMS detector
adjustment VR
1203
RMS
DETECTOR
VR207
dbx standard level
adjustment VR (Decode)
1C205 Q221
RMS FILTER
(27 Hz—10 kHz)
Q201, 207, 209, 217, 219
205, 213, 215, 211
CONTROL CIRCUIT
Q13, 14, 15, 16
CONTROL CIRCUIT From. St
(NR select switch)
bey
test
‘Tt
HI
2 00 «S00 hk ‘Bk 10K 2OKH2
[RMS WEIGHTING CHARACTARISTIC]
bie
ne mi
=50—40- 30-20-10 0+10+ 20430440450
RMS DETECTOR INPUT LEVEL (dB)
[RMS DETECTOR CHARACTARISTIC]
L 1
20 00 500 tk Ge Ok 2OKHz
IRMS FILTER CHARACTARISTIC]
Note: Encode/decode selection of the dbx circuit in RS-M228X
is done with a control circuit, composed of transistors.
(This control circuit is interlocked with S2 (NR selection
switch).) 13
T T T q T 7 qT [ENCODE OUTPUT CHARACTARISTIC]
te ate
est ttHttte st + Set f
st oetit+ 4444 a a
t +4 CONTROL VOLTAGE (mv)
of itt Hatt |
93 iat Hi (VCA CHARACTARISTIC]
atte + +e
“Trt
3s 10s 20KH2 Cit Lum
20 wo $00 Sex 10k 2OKHE
{BAND PASS FILTER CHARACTARISTIC]
ENCODE MODE\ (RECORD MODE: S1: dbx tape position)
VCA Symmetry
adjustment VR
PRE
EMPHASIS
VR203
RMS detector
adjustment VR
Q203
LOW CUT
FILTER
VR205
dbx standard level
adjustment VR
O1P205|
TP207
1C203
RMS DETECTOR
RMS
WEIGHTING
1C205, Q221
RMS FILTER
Q201, 207, 209, 217
219, 213, 215, 211
CONTROL CIRCUIT
Q13, 14, 15, 16
CONTROL CIRCUIT
From S1
(NR select switch)
+300}
+240]
+180
+120
+60
~60
-120
—180
~ 240
300} -
=50=-40-30-20-1O HO+430440+50
AMS DETECCAR input tevel (dB)
{RMS DETECTORG HARACTARISTIC]
20 7007 BOQ Sm TOK Oks
[RMS WEIGHTING CHARACTARISTIC}
i i
Sk 1k 2OW2
{RMS BAND PASS FILTER CHARACTARISTICI
Fig. 3

RS-M228X
dbx SYSTEM CHECKING METHOD
NOTES: Keep good condition, set switches and controls in the following positions. unless otherwise specified.
@ Input level controls: Maximum
ITEM CHECKING METHOD
@ Check for expansion
Condition:
* Stop mode
* Input level controls --- MAX
* Output level control --- MAX
* Noise reduction selector
--- disc/dbx tape
Equipment:
* VTVM * AF oscillator
* ATT * Oscilloscope
* Resistor (600 22)
® Check for standard
level of dbx
Condition
* Stop/record mode
* Input level controls --- MAX
+ Noise reduction selector
++ disc/dbx tape
Equipment:
* VTVM * AF oscillator
* ATT * Oscilloscope
* Resistor (600)
@ Check the frequency
response of the dbx
circuit
Condition
* Stop/record mode
* Input level controls --- MAX
* Noise reduction selector
-+- disc/dbx tape
Equipment:
* VTVM * AF oscillator
* ATT * Oscilloscope
* Resistor (600)
© Output level control: Maximum
® Check for expansion
1. Make the connections as shown in fig. 4 and
apply 1kHz ~ 27dB signal from LINE IN.
and set the noise reduction selector to disc
LINE IN
LINE OUT
[—*
position
AF
oscillator
Adjust ATT, increase input signal level by 10 dB.
and make sure that the reading for VTVM
increases by 20dB+1dB
ATT ¢
6002
Resistor
i :
Stop/record mode yTVM Oscilloscope
Fig. 4
Adjust ATT, decrease the input signal level. and make sure that the reading for VTVM decreases by
20dB+1dB
@®-1 Check for standard level of dbx in dbx Encode mode
1. Make the connections as shown in fig. 5 and
apply 1kHz —274dB signal from LINE IN.
and set the noise reduction selector to dbx
ape position
2. Set the unit to record mode. adjust At T so
that the signal level at TP201 (L-CH) and
TP202 (R-CH) is 300 mV
3. Make sure that the signal level at TP203 (L-CH)
and TP204 (R-CH) is 300mV+0.5dB
AF oscillator
TP201 (L-CH)
VTVM_ Oscilloscope
TP203(L-CH) |=
TP204(R-CH)}! _/
TP202(R-CH) ©
ATT
600
@-2 Check for standard level of dbx in dbx Decode mode
1. Make the connections as shown in fig. 5 and apply 1 kHz —27dB signal from LINE IN. and check as
follows:
TP207-4..[
Record mode
Resistor
LINE IN
dbx circuit board
Fig. 5
2. Set the noise reduction selector to disc position and adjust ATT so that the signal level at TP201
(L-CH) and TP202 (R-CH) becomes 300 mV
3. Make sure that the signal level at TP203 (L-CH) and TP204 (R-CH) is 300mV+0.5dB
@-1 Check the frequency response during decoding
1. Make the connections as shown in fig. 5 and apply 1 kHz
— 27 dB signal from LINE IN, and check as follows:
2. Set the noise reduction selector to disc position, and adjust
ATT so that te signal level at TP201 (L-CH) and TP202
(R-CH) becomes 300 mV.
3. With the signal level at TP203 (L-CH) and TP204 (R-CH)
as OdB. change the signal frequency to 1OOHz, 20Hz and
7 kHz respectively. Read signal levels at TP203 (L-CH)
and TP204 (R-CH) and check that they are within the
specifications-1
@-2 Check the frequency response during encoding
1. Make the connections as shown in fig. 5 and apply 1 kHz
— 27dB signal from LINE IN. and check as follows:
2. Set the noise reduction selector to dbx tape position. and
the unit to record mode
3. Adjust ATT so that the signal level at TP201 (L-CH) and
TP202 (R-CH) is 300 mV :
4. With the signal level at TP203 (L-CH) and TP204 (R-CH)
as OdB, change the signal frequency to 1OQHz and 7 kHz
respectively. Read signal levels at TP203 (L-CH) and
TP204 (R-CH) and check that they are within the
specitications- 2.
Specifications-1
| Frequency
Signal levels at
TP2023 and TP204
1 kHz
0.dB (300 mV)
100
Hz —0.5dB* 1dB
20Hz
—30dB+5dB
7 kHz
+7dB+1dB
Specifications-2
Frequency
Signa! levels at
TP203 and TP204
1k Z 0 dB (300 mV)
100
Hz +0.5dB+1dB
7k
z ~ 3.5dB+1dB
NOTES:
e If the results of the above checks @. © and @ do not satisty the specifications, perform the following adjustments
If the specifications are not satisfied even after the adjustments, follow the checking procedure for problems.
¢ lf the output signal is not produced or is extremely distorted, follow the checking procedure for problems

ADJUSTMENT OF dbx SYSTEM
NOTES:
When
adjusting
the
circuit
of
the
dbx
system,
be
sure
to
perform
the
adjustments
in
the
following
order:
@ Adjustment of
Keep good condition,
RMS
detector,
@
Adjustment
of
VCA.
@
Adjustment
of
dbx
standard
level.
set
switches
and
controls
in
the
following
positions,
unless
otherwise
specified.
@ Input level controls: Maximum
ITEM
ADJUSTMENT
@ Adjustment of RMS
detector
Condition:
+ Stop mode
* Input level controls --- MAX
» Noise reduction selector
+++ disc
Equipment:
* VIVM * AF oscillator
* ATT * Oscilloscope
* Resistor (600 Q)
— VTVM 0
1.
Make
the
connections
as
shown
in
fig.
6,
and
a
eee
set the noise reduction selector to disc position
TP201 (L-CH) dbx circuit board
TP202 (R-CH) /
2. Apply 1OOHz -— 27dB signal from LINE IN. TP207 (Earth) | ;
3. Adjust ATT so that the signal level at TP201 et. Eevee
CH) (L-CH)
(L-CH) and TP202 (R-CH) becomes 300 mV ecal y TP207 (R-CH)
4. Make sure that the output signal at TP205 = =
disc ‘
Lween
(L-CH) and TP206 (R-CH) is at 200H2 sine
wave LINE IN
If the output signal is not sinusoidal as shown
in fig. 7, adjust VR203 (L-CH) and VR204
(R-CH) to make it sinusoidal
NOTE:
The voltage of the output signal after adjustment
is about 0.5mV rms
Wave form before adjustment Wave form after adjustment
(sine wave)
Fig. 7
@ Adjustment of VCA
Condition
* Record stop mode
* Input level controls --- MAX
* Noise reduction selector
-+ disc ‘dbx tape
Equipment:
* VTVM * Oscilloscope
* Resistor (1008. 3.9)
Preparation before adjustment
1. Before adjusting VCA, from the device shown below using resistors of
100 and 3.922 (See fig. 8)
Set NR switch to dbx disc
Remove jumpers [J2 (L-CH) and J20 (R-CH)]}.
3. Arrange connections referring to wire connection diagram (fig. 9 and 10),
since OV. + 180mV and — 180mV (DC) are applied in this order to pin
2 of IC201 (L-CH) and pin 2 of IC202 (R-CH).
1C201(L-CH)}
1202 (R-CH){ dbx circuit board
2
1C201 (L-CH)
__1€202(R-CH)
9 Clee
DC power supply
TP203 (L-CH)|
Oscilloscope
dbx circuit board
DC power supply 1P207
1P203(L-CH) V/ cam =
TP204 (R-CH) disc position
TP204(R-CH)f
\
disc position
Osilloscope
Connections
when
applying
+
180mV
Connections
when
applying
—180mV
and OV
Adjust DC power supply and arrange connections
so that 4+ 180mV or OV can be applied to
TP203 (L-CH) and TP204 (R-CH)
Fig. 9
Adjust DC power supply and arrange conrecti ons
so that - 180 mV can be applied to TP2)3
(L-CH) and TP204 (R-CH)
Fig. 10
Adjustment procedure
1.
Apply
OV
to
pin
(@
of
{C201
(L-CH)
and
pin
2
of
1C202
(R-CH).
and
a
horizontal
line
will
aprear
on
the
screen
of
the
oscilloscope.
Use
this
line
as
the
reference
line
2
Apply
+180
mV
to
pin
2:
of
IC201
(L.CH)
and
pin
(2;
of
C202
(R-CH)
(See
fig.
9),
and
chek
that
the
level
is
not
more
than
10mV
from
the
reference
line.
If
improper,
adjust
VR201
(L-CH)
ad
VR202
(R-CH).
In
the
same
way,
apply
~
180mV
to
pin
(2,
of
IC201
(L-CH)
and
pin
@
of
IC203
(R-CH)
(Se
fig.
10).
and
check
that
the
level
is
not
more
than
10
mV
from
the
reference
line.
If
improper.
adjust
VR201
(L-CH)
and
VR202
(R-CH).
_ Repeat steps 2 and 3, and adjust VRs so that
the levels are within + 10mV when + 180 mV
and —180mvV are applied (fig. 11).
After adjustment, connect jumpers J2 (L-CH)
and J20 (R-CH) (See fig. 2).
+10mv :
—10mv — When OV is applied to pin 2. o f IC201
(L-CH) and pin <2. of IC20;(R-C H),
this horizontal line appear:
Oscilloscope screen
Fig. 11
® Adjustment of dbx
standard level
Condition
* Record/stop mode
* Input level controls --- MAX
NOTE:
Be sure to perform the standard level adjustment in dbx Encode, followed by the standard level ajus t-
ment in dbx Decode

RS-M228X
* Noise reduction selector
+++ disc ‘dbx tape
Equipment:
*VTVM * AF oscillator
* ATT * Oscilloscope
* Resistor (600 £2)
@-1 Standard level adjustment in dbx Encode mode
1. Make the connection as shown in fig. 12 and
apply 1kHz —274dB signal from LINE IN. and
set the noise reduction selector to dbx tape
position
Set unit to record mode, adjust ATT so that
the signal level at TP201 (L-CH) and TP202
(R-CH) is 300 mV
Adjust VR205 (L-CH) and VR206 (R-CH) so
that the output signal level at TP203 (L-CH)
and TP204 (R-CH) becomes 300 mV +0.5dB.
dbx circuit board
TP201(L-CH) |
TP202 (R-CH)
TP207 +
Record mode f rye
J
{
tp
1
ITEM ADJUSTMENT
Ps
Tp20siL-cH)
TP204(R-CH)_
VTVM_ Oscilloscope
rsa
JUNE INU | i
600.2 “VR207(L-CHT oo
Resistor { vez08(R-CH) VTVM Oscilloscope
. R205 (L-CH)
Fig. 12 —vR206(R-CH)
@-2 Standard level adjustment in dbx Decode mode
]
2
3
Make the connection as shown in fig. 12 and apply 1 kHz —27 dB signal from LINE IN, and perform
the following adjustments
Set the noise reduction selector to disc position, and adjust ATT so that the signal level at TP201
(L-CH) and TP202 (R-CH) becomes 300 mV
Adjust VR207 (L-CH) and VR208 (R-CH) so that the output signal level at TP203 (L-CH) and
NOTES:
© After adjustments @. @ and @. re-check according to “dbx SYSTEM CHECKING METHOD"
e if the specifications are not satisfied, perform the adjustments again.
TP204 (R-CH) becomes 300mV+0.5dB
CHECKING PROCEDURE FOR PROBLEMS
NOTES: Find defective parts according to the circuit operation checking method given below, and use the results for your reference
during repair. Remember to adjust after repair
Keep good condition, set switches and controls in the following positions, unless otherwise specified
@ Input level controls: Maximum
BB Operation check of
regulated power supply
circuit in dbx circuit
Equipment :
* DC volt meter
* Oscilloscope
G@-1 Check of +10.5V voltage
Make the connection as shown in fig. 13 and
make sure that tne emitter voltage of Q26
is around + 10.5V
OC volt meter
DC volt meter
ITEM CHECKING METHOD
GB-2 Check of —10.5V voltage
Make the connection as shown in
fig. 13 and
make sure that the emitter voltage of Q27
is around — 10.5V
i 029 44
164470
cl2e
16¥i000

Check of control
circuit in dbx circuit
Equipment
* DC volt meter
NOTE:
RS-M228X
CHECKING METHOD
E.C.B (G.S.D) voltage check of each switching transistor for Encode/Decode
The terminal voltage of each switching transistor in Encode/Decode mode are shown in the table below
Decode (dbx tape)
C (S) B (D)
OV OV
OV OV
Encode (dbx tape)
eE@ | co | 80 [| €@ |
—01V [| ov ov —0.03V
~0.08V ov ov ov
-0.22V | 10.53V —0.19V
—051V | 10.52V -0.5V
—o.0av | —0.22v | —0.19V
0.01v. | —0.51V —0.46V
=0.22V | -0.22V | ov
—05V | —05V | ov
ov Ov
ov ov
—0.16V ov
—0.15V ov
ov —0.16V
ov —0.15V
—0.16v | —0.16V
—0.15V | —0.15V
|
|
Transistor
Ref. No.
Q201
Q202
Q203
Q204
Q205
Q206
Q207
Q208
Q209
Q2
Q2
Q2
Q2
Q2
Q2
Q2
Q2
Q2
Q2
OV —0.08V
OV 0.01V
—9.08V | —0.08V
—10.64V | —0.33V
—1.53V 10.52V
OlLOINI Dm! R]Wlrmo]e fo
© If no abnormality is found in steps J and @2 check the operation for each part as follows:
Operation check of
INPUT BAND PASS
FILTER circuit
(27 Hz— 20 kHz)
Condition
* Record mode
* Input level controls --- MAX
* Noise reduction selector
+ dbx tape
Equipment:
*VTVM * AF oscillator
* ATT * Oscilloscope
* Resistor (600 2)
Operation check of
VCA circuit and
Pre-emphasis/
De-emphasis circuit
Condition:
* Stop/record mode
* Input level controls --- MAX
* Noise reduction selector
-- disc/dbx tape
Equipment:
*VTVM * AF oscillator
* ATT + Oscilloscope
* Resistor (600 2)
1. Make the connections as shown in fig. 14, and
apply 100Hz — 274dB signal from LINE IN, and
set the noise reduction selector to dbx tape
position
Set the unit to record mode
Adjust ATT so that the signal level at TP201
L-CH) and TP202 (R-CH) is 300 mV.
ake sure that the emitter signal level of Q203
L-CH) and Q204 (R-CH) is 300 mV
Set the input signal frequency to 5kHz and
make sure that the emitter signal of Q203
L-CH) and Q204 (R-CH) remains at the same
evel (300 mV).
4 Q203 (L-CH)
TP203{(L-CH)
)
dbx
circuit
boar
204
(R-CH)
— TP204{R-CH) J “VTVM Osslloscope
_— ae
> STPOOOO] F |
ae
A
AF
oscillator
AT
=
6002/
ae
esistor, ait ere
LINE IN dbx circuit toard
VTVM_ Oscilloscope
Fig. 14
GJ-1 Operation check of VCA circuit and Pre-emphasis circuit
1. Make the connections as shown in fig. 15, and
apply 1OOHz —27dB signal from LINE IN.
2. Short pin @ of IC201 (L-CH) and IC202
(R-CH) to TP207 (ground) as shown in fig.
16
3. Set the unit to record mode, and set the noise
reduction selector to dbx tape position.
4. Adjust ATT so that the signal level at TP201
(L-CH) and TP202 (R-CH) is 300 mV.
5. Make sure that the output signals at TP203
(L-CH) and TP204 (R-CH) are sinusoidal.
(The operation of VCA can then be checked.)
6. Shift the frequency of input signal to 5kHz, and make sure that
the output signal levels at TP203 (L-CH) and TP204 (R-CH)
are increased by about 12 dB.
(The operation of the Pre-emphasis circuit can then be checked.)
TP203 (L-CH)
TP204(R-CH) VIVM Oscibsco pe
TP201 (L-CH) |
1P202(R-CH)
LINE IN
ATT
Resistor
AF oscillator
VTVM Oscilloscope
Fig. 15
10201 (1 -CH)
1€202(R-CH)

RS-M228X
ITEM CHECKING METHOD
@§-2 Operation check of VCA circuit and De-emphasis circuit
1. The procedure is the same as 1 for the above GB-1 VCA circuit
and Pre-emphasis circuit 1201 (L-CH)
2. Short pin @, of IC201 (L-CH) and IC202 (R-CH) to TP207 aaa
(ground) as shown in fig. 17.
3. Set the noise reduction selector to disc position
4. Adjust ATT so that the signal level at TP201 (L-CH) and TP202
(R-CH) is 300 mV.
5. Make sure that the output signals at TP203 (L-CH) and TP204
(R-CH) are sinusoidal. Fig. 17
(The operation of VCA can then be checked.)
6. Change the frequency of input signal to 5kHz and make sure that the output signal level at TP203
(L-CH) and TP204 (R-CH) is decreased by about 12 dB.
(The operation of the De-emphasis circuit can then be checked.)
Connection wire
Operation check of 1. Make the connections as shown in fig. 18. and TP2OLL-CH) 991 «L-cH)
RMS FILTER circuit apply 1OOHz — 27dB signal from LINE IN TP2O2IR-CHY 999 (RCH
(27
Hz—10kHz)
2.
Set
the
noise
reduction
selector
to
disc
position
“VIM
Ose
Condition: 3. Adjust ATT so that the signal level at TP201 TR] Le;
(L-CH) and TP202 (R-CH) is 300 mV
4. Make sure that the emitter signal level of Q221 AF oscillator ak tes
(L-CH) and Q222 (R-CH) is around 300 mV LINE IN
5. Change the frequency of input signal to 5kHz
illoscope
* Stop mode
* Input level controls --- MAX
* Noise reduction selector
+ disc
Equi i and make sure that the emitter signal of Q221
eee
(L-CH)
and
Q222
(R-CH)
remains
at
the
same
VIVM
Oscilloscope
* VTVM * AF oscillator level (300 mV)
* ATT * Oscilloscope Fig. 18
* Resistor (600 Q)
ELECTRICAL PARTS LOCATION
E19 E16

RS-M228X
NOTES:
...For all European areas except United 2 rrr a;
ol Kingdom. ‘ I Q27 Ee
...For United Kingdom.
[N] ...For Asia, Latin America, Middle
East and Africa areas.
[A] ...For Australia.
\
_
uy
/
4S
E13
A
|
Flom.
1
£6
£E8
va
|
|
Fi—
/
fe
rate
Fuse
/
pel
\UL
[
§-E26
|
E7.
qo
|
REPLACEMENT PARTS LIST
Important safety notice
Components identified by A mark have special
characteristics important for safety.
When replacing any of these components, use
only manufacturer's specified parts.
Ref No. [ Part No. Ref No.
| Part No.
Part Name & Description Ref No.
Part Name & Description Part No. Part Name & Description
E 18 QKJM0084 Meter Holder
E19 XTN3 + 10B Tapping Screw @3x 10
E 20 QJS1924TNL = 12 Pin Socket (L-Type)
ELECTRICAL PARTS [B] A QFC2105M AC Power Cord
[For United Kingdom.]
[AJA QFC1208M AC Power Cord
[For Australia]
1 QWY4122Z Head (for
Record/Playback)
QWY2138Z Head (for Erase) [IN] A RJA52ZB-K AC Power Cord E21 QMLM0043 Reset Lever
[For Asia, Latin America, Middle East and Africa E 22
QJS1921TN 3 Pin Socket areas.] [DBA] RHR993Z Cord Clamper
QJP1921TN 3 Pin Post
10 QJP1924TN 12 pin Post
QJP1922TN 6 Pin Post
SJT777
E
E2
E3 QJT1054 Contact
E4
E5 [For all European areas and Australia.]
E
mim
oO
Pin Terminal E2
3
[DN] QKJM0083 Switch Cover (for S10)
[DB] A QTF1054 Fuse Holder QJT0053 Pin Terminal [For all European areas, except United Kingdom,
{For all European areas.]} QTHMO0016 Heat Sink Asia, Latin America, Middle East and Afriaca
[IN] A QTF1007 Fuse Holder QTSMO0069 Shield Plate (2) areas.]
E 24 QJS1922TN 6 Pin Socket
E 25 QJS1923TN 9 Pin Socket
E 26 QZE0003 Porcelain Tube
[For Asia, Latin America, Middle East and Africa
areas.]
E 8[DJA SJA88 AC Power Cord
[For all European areas except United Kingdom.]
XTN3 + 8B Tapping Screw @3x8
QSIFLOO7F FL Meter
QTSMO0070 Shield Plate (for FL Meter)
QJP1923TN 9 Pin Post
mmmmmmm hk eh ok kk NOORWNA
RS-M228X
BLOCK DIAGRAM
J4 LINE IN
O— 4
$1-7 $3-1 $3-3 $1-8
19 ] 20 [21 1 [2 ]3 7 J8 [9 22 123 [24
MIC
IN
J1
O
9
9
O
Oo
O
O
VR3 INPUT LEVEL
CONTROL
Q3
FF/REW
VR1 PLAYBACK GAIN
ADJUSTMENT VR
Q9 FF/REW
MUTING
CONTROL
VRQ BIAS CURRENT
Cc }2
ADJUSTMENT VR ey OO O
Normal CrO, Metal
\e5 Be CR 3,
‘®@ ¥) yy) i5— NETWORK E
(REC EQ)
VR5 RECORDING GAIN
ADJUSTMENT VR
LED4
ICB (AN6256) $6 (Metal)
AUTO TAPE
SELECTOR 1C5
| Y S7 (Normal/CrO,)
ERASE
HEAD
el
("
ze
a
Gres
|
om
REC
MUTE
NA,
r,
Q23~Q25
OSCILLATOR
@,
eo,
BIAS
S9
ite
CONTROLLER
Sie
peta
CONTROL
F4
m1
240V
O
TO FL METER
(FILAMENT)
B+
Q27 Voltage B-
Regulator
D30~D33
RECTIFIER
MAIN CIRCUIT/dbx
CIRCUIT/BIAS
OSCILLATOR
AC IN
Q26 Voltage D34~D37
Regulator RECTIFIER

RS-M228X RS-M228X
[AALAND MM 7
ALA LYMM
mii itil
WITT iia
Name & Description
r Holder
ing Screw @3x 10
n Socket (L-Type)
t Lever
Clamper
Australia.]
h Cover (for S10)
pt United Kingdom,
East and Afriaca
Socket
Socket
ain Tube
BLOCK DIAGRAM
J4 LINE IN
$1-7 $3-1 $3-3 $1-8
19 20 f21 1 [2 ]3 7 {8 Jo
MIC IN J1 Oo Ff F O oO °
VR3 INPUT LEVEL
CONTROL
VR1 PLAYBACK GAIN
ADJUSTMENT VR
CR NETWORK
oy
VRQ BIAS CURRENT (a
1 Ic j2
ADJUSTMENT VR an 77 O O O
Normal CrO, Metal
wh wb al as
q y) yy) 5 NETWORK | =
1C6 (AN6256)
AUTO TAPE
(REC EQ)
S6 (Metal)
SELECTOR
| Y S7 (Normal/CrO,)
ERASE
HEAD
ees
x
¥
L7,
Q20
|
A
OSCILLATOR
K
}
eo,
BIAS
CONTROLLER
F4 11
TO FL METER
(FILAMENT)
Q27 Voltage
Regulator
D30~D33
RECTIFIER
MAIN CIRCUIT/dbx
CIRCUIT/BIAS
OSCILLATOR
Q26 Voltage
Regulator
D34~D37
RECTIFIER
DECODE ENCODE
(@-5
OUT
OB+
B+
Q3
FF/REW
Q9 FF/REW
MUTING
CONTROL
1C303 (AN6870N)
FL METER DRIVER
1C301 (BA6138)
Logarithmic
Compression AMP
G7)
VR5 RECORDING GAIN
ADJUSTMENT VR
10302 (AN6552)
OP AMP
Q301~Q303
METER MUTE & PEAK RESET
VR7 OUTPUT
cs
LEVEL
CONTROL
sc
=—_ (5)
(Pr (4) 4
REC MUTE \Q, (6) many,
23~-Q25 2
es
Q23~Q
P
on1
J3
HEADPHONES
ae aia 1@ LINE MUTE L
CONTROL Roh
240V
O
NOTES:
© $1-1—S1-14...... Record/playback select switch (Shown in playback
position).
© $2-1—S2-8 ...... NR select switch (shown in DOLBY IN position).
(®...Dolby IN, @...Dolby OUT, @)...dbx Tape,
@...dbx Disc).
© $3-1—S3-4 ...... Input select switch (shown in LINE position).
© S4 ened as .Rec Mute ON/OFF switch (shown in OFF position).
.Power ON/OFF switch (shown in ON position).
@:S6.S7 soa: Auto tape select switch.
Paee Cn
Normal Tape
Fon |
[e.tare [on [OFF |
©1983 fies wicca mesma: Fast wind ON/OFF switch (shown in ON position).
-Play muting ON/OFF switch (shown in ON position).
S10 as sisast AC power voltage select switch.
* ( <> ) this arrow indicates the flow of the playback signal.
¢ ( mi ) this arrow indicates the flow of the recording signal.
AC IN ° ( Gm ) this arrow indicates the flow of the playback and recording signal |
in combination.

RS-M228X RS-M228X |
5
SCHEMATIC DIAGRAM
f
t
a13 a14—16
Hy main section pai, a2 Q1,3 D17 D411, 12 D13, 14 D39, 40 D15, 16 ,
i
ica
2SC945(P,K)
1c2
73177
2SA999(E.F)
182473177
2SC945(P.K)_—
ss2473T77
18247377
C4,
&
RD20EB3T M5219L] t 182473177 B+ 10.57V 1824 or 2SB641(R,S or 2SD636(R,S) IM5218L]
; A [RD20E83} t ] terranes [MA161] INE646N} [MA161] pspeant ) [MA161] [28c945-0] [MA161} [MA161] ‘ IC7 M5230L
i f R80 100K _—
i el a See
® -10.5V
[| —_}____—~%
Ty, fg OUT | to FL METER
S1-6
SI-7
S1-8
ee
SECTION
|
@ REC MUTE
> DDE ® ac3v
’ ® ¢ Poe q) acay
LINE IN a hal o
J4 LCH GO =
16V10 27K
© .
eto an
J5 RCH GY@ =n
. R2_ 470K
RS
4 |
B S31 $33
OO@ oo 0)
LJ || ‘
1 a
CRI
MIC IN eS
| :
J1 (L-CH) t bd!
@
@ '
© ton |
. 6) o . .(
® ary ‘
J2 (R-CH) _$3-2 $3-4
, it
: Di Fi as D38
OOOOGP 182473177 25C965(0,R) nan ae shear | $8100 192473777
. aol gas
Ue Sa |W ec 2scats(P.K) IMArstL Eecerel 1 [ahah Pee] Paton
C
.
eae
i
[NE646N)
‘Pak
ah
p-—------
a
D28
ana
@
RUZ
j
\
-
g
182473LF
sont]
18
alt
,
;
RCH
[MA161]
1838V"
g
——
au
:
RIP HEAD 30 2SD965(Q,R) :
(Qwy4122z) —? H : [2SD965] se eee ty
pu
ee
be
=
PHONES
TACK
TT
TT
h as C3 as—s
S300
alt
i
2SK104H
SECTION
|
yo
|
.
[28K104]
|
656
:
np
Hean
|_
til
se
4r
ag
a19
t
=
100KF
25A999E,
F)
r { == ‘ or 2SBE41R,S) ogg
Z 4 Rt \ és [2SB641} arceeet NPE ese 7
* | i ag IC6 ANG
IP C54 $ 6 = UT ‘
. » ' A tt t+
; vR6 7 4 : | .
+ -19 . 0 h 4 4 i
4
y
c7g
t
x
|
& = F - J.
: 1 |
D a aed d oa Ny L BOREL
. > é c if .
Q10 952 F
2SC965(Q,R) 150K
[2SC965Q]
2SD965(Q,R) 182473177 et
)
MA
161
70.330
; Connection Point (a) 2SC945(Q,K) [2SD965] it 61) WA-
or 2SD636(R,S) 182473177
__CRI2 [28C945-Q) uae siees (MA161] .
WV
A Q18 R121 100K
ZSA99KE,F)
R120 : lor 2SB641(R,S)
47K
4
21
[2SB641]
YRe. $ sd net ADBAZEB2LF
a Fait at
‘cay SOK! ‘onnection Point (c) Ps | D20 [SVDRD82EB]
SOKIB) 134, 560 R138. 10K | DIS si-i4 482473177 | p20 | a
MA161]
4 sci cf D21, 22 t -1037V i
E Se0P J 182473177 [A 10.250 z baa _—!
[MA 161] 1666
iW D19 ‘ .
©
ure
:
.
3
IMA161 ig * Pe
l
16V%5
p
1
A
At
ERASD HEAD 470 T400mA
@ Q23, 24
(QYw21382)
6
4 mgs PPSDeanS) aay 030-33
Q, 1 or f O~_0-~G)
x > @ [28C945-Q] A156 5.6K moos A,
R125 C105 33K ©)—<6)
1
0.015
$
Al
{ 0124 &
LY 16¥1000 |~
i
Connection
Point
(b)
|
x
ube
mS
cua
mie
es
Q20 Q21, 22 Riad RIGS I 16v470
i . 4s D25, 26
' 2SD592NCS 2SA999(E,F) 127 680 Q25
: [2SD592] [2SA999] ae) r 152473 MS24TaTTT ube 2SA999(E,F)
b—d--b—d . & [MA161] [MA161] _ 1SR35200LF gy ogagaiiR,)
‘ ———— . . 3 & & ¢ . - e . O=—O—=GB) [SM112] [2SB641] (5)
;
023,
24
]
.
:
ice
Bl
oo
|
a
ae
é ‘
es
:
: 1824731775 1ED2_ LeD3 LEDS J * [AN6256] of - 3 = oe @ © POWER SUPPLY {(D * For all European areas {M * For Asia, Latin America, Middle East and Africa areas.
i
F
[MA161]
a
-
Sé s7
s
s
Q26 O27
\c7
SECTION
United
Kingd
SECTION (Metal) (Cr02) (FF/REW) (MUTING) 2801847(Q,R) 2SA886(Q,R) (M5230L] (M) except United Kingdom
.
$
7
{28C1847Q]
[2SA886Q]
MOTOR
LED1, 3 LED2 LED4 (0xu0297)
[LN216RP] [LN316GP] [LN416YP]
(RED) (GREEN) (YELLOW)
aS
ee

a .
O13 D13, 14
D11, 12
7. 2SA999(E,F)
B+
10.57V
182473777
or
2SB641(R,S)
182473177
[MA161] [2SB641] [MA161)
Q14—16
D39, 40 D15, 16
2SC945(P.K) 452473177: 1$2473T77 \c4, 5
or 280636(R,S) ‘aver TMAtBt] [M5281]
[2SC945-Qj
1O57y
isan es R101
Vee disctHy 1 58K _ig 29y
1 {-10.30v)
DECODE {H)
1
ENCODE (Hi
1
dbx Block
ING our
54
room -- 5
----4
M.P.X1
0-9
[= 3] Pa
7P
(45 vO
R51 R53
150K ARS
7 +4)
6 23k
| c= |:
|
a3 i
PSCC 0.R o0lv g.0ay 5 tay 12K
: ! Legh sgsh | [MA161]
$2-4 Lt AW. a D yr +
See = = p28 RUS 4.7K \ é)
DdoO fF 182473LF saat] O18 ok tose
ROH [MA161] 838)
Qi
2SD965(Q,R)
[2SD965)]
Qs5—8
2SK104H
[2sk104] | 036,
4
Q10 852
2SC965(Q,R) 150K
[2SC965Q]
Qi9
2SA999(E,F)
or 2SB641(R,S)
[2SB641]
100k
~O2v
MUTING ON
0,68V
in
p38
[fs
ROS
TOK
37100
192473177
+10.5V
-10.5V
J
LCH OUT
GND to FL METER
RCH OUT SECTION
REC MUTE
AC3V
AC3V
Ars nA
~O-
T400mA
ropean areas IN * For Asia, Latin America, Middle East and Africa areas.
182473177 80
{2SD965]
[MA161]
1500P’
a
p29
AW
Tats RD8R2EB2LF
Pagel $2-7 20 ISVDRD82EB]
|. p19 Si-i4 182473177 | 20 7
21, 22 DOOOO ais7 330 [MA161] oa
182473177 @® @
mas ar
p19 cio denis 1536V
192473177 var 0K ee
[MA161]
(22V Q24 1K
Q23, 24 (0.26)
2SC945(P,K) KB
or 2SD636(R,S)
J [2SC945-Q] Cy)
= Oi | ay
7 Bi ae
4 RISB Ar2
—— ar
p45 D25, 26 OD @
182473
182473177
D27
aS
AGeaE
5
Yr
rae
.
[MA161} IMA161] 1SR35200LF H A
: d b—O—— « 1SM112]} °F 2SB641(R,S) b+ 400mA
SO
(
ii
maleic.
at
is
aS:
-
:
o—o
Dj
rower
suppty
*
For
all
Eu
a
89
26
a27
1¢7
SECTION
ited
Ki
(cro2)
(FF/REW)
(MUTING)
2801847(Q,R)
2SA886(Q,R)
[452301]
(M)
except
United
Kingdom
[2818470] [2SA886Q] MOTOR
(axuo297)
EQUIVALENT CIRCUIT
| t
AACIN
[A] * For Australia.
NOTES:
¢ $1-1—S1-14...... Record/playback select switch (shown in playback
position).
° $2-1—S2-8 ...... NR select switch (shown in DOLBY IN position).
(@®...Dolby IN, @)...Dolby OUT, @)...dbx Tape,
@...dbx Disc).
© $3-1—S3-4 ...... Input select switch (shown in LINE position).
e $4... ..Rec Mute ON/OFF switch (shown in OFF position).
¢ S5.. ..Power ON/OFF switch (shown in ON position).
¢ $6,S7 ... ..Auto tape select switch.
[= ya
Tomaitane | on | on
[co.tene | on | OFF
[wasps | oFF | oFF |
© SB eee ieietge dee Fast wind ON/OFF switch (shown in ON position).
.-Play muting ON/OFF switch (shown in ON position).
° $10 .. [BIN]: AC power voltage select switch.
» For all European areas except United Kingdom,
Asia, Latin America, Middie East and Africa areas.
eVR1,2. .Playback gain adjustment VR.
e VR3,4. .Input level controls.
e VR5,6. -Recording gain adjustment VR.
© VR7,8 . -Output level controls.
e VR9,10_ ... -Bias current adjustment VR.
¢ Connection points (a), (a’)...For playback frequency response adjustment
points.
* Connection points (b), (c) ...For erase current adjustment points.
Resistance are in ohms (&), 1/4 watt unless specified otherwise.
K = 1,0002, M = 1,000K.
Capacity are in microfarads (uF) unless specified otherwise.
P = Pico-farads.
The mark (¥) shows test point. e.g. V=Test point 1.
. indicates the flow of the playback signal (dbx out).
o( ) indicates the flow of the playback signal (dbx tape).
a | indicates the flow of the recording signal (dbx out).
(a ) indicates the flow of the recording signal (dbx tape).
e
Important safety notice
Components identified by A mark have special characteristics important
for safety. When replacing any of these components, use only
manufacturer’s specified parts.
¢ All voltage values shown in circuitry are under no signal condition.
Uniess otherwise specified, voltage measurement conditions are that tape
travels is at REC, tape mode at METAL, and NR switch at OFF.
( y,) Misageteeds Voltage at playback mode.
DOLBY IN .... Voltage value at IN (NR select switch) mode.
DISC .Voltage value at DISC (NR select switch) mode.
FF/REW ... -Voltage value at FF/REW mode.
MUTINGON ...... Voltage value at muting ON mode.
¢ Described in the schematic diagram are two types of numbers; the supply
parts number and production parts number for transistors and diodes.
One type of number is used for supply parts number and production parts
number when they are idential.
eg. Q1
2SB745(TMG, UMG)<—Production parts number
[2SB745T] «Supply parts number
D1
QVID1S2473T «—— Production parts number
jaaael + Supply parts number
¢ The supply parts number is described alone in the replacement parts list.
¢ This schematic diagram may be modified at any time
with the development of new technology.
* Output level control --- MAX.
SPECIFICATIONS — «* Input level controls --- MAX.
Playback S/N ratio Greater than 45 dB
* Test tape --- QZZCFM (without NAB filter)
Overall distortion Less than 3%
* Test tape
«++ QZZCRA for Normal
vo azzCRK forgroas Lessig .0 7.
-- QZZCRZ for Metal (CrOz, Metal)
(Normal)
Overall S/N ratio
* Test tape --- QZZCRA
Greater than 43 dB

12 u
CIRCUIT BOARDS
CONNECTOR [B+ 10.57v |
[B+ 683v_] [ B- 6.81V
B- 10.53V
1_| REC SIGNAL OUT (R-CH)
2_| GROUND
3 | PLAY SIGNAL IN (R-CH)
=
Connection Point (a)
Connection Point (a’)
CONNECTOR
1 | SIGNAL IN (R-CH)
GROUND
SIGNAL OUT (R-CH)
B- (bias) -10.64V
SIGNAL OUT (L-CH)
B+ (bias) 10.53V
SIGNAL IN (L-CH)
ENCODE (H)
DECODE (H)
DISC (H)
©] &] NI]! a] Al eo] ro
o
CONNECTOR
1 REC SIGNAL OUT (L-CH)
2 | GROUND
3 | PLAY SIGNAL IN (R-CH)
Hi main circuit Boar
NOTES:
© This circuit shown i on the conductor indicates printed circuit on
the back side of the printed circuit board.
* Values indicated in[____] are under no signal condition.
Unless otherwise specified, voltage measurement conditions are that tape
travel is at STOP, tape mode at METAL, and NR switch at OFF.
DOLBY IN ......... Voltage value at IN (NR select switch) mode.
DISG: ieee ceceases Voltage value at DISC (NR select switch) mode.
FF/REW ............ Voltage value at FF/REW mode.
MUTINGON ...... Voltage value at muting ON mode.
For measurement, use VTVM.
© The supply parts number is described alone in the replacement parts list.
¢ This circuit board diagram may be modified at any time
with the development of new technology.
10
[B+ tos7v] [8-10.53
RS-M228X
B- 10.53V
8
RS-M228X
1
B+ 10.57V
B+ 7.88V
Connection Point (b)
B- 16.83V (-17.80V)
Connection Point (c)
B+ 16.74V (17.71V)
* For Australia, Asia, Latin America,
6
* For United Kingdom and Austsralia.
IN
ee a.
mal
| * For all European areas except United Kingdom,
. Asia, Latin America, Middle East and Africa areas.
Middle East and Africa
act
areas.
« Fora
IC1 I1Cc2 IC3
[M5219L] [NE646N] [NE646N]
7 [-0.02V] 5 | 0.02V 1 ov, 9 ~7.82V 1 ov 9 =7.82V
2 | 0.02v| 6 | 0.02V 2 OV | 10 =0.01V 2 OV | 10 OV
3 | 0.02V] 7 |-0.02V 3 |-001V1 11 0.01V 3 ov 11 0.08V
4 |-6.81V| 8 | 6.83V L 4 ov | 12 OV 4 ov | 12 =0.01V
5 | 0.02V/ 13 = 5 | 0.02v/ 13 =
6 | 0.05V] 14 | poLpy IN 0.05V 6 | 0.038V] 14 | po.py iN 0.01V
3.14V 7 |-0.08V | 15 3.13V
7 | 0.02V | 15 | DoLBY IN 0.05V a] =. (46 7 B8V
=} 46 7.88V
IC6
[AN6256]
1 | 10.57V | 9 0.01V
0.01V
2 | 10.56v | 10 (0)
3 10.56V | 11 | OV
4 OV | 12 | -10.53V
4.61V
| (0.07%) | 19 OV
~10.37V
8 |(-10.39v) | 14 ov
0.01V | 15 OV
8 0.01V | 16 | 0.01V
(N * For Asia, Latin America,
Middle East and Africa areas.
| |
im
li European areas.
POWER SUPPLY CIRCUIT BOARD
IC4
[M5218L]
1 0.01V| 5 0.01V
2 0.01v) 6 | 0.01V
3 0.01V; 7 | 0.01V |
4 |-10.53V| 8 | 10.57V
IC5
[M5218L]
7 OV] 5 | O.01V
2 ov| 6 | 0.01V
3 ov] 7 | 0.01V
4 |-10.53V| 8 | 10.57V
1C7
[M5230L]
OV 5_| 1.80V
2 OV 26 day
3 | -11.18V] > | 16.74V
(-11.17V) (17.71V)
4 1ciFaoy| 8 | ov
* For all European areas
and Australia.
Q1
[2SC945-Q]
B | OV (0.68V) [disc 0V]
C/O0V Vv) [OV]
Ef;ov (ov) [—]
Q2
[2SC945-Q]
B OV (0.68V) [disc OV]
Cfov. Vv) [ov]
E OV Ov) [—]
@
[2Scg
=0.35V (0.04
oV
ov. (0
1
B
Cc
E
Q4
[2SC945-Q]
=0.35V (0.04V) [FF REW 0.68V]
OV (OV) (0V]
m| QO]
OV (OV) [=]
Q5
[2SK104]
Ov
Ov
=10.13V
| D
s
G
m) QO] o
Q6
[2SK104]
Q7
[2SK104]
D OV
Ss OV
G |0.04V
Qs
[2SK104]
m|O|o
Qg
[2SC965Q]
=0.10V (0.68V)
OV (OV)
m|Q |
OV. (OV)
Q10
[2SC965Q] [
—0.10V (0.68V) |
OV (OV)
m|O}o@
my} ©} 0
OV (OV)

Qi Q11
[2SC945-Q] [2SD965]
| B | OV (0.68V) [disc OV] B [-0.12V (-0.12V) [MUTING ON 0.68V]
Cl10V Vv) [OV] C OV (OV) (0 V] |
E | ov ©v) [-] E OV (OV) [—]
Q2 Q12
(2SC945-Q] {2SD965]
B | OV (0.68V) [disc OV] B |-0.12V (-0.12V) [MUTING ON 0.68V]
C[0V Vv) [OV] C OV (OV) [OV]
E [ov (Ov) [—-] E OV (OV) [—] J
Q3 Q13
[2SC945-Q] [2SB641]
B | —0.35V (0.04V) [FF REW 0.68V] B | 10.52V (10.52V)
A] * For all European areas Cc Ov (OV) [OV] C | =10.29V (—10.30V)
7 and Australia. E OV (OV) [—] E 10.57V_ (10.57 V) |
‘ Q4 Q14 Q15
[2SC945-Q] [2SC945-Q] [2SC945-Q]
B |-0.35V (0.04V) [FF REW 0.68V] B | OV B [0.70V (OV)
C OV (OV) [OV] Cc | OV c OV (OV)
: E OV (OV) [—] E | OV E OV (OV) |
i
Q5 Q16 Q17
[2SK104] [2SC945-Q] [2SC945-Q]
B |-10.47V (-10.48V) f B [-1.53V (OV)]
Le 6.29V_(6.29V) C | -2.11V (3.49V) |
| E [-10.53V (-10.53V) | E; ov (Vv))
Q6 Q18 Q19
_ [2SK104] [2SB641] [2SB641]
; B OV (2.86 V) B | 0.03V (8.38V)
C |-0.11V (3.45V) | © | 0.04V (0.05V) |
D E |-2.40V (3.49V) | E | 0.01V (8.41V)
Q7 Q20 Q21
[2SK104] [2SD592] [2SA999]
[D| ov B | -9.83V (-10.53V) B | 1.42V (-10.49V) |
s OV 'C | 0.5V (-10.52V) C 1 0.73V (~10.52V)_
G_|0.04V E |-9.96V (-10.53V) E | 1.12V (-10.53V) |
Q8 Q22 Q23
[2SK104] [2SA999] [2SC945-Q]
B | 0.36V (-10.47V) | [Bi ov!
C | 0.73V (-10.52V)
E | 1.13V (-10.53V)
Qg Q24 Q25
[2SC965Q] [2SC945-Q] [2SB641]
B
|-0.10V
(0.68V)|
B
|
0.23V
(0.23V)
B
|
15.33V
(16.26
V)
|
Cc ov ov C | 15.36V (16.28 V) C | -10.37V (-10.25V)_
E ov (OV) le OV (OV) | E | 15.34V (16.27)!
Q10 Q26 Q27
[2SC965Q] [2SC 1847-Q] [2SA886Q]
B [-0.10V (0.68 V) B [ 11.22V (11.22V) BT Si1718V E11
C ov (OV) C | 16.65V (17.61V) C | -16.64V (-17.66V)
[e ov (OV) E | 10.57V (10.57V) | E | -10.53V (-10.53V)
TERMINATIONS
‘aa
gg
ht
1C1,
4,
5,
7,
301
8c
Q1—25, 201—222,
224, 301—304
Cathode
Cao—fq—o a
D1—26, 28, 29, 201,
202, 301—308
Cathode
Anode
Cao—f—o A
D27, 30—37
Cathode
cao—{t}-0 A
~~
Anode
LED1—4
RS-M228X
RS-M228X
NOTES: RESISTORS CAPACITORS
ERD ....Carbon ECBA ...... Ceramic ECED ......Electrolytic
ERG ......Metal-oxide ECGD...... Ceramic ECEON ...Non polar electrolytic
ERS ...... Metal-oxide ECKO...... Ceramic ECQS ...... Polystyrene
ERO ...... Metal-film ECCD...... Ceramic ECSO...... Tantalum
ERX ...... Metal-film ECFO...... Ceramic acs ...... Tantalum
ERQ ...... Fuse type metallic ECQM...... Polyester film
ERC ......Solid ECQE ...... Polyester film
ERE :zis.c8 Cement ECOF ...... Polypropylene
REPLACEMENT PARTS LIST
Important safety notice
Components identified by A mark have special
characteristics important for safety.
When replacing any of these components, use
only manufacturer’s specified parts.
Ref No. | Part No. Ref No. Part No. Ref No. Part No. Ref No. Part No. Ref No. Part No. Ref No. Part No. | Part Name & Description
RESISTORS R 138, 139 ERD25FJ103 R 281, 282 ERD25FU8R2 C 59,60 ECEAS50Z1 SPARK KILLER TRANSFORMER
an R 140 ERD25FJ182 R 283, 284 ERD25TJ333 C61,62 ECEAS50ZR68 So GR eee = ak 35
R1,2 ERD25TJ474 R 141(DB] ERDS50FJ101 R 289, 290 ERD25TJ154 C 63, 64 ECEA50Z1 Z1 A ECQU2A103MF T1
R3,4 ERD25TJ273 [For all European areas.) | R 291, 292 ERD25TJ105 C 65, 66 ECEA1ES200 {D] A QLPD69ELE AC Power Transformer
R5,6 ERD25FJ100 [AN] ERD25FJ101 R 293, 294 ERD25TJ155 TRANSISTORS [For all European areas except United Kingdom.]
R7,8 ERD25FJ181 [For Australia, Asia, R 301, 302 ERD25FJ272 C 67,68 ECQV05273JZ aot RTA [IN] A QLPN76ELE = AC Power Transformer
R 9, 10 ERD25TJ563 Latin America, Middle R 303, 304 ERD25TJ224 C 69,70 ECQV05123JZ Q 1, 2,3, 4 28C945-Q [For Asia, Latin America, Middle East and Africa
R13,14 ERD25FJ560 East and Africa areas.] R 305, 306 ERD25TJ563 C71,72 ECQV05183UZ Q5,6,7,8 2SK104 areas.]
R 15,16 ERD25TJ104 [For all European areas.] | R 307, 308 ERD25TJ105 C 73,74 ECQV05683JZ QQ, 10 2SD965Q [BA] A QLPZ21ELE = AC Power Transformer
R19,20 ERD25FJ181 R 144 ERD25FJ122 R 309, 310 ERD25TJ104 C 75,76 ECQV05333JZ Q11,12 2SD965 [For United Kingdom and Australia.]
R 21, 22 ERD25FJ561 R 145 ERD25FJ681 C77, 78 ECKD1H561KB Q 13 2SB641
R 23,24 ERD25FU472 R 146 ERD25FJ122 R 311, 312 ERD25TJ184 C 79,80 ECKD1H152KB | Q 14, 15, 16, 17 COILS
R
147
ERD25FJ681
R
313
ERD25FJ332
C
81,82
ECKD1H103MD
2SC945-Q
Saree
R 25,26 ERD25FJ562 R 148 ERD25TJ223 R 315, 316, 317, 318 C 83,84 ECCD1H101KC |Q18,19 288641 L1,2 QLQX0332KWA Peaking Coil
R 27, 28, 29, 30 ERD25FJ562 C 85,86 ECQV05104JZ Q 20 2SD592 L3,4 QLQX0343KWA Bias Trap Coil
ERD25FJ102 R 149 ERD25TJ154 R 319, 320 ERD25FJ472 Q 21,22 2SA999 L5 QLQX1021Y Peaking Coil
R 31,32 ERD25TJ684 R 150 ERD25FJ222 R 321, 322 ERD25TJ684 Cc 89 ECEA1ES200 Q 23,24 2SC945-Q L7 QLB0198 Bias Oscillation Coil
R 33, 34 ERD25TJ473 R 151 ERD25FJ102 R 323 ERD25TJ224 Cc 90 ECEA1AS470
R 35,36 ERD25TJ274 R 152, 154 ERD25FJ562 R 324 ERD25TJ104 ca ECEA5O0Z1 Q 25 2SB641 FUSES
R 37, 38 ERD25FJ332 R 155 ERD25FJ471 R 325 ERD25TJ473 Cc 100 ECEA1HS100 Q 26 2SC1847Q
R 39, 40 ERD25FJ181 R 156 ERD25FJ103 R 326, 327 ERD25FJ103 C 101, 102 ECKD1H181KB Q27 2SA886-Q F1
R41 ERD25TJ184 R 157 ERD25FJ331 R 328 ERD25FJ221 C 103 ECQP1153JZ Q 201, 202 2SK104 [DB) A XBAQo0007 Fuse (T 400mA)
R 42 ERD25TJ184 R 158 ERD25FJ103 C 104 ECFDD153KXY | Q 203, 204 2SC945-Q [For all European areas.]
R 43,44 ERD25TJ274 R 159, 160 ERO25TKG1502 | R 329 ERD25TJ684 C 105 ECQV05153JZ_ —_| Q 205, 206, 207, 208, 209, 210, [N] A. XBA2FO3NM100
R 161 ERO25TKG5601 | R 330 ERD25FJ472 Cc 106 ECQM1H822JZ 211, 212, 213, 214, 215, 216, Fuse(300mA)
R45 ERG1ANJ820 R 331 ERD25FJ 182 C 107,110 ECEA1ES470 217, 218, 219, 220 [For Asia, Latin America, Middle East and Africa
R 46 ERG1ANJ820 R 162 ERO25TKG2702 | R 332[DB] ERD2FCG100P 28D1010 areas.]
R 47, 48 ERD25TJ154 R 163, 164 [For all European areas.] | C111 ECEA1HS100 Q 221, 222, 224 F2
R 49,50 ERD25FJ471 (DB) ERD2FCJ181 [AN] ERD2FCG100 C112 ECEA1VS102 2SC945-Q {(DB] A XBAQo007 Fuse (T 400mA)
R 51, 52, 53, 54 [For all European areas.] [For Australia, Asia, C113 ECEA1CS471 Q 301 2SB641 [For all European areas.
ERD25TJ154 [AN] ERD25FJ181 Latin America, Middle C114 ECEA1CS471 Q 302, 303 2SC945-Q F3
R55 ERD25FJ562 [For Australia, Asia, East and Africa areas} | C 115 ECEA1HS100 =| Q 304 2SB641 [DB] A XBAQo006 Fuse (T 315mA)
R56 ERD25FJ103 Latin America, Middle R 333[DB] ERD2FCG181P | C 116, 117 [For all European areas.]
R57,58 ERD25FU102 East and Africa areas.] [For all European areas.] A ECEA1CS221 DIODES & RECTIFIERS | F 4 [DB] XBAQ007 Fuse (T 400mA)
R59,60 ERD25TJ274 R 169, 170, 171, 172 [AN] ERD2FCG181 C 120, 121 {For all European areas.]
R 61, 62 ERD25FJ392 ERD25TJ225 [For Australia, Asia, A ECEA1ES332 01,2 MA161
R 202, 204 ERD25TJ104 Latin America, Middle C124 A ECEA1CS102 D 11, 12, 13, 14, 15, 16, 17, SWITCHES
R 63, 64 ERD25TJ333 R 205, 206 ERD25FJ101 East and Africa areas.] C 125, 126 18, 19, 20, 21, 22, 23, 24,
R65,66 ERD25FJ681 R 207, 208 ERD25TJ474 R 334 ERD25FJ103 [DBN] A ECKD1H103MD 25,26 MA161 $1 QSSE203 Slide Switch
R67 ERD25FJ121 R 209, 210 ERD25TJ105 {For all European areas, D 27 SM112 (Record/Playback
R68 ERD25FJ121 R 211,212 ERD25TJ154 VARIABLE RESISTORS Asia, Latin America, D 28 MA161 Selector)
R 69, 70 ERD25FJ331 R 213, 214 ERD25TJ473 Midole East and Africa D29 SVDRD8.2EB $2 QSR8403 Rotary Switch
R71, 72 ERD25Fu392 R 215, 216 ERD25FJ472 VR 1, 2, 3, 4EVNM4AA00B24 areas.] D 30, 31, 32, 33, 34, 35, 36, 37 (NR Selector)
R 75, 76, 77, 78 R 217, 218 ERD25TJ473 VR 5,6 EVNM4AA00B54 | C 201, 202 ECEA25Z4R7 A SM112 $3 Qsw4214 Push Switch
ERD25FJ152
R
219,
220
ERD25TJ333
VR
7,8
QWKGTA024A14
|
C
203,
204
ECEA50Z1
D
38,
39,
40
(Input
Selector)
R79 ERD25FU103 R 221, 222 ERD25FJ103 VR 9,10 EVNM4AA00B15 | C 205, 206, 207, 208 MA161 S4 Qsw2236 Push Switch
R 80 ERD25TJ104 R 223, 224 ERD25TJ473 VR 201, 202, 203, 204 ECQV05104JZ (REC Mute ON/OFF)
R 81,82 ERD25TJ563 R 225, 226 ERD25FJ470 EVNMOAA00B54 | C 209, 210 ECEQV05334JZ |D 41,42 RD20EB3 S5 A QSW117AS Push Switch
R 227, 228 ERD25TJ104 VR 205, 206, 207, 208 C 211,212 ECCD1H221J D 45 MA161 (Power ON/OFF)
R 83,84 ERD25TJ473 R 229, 230 ERD25FJ332 EVNMOAAO0B14 | C 213, 214, 217, 218 D 201, 202 MA161 S6, 7 QsB0251 Leaf Switch (Auto Tape
R 85, 86 ERD25FJ101 R 231, 232 ERD25TJ473 VR 301 EVNM4AA00B53 ECQM1H103JZ D 301, 302, 303, 304, 305, 306 Detector)
R 87,88 ERD25FJ680 R 233, 234, 235,236 VR 302 EVNM4AA00B14 | C 215, 216, 219, 220 MA161 $8,9 QSB0251 Leaf Switch (Play/Fast
R 89,90 ERD25FJ102 ERD25TJ104 ECCD1H101J D 307 RD20EB3 Wind SW)
R 100 ERD25TJ123 R 237, 238 ERD25FJ103 CAPACITORS C 221, 222, 223, 224 D 308 MA161 $10
R 101 ERD25FJ562 R 239, 240 ERD25TJ333 ECEA25Z4R7 (DN] A QSR1410 Rotary Switch
R 102, 103, 104 C1,2 ECEA16M10R C 225, 226, 227, 228 (AC Power Voltage
ERD25TJ473 R 241, 242 ERD25FJ102 C5,6 ECKD1H471KB ECQV05104JZ | LIGHT EMITTING DIODES selector)
R 105 ERD25TJ273 R 243, 244 ERD25TJ473 C7,8 ECKD1H391KB | ¢ 229, 230, 231, 232 [For all European areas except United Kingdom,
R 106 ERD25TJ473 R 245, 246 ERD25FJ101 C9, 10 ECEA16M10R ECQM1H332JZ | LED1 LN216RP Asia, Latin America, Middle East and Africa
R 107 ERD25TJ104 R 247, 248 ERD25TJ473 C11,12 ECKDIH102KB | C 233, 234 ECKD1H331KB | LED 2 LN316GP areas.]
R 249, 250 ERD25FJ103 C 13, 14 ECEA1AS221 C 235, 236 ECQV05104JZ LED 3 LN216RP
R108, 109 ERD25TJ563 R 251, 252, ERD25FJ102 C 15,16 ECQV05273JZ C 237, 238 ECQM1H103JZ | LED 4 LN416YP JACKS
R112 ERD25TJ273 R 253, 254 ERD25FJ392 C 17,18 ECEA1HS100 C 239, 240 ECQV05104JZ a>.
R113 ERD25FJ222 R 255, 256 ERD25TJ333 C 19,20 ECQV05123JZ | C 241, 242 ECEA16M10R INEGRATED CIRCUITS j|J1,2 QJA0451 MIC Jack
R114 ERD25TJ104 R 287, 258 ERD25TJ104 C 21,22 ECEA1AS101 C 243, 244 ECEA1HS100 Se ee ee QJA0259 Headphones Jack
R115, 116 ERD25FJ472 R 259, 260 ERD25FJ472 C 247, 248 ECEA1ES470 IC 1 M5219L J4,5,6,7
R117 ERD25FJ222 C 23,24 ECEASOMR33R | C 249, 250 ECCD1H151KB | Ic 2,3 NE646N QEJ5028S Jack Board (LINE IN/OUT)
R118 ERD25TJ333 R 261, 262 ERD25TJ333 C 27,28 ECCDIH470KC | C 301,302 ECEAS0ZR47 IC 4,5 M5218L
R 120 ERD25FJ472 R 263, 264 ERD25FJ682 C 29, 30 ECQV05273NZ C 303, 304 ECEA1HS100 IC6 AN6256
R121 ERD25TJ104 R 265, 266 ERD25FJ472 C 31, 32 ECEQM1H472JZ | C 305, 306 ECEA50Z1 IC7 M5230L :
R 122 ERD25FJ152 R 267, 268 C 33,34 = ECEA1HS100 C 307 ECEA1ES101 IC 201, 202 UPC1252H2
R 123 ERD25FJ122 [DB] ERD2FCG220 C 35,36 = ECEASOZR33 IC 203, 204 UPC1253H 2
R 124 ERD25TJ273 [For all European areas.] | C 37, 38 ECQV05104JZ C 308 ECQV05473UZ IC 205, 206 NJM4558DF
R 125 ERD25FJ1RO [AN] ERD25FJ220 C 39,40 ECQM1H392JZ | Cc 309 ECEA1HS100 IC 301 BA6138
R 126 ERD25FJ100 [For Australia, Asia, C 41, 42, 43, 44 IC 302 AN6552
R 127, 128 ERD25FJ562 Latin America, Middle ECEA1HS100 COMBINATION PARTS | ic 303 AN6870N
R 129 ERD25FJ100 East and Africa areas.] C 45, 46 ECEA50ZR68
R 130 ERD25FJ103 R 269, 270 ERD25TJ393 C 47,48 ECEQV05473JZ | cR1,2 EXRP102K103W MULTIPLEX FILTERS
R131 ERD25TJ563 R 271, 272 ERD25FJ223 C 49, 50 ECEA1HS100 CR 3,4 EXRP182K392W |
R 132 ERD25TJ223 R 273, 274 ERD25FJ332 C 51,52 ECEA1AS221 CR 5,6 EXRP102K562W | mpx1.2 QLM9Z9K
R 133 ERD25TJ563 R 275, 276 ERD25TJ333 C 53, 54 ECEA1HS100 CR7,8 EXRP100K184W 7
R 134,135 ERD25FJ561 R 277, 278 ERD25TJ394 C 55,56 ECQM1HS562JZ |CR9,10 EXRP561K822W
R 136, 137 ERD25FJ101 R 279, 280 ERD25FJ102 C 57,58 ECEA1HS100 CR 11,12 EXRP821K123W