Pioneer SX-990 Setup guide

INSTALLATION, PERATION
ND SERVICE MANUAL
lncluding PARTS LIST, CtRCUtT DtAGRAMS.
TROUBLESHOOTING AND MOUNTING TEMPLATE
PIONEEIiR"

FE URES
LINE VO GE SELECTION AND FUSE
SWITCHING LINE VOLTAGE SETTING
ln order to remove the fuse, turn the fuse cap located
on the line voltage selector switch in the direction
indicated by an arrow. Then remove the fuse plug
from the unit. Put the fuse plug back so that the
proper line voltage marking can be seen through the
cut in the edge of the plug.
Whenever the set position of the selector switch is
changed, check the rating of the fuse. A 1-ampere fuse
is to be used for either 220V or 24OY operation and
2-ampere fuse for any of 110V, 117V, or 130V
operation. lf the rating of the fuse is proper, install
the fuse in the fuse cap.
FUSE REPLACEMENT
When the fuse is blown, remove the fuse cap and
reolrce the fuse with a nerry one.
AND FUSE
HIGH-PERFORMANCE FM TUNER
An FET (field-effect transistor) is used in the radio-frequency amplifir to attain a high
sensitivity and selectivity. Further, four lCs (integrated circuits) are used for the
intermediate frequency amplifier to eliminate interference and noise.
BUILT-IN EXCELLENT FM MPX CIRCUIT
This wvitching circuit having excellent separation and frequency response is built in for
reproduction of reality music.
BUI LT-IN HIGHLY-SENSITIVE
RADIO RECEPTION FERRITE ANTENNA FOR AM
The ferrite antenna provides high-sensitivity reception of AM broadoast programs.
SPECIAL CIRCUITRY FOR VERSATILITY
The high output given by strictly selected transistors, two sets of loudspeaker terminals
and phono terminals, and the provision for using a microphone make Model SX'990
suitable for the professional use a well a the family use.
A VARIETY OF ACCESSORIES
Accessories include the program lamps that indicate the program being played, the
tuning meters vertically arranged for facilitating selection of an FM broadcast program,
the loudspeaker selector switch, tape monitor switch, etc., all for enjoyable use of Model
sx-990.
ELEGANTLY DESIGNED FRONT PANEL
Newly designed knobs are uniquely arranged on the silver tone panel.
Take off the fuse cap by turning it with a coin,
etc. in the direction indicated by the arrow mark.
Fis. 1

t
PHoNEs BASS TREBLE BALANG:E VoLUME TAPE .MoDE
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PROGRAM
1. SPEAKERS SWITCH
A combination of the power onloff switch and the
loudspeaker system selector switch.
Fis. 4
POWER OFF: .....The equipment is deenergized.
The power supplied from the
SWTTCHED AC outtet (36) is discon_
tinued simu ltaneously.
A: '...'."..'...'.........Sound is reproduced from the loud-
speaker system connected to the
SPEAKER OUTPUT A terminats (31
and 32).
SPKR OFF: '...... Loudspeakers stop sounding.
This position is selected when using a
stereo headphone.
B:'..........'...".......The loudspeaker system connected to
the SPEAKER OUTPUT B terminals
(33 and 34) is put in operation.
A + B: The loudspeaker systems connectd to
SPEAKER OUTPUT A and B termi_
nals are put in operation.
SPEAKERS
Fis. 5

2. TUNING METERS
When tuning the receiver to an AM broadcasting
station, adjust the TUNING knob (4) so the pointer
of the lower one of the meters deflects largely
rightward.
When tuning the receiver to an FM broadcasting
station, adjust the TUNING knob so the pointer of
the lower meter deflects largely rightward and, in
addition, the pointer of the upper meter is at the
center.
Tuning to AM Radio Station Tuning to FM Radio Station
Pointer deflecling
largely righiward
Fis. 6
3. FM STEREO INDICATOR
This lamp is lit during reception of an FM stereo
program.
4. TUNING KNOB
The knob for tuning the receiver to an AM or FM
broadcasting station. Adjust the knob for the best
tuning while observing the tuning meters (2).
5. SELECTOR SWITCH
The switch for selecting the program source,
AM: ...'.'.......".. For reception of an AM program.
FM MONO: ..,.. For reception of an FM monaural
program.
FM AUTO: ...'.. For automatically selective reception
of stereo or monaural FM Program.
PHONO 1............For playing a disk record by using the
turntable connected to the PHONO 1
terminals (17).
PHONO 2lMlC: For playing a disk record by using the
turntable connected to the PHONO 2
terminals (18) or for using a micro-
phone by inserting its cord plug into
the MIC jack (16). (When the micro
phone is connected to the jack, the
turntable connected to the PHONO 2
terminals cannot be used.)
6.
K: ..'....'....... For using the cartridge tape player,
reproducing the TV audio output, or
operating other equipment connected
to the AUX terminals {20}.
When the SELECTOR switch is operated, the
program indicator lamp corresponding to the select-
ed source lights.
PHONES JACK
When using a stereo headset, insert its plug into
this jack. For the headset to be used with Model
SX-990, PIONEER's ModelSE-20, SE-30 or SE-50 is
recommended.
When a longer cord is required for the stereo
headset, use PIONEER's Model JB-23 extension
cord separately avai lable.
When desiring to connect two stereo headsets,
use PIONEER's Model JB-22 "Y" cord separately
available.
BASS CONTROL
When this knob is turned clockwise, bass is increased;
when turned counterclockwise, decreased. With the
knob set to the center, the frequency response curve
is flat. The center and outer knobs of this double
knob are friction-coupled with each other, and the
tone of both left and right channels can be adjusted
simultaneously by turning either knob. The center
knob is for the left channel, and the outer knob is
for the right channel. When adjusting the tone of
only one of the channels. turn the knob for that
channel while holding the other knob by the other
hand.
RTGHT bUnruruel
(cH .R)
7.
LEFT CHANNEL
(cH .L) Fig. 7

8. TREBLE CONTROL
Use of this knob is similar to that of the BASS
control knob (7).
9. FILTER SWITCHES
LOW: A switch f or suppressing low-frequency
noise or hum.
HIGH: A sruitch for suppressing high-frequency
notse.
These switches are of the pushbutton type. When
once the button is pressed, the switch turns on, and
when pressed once again. it turns off.
10. BALANCE CONTROL
This knob is used for adjusting the stereophonic
balance. When the volume of the right channel
loudspeaker is smaller, turn the knob clockwise
toward RIGHT; when left channel volume is smaller.
counterclockwise toward LEFT.
BALANCE
olume of When the volwre of
I right channel
is loudspeaker is
smaller
LEFT FIIGHT
11. VOLUME CONTROL
The volume increases when the knob
clockwise.
Fis. 8
turned
12. LOUDNESS SWITCH
With this switch turned on when the sound volume
is low, insufficiencies of bass and treble are com-
pensated for. When the sound volume is high, it is
recommended to keep this switch turned off.
13. MUTING SWITCH
Turning on this switch, the noise generated when
tuning the receiver to an FM station can be
eliminated. lf Model SX-990 is used where the FM
field strength is low, keep this switch turned off
since the program sound is also suppresed with the
switch turned on.
sx,990
orerr --
OUTPUI
ORlcHrJ
r- LEFro
l-- RtcHTo
oLEFT ___-l
OUTPUT
oRTGHT--J
oLEFT ----l
OUTPUT
onrexr-J
oLEFr ---.1
OUTPUT
oRtcBr-J
14. TAPE MONITOR SWITCH
Turn on this switch for listening to or monitoring
only the signal reproduced by a tape deck (or tape
recorder). When not using the tape deck (or tape
remrder), keep this switch turned off. Otherwise,
loudspeakers will not sound.
15. MODE SWITCH
Functions as follows:
REV....... Stereo, with left and right channel
input signals exchanged for each
other.
STEREO... Normal stereo
L'..'.......'... Monaural play with only the left
channel input signal fed to both
channel loudspeakers.
R...'."....... Monaural play with only the right
channel input signal fed to both
channel loudspeakers.
L + R ..'..... Monaural play with both left and right
channel input signals mixed together
and reproduced from both channel
loudspeakers.
lst.-.n
r---F
.NPUT | | ourdur
-i,Gnro l I oRrGHrJ
f- LEFT O
INPUT
[- nrerro
[- LEFT O
INPUT
l-nrasro
Fig. 9
16. MIC (MICROPHONE) JACK
When a microphone is connected to this jack, the
signal fed from the turntable connected to the
PHONO 2 terminals (18) on the rear panel is
disconnected.

I
The upper ones of the terminals 17,18,20,21 ,22,
28 and 29 are for the left channel respectively; the
lower ones, for the right channel
17. PHONO 1 TERMINALS
MAG: ......... Connect here a turntable equipped
with a moving magent cartridge.
CER:.......... Connect here a turntable equipped
with a ceramic or crystal cartridge.
NOTE: Two turntable cannot be connected
to the MAG and CER terminals
simu ltaneously.
18. PHONO 2 MAG TERMINALS
Connect here a turntable equipped with a moving
magnet cartridge.
TERMINALS AND CONNECTORS ON THE REAR NEL:
Fis. 10
19. GND (GROUND) TERMINAL 1
lf the turntable or other equipment used with
Model SX 990 is provided with a ground wire,
connect the wire to this terminal.
20. AUX. (AUXILIARY) INPUT TERMINALS
Connect here the output of a cartridge tape player
21. TAPE MON TERMINALS (TAPE PLAY-
BACI( INPUTS)
Connect the line output or monitor output of tape
deck (or tape recorder) to these terminals
22.TAPE REC TERMINALS (TAPE RECORD.
ING OUTPUTS)
Connect the line input of a tape deck (or tape
recorder), Signal is always supplied to these termi-
nals while SX 990 is workinq; however, the signal

cannot be controlled with the VO LUME ( 1 1),
BALANCE (10), TREBLE (8) or BASS (7) controt
on the front panel.
23. TAPE REC/PB CONNECTOR
(DI N TYPE)
lf the tape deck (or tape recorder) to be used with
Model SX-990 is provided with a record/playback
connector of the DIN type, the tape deck (or tape
recorder) can be connected to Model SX-ggO for both
recording and playback (and monitor) by simply
connecting the DIN cable.
When this cable is used, connections to terminals
(21l. and(221 are unnecessary.
The detail of connection is shown on page 10.
Connectjon of tape deck (or tape recorder),,;
24. AM FERRITE ANTENNA
Where the field strength is high, adjust the direction
of this ferrite antenna for gmd reception, without
using an external antenna. lf good reception cannot
be obtained, see page 9.,,Antenna Connection and
Grounding".
25, AM ANTENNA INPUT TERMINAL
Connect a lead wire or outdoor AM antenna to this
termina I if the ferrite antenna (24) cannot get
good reception.
26. GND (GROUND) TERMINAL 2
Connect a ground wire to this terminal.
27. FM ANTENNA INPUT TERMINALS
Connect an FM antenna to these terminals.
NOTE: For the details of AM antenna, FM
antenna and grounding, see ,,Antenna
connection and grounding" on page 9.
28. !RE-AMP OUTPUT TERMTNALS
The output of preamplif ier stage, which is the signal
having passed the tone control circuit is always
supplied to these terminals.
29. MAIN-AMP INPUT TERMINALS
These are input terminals of the power amplifier
stage of Model SX-990.
The PRE-AMP OUTPUT (28) and MA|N-AMP
INPUT (29) terminals are connected to each other
with the jumper plugs. With these plugs removed,
the preamplif ier and power amplif ier stage of
Model SX-990 can be used apart. This system is
convenient for composing a multi-amplifier system
and other purposes.
30. CENTER CHANNEL OUTPUT TERMI.
NAL
The signals of left and right channels are mixed
together and supplied to this terminal at all times.
The terminal may be used for composing a 3_D
system or connecting a center-channel amplifier.
31. & 32. SPEAKER OUTPUT A TERMI.
NALS
Model SX-990 is designed to permit connection of
two sets of stereo loudspeaker systems.
Connect the first set of loudspeaker system (system
A) to these terminals; the right channel to terminal
(31) and the left channel to terminal (32).
33. & 34. SPEAKER OUTPUT B TERMI-
NALS
Connect the right channel loudspeaker of the second
loudspeaker system (system B) to terminal (33) and
the left channel loudspeaker of this system to
terminal(34).
For ornetion SPEAKER
OUTPUT A ad supplied as
accessories nrust irstr:uctions
under "Connection o system,, on p4e
9, for the oorect use
35. LINE VOLTAGE SELECTOR AND
FUSE HOLDER
This selector is used for setting the SX-990 to suit
the line voltage to be supplied. lt also serues as a fuse
holder.
For the selector setting and fuse replacement proce.
dures, refer to the article "LINE VOLTAGE SELEC-
TION AND FUSE". (Pase t)
36. SWITCHED AUXILIARY AC OUTLET
A power of 23O VA can be supplied to a turntable
or other eqLipment from this outlet. The power
supply is turned on and off corresponding to the
turning-on and off operations of the SPEAKERS
switch (1) on the front panel.
37. UNSWITCHED AUXILIARY AC OUT-
LET
The power outlet also having a capacity of 230 VA
total. The power from this outlet is supplied
regardless of the operation of the SpEAKERS switch
(1).
38. AC POWER CORD
After all the external equipment is connected to
Model SX-990, connect this cord to a commercial
power outlet having a sufficient capacity.

a
CONNECTION OF LOUDSPEAKER SYSTEM
To connect a loudspeaker, take out a speaker
connector plug from the accessories bag, and con-
nect it to the leads of the loudspeaker as illustrated
in Fig. 11.
Be sure to connect them for the correct polarity.
When the plugs have been connected to loud-
speakers, connect the plug of the right channel
loudspeaker to the SPEAKER OUTPUT A terminal
(31) and that of the left channel loudspeaker to the
SPEAKER OUTPUT A terminal (32). (See Fig. 2.1
When using an additional loudspeaker system,
connect the speaker connector plugs to the loud-
speakers as described above, and connect the plug of
the right channel loudspeaker to the SPEAKER
OUTPUT B terminal (33) and that of the left
channel loudspeaker to the SPEAKER OUTPUT B
terminal (34).
ANTENNA CONNECTION AND GROUNDING
FM ANTENNA
When using Model SX-990 at a place of low field
strength or distant f rom the station, select the most
suitable FM antenna as follows:
. Use the accessory T-type indoor antenna when using
Model SX-990 within a wooden building near the
FM radio station. Connect the free and of the
vertical section of the antenna to the FM antenna
terminals (27]' as shown in Fig.12'
Expand the horizontal section of the antenna, and
determine its direction for good reception while
actually receiving a broadcast program. Fix the
horizontal section on a wall or other place in the
determined direction. For the operating procedure,
see "Reception of FM broadcasts" on page 1 1.
o When using Model SX-990 at a long distance from
the station, or within a building, install an outdoor
FM antenna, and connect it to the FM antenna
terminals (211 as in Fig. 13.
The FM antenna is various in type, consisting of 3 to
7 elements. Select the optimum antenna by consult-
ing a nearby radio, TV or hi-fi equipment sales store.
AM ANTENNA
When using Model SX-990 near the broadcasting
station or inside a wooden building, connection of
an external AM antenna is unnecessary. Adjust the
direction of the AM ferrite antenna (24) located on
the rear panel for the best radio reception while
actually listening to broadcasts, referring to "Re-
ception of AM broadcasts" on page 1 1.
SPEAKER PLUG
POSTTIVE (+)
NEGATIVE H
Fis. 11
lf good radio reception cannot be attained with the
AM ferrite antenna (24), use the accessory AM lead
wire antenna. Connect one end of the antenna to the
AM antenna terminal (25), and expand the wire
along a wallof the room. (See Fig. 12.)
lf input is still not enough, install an AM antenna
outdoors instead of using the lead wire antenna. (See
Fis. 13).
NOTE: A standard AM outdoor antenna can be
formed by purchasing PVC wire from an
electric appliance store and installing it 25
feet (7.5 m) above the ground for a
horizontal length of 50 feet (15 m), with a
feeder line 30 feet (10 m) long. These
antenna dimensions need not be so
precise, and may be as large as allowable
by the place of installation. However, the
height of the horizontal section of the
antenna should not be too low to attain a
good antenna effect.
SPEAKER TERMINALS
LOUDSPEAKER

GROUNDING
o Whether or not Model SX-990 is grounded does not
much affect the performance of the equipment.
However, grounding is recommended for stabiliza-
tion of the performance.
o Connect to the GND terminal 2 126l a ground
conductor leading to the earth.
AM FERRITE ANTENNA
CONNECTION OF TURNTABLE
lf the turntable to be used is equipped with a
moving magnet cartridge, connect the output
cords of the turntable to the MAG terminals of
PHONO 1 (17) on the rear panel; if equipped
with a ceramic cartridge, to the CER terminals
of PHONO 1 (171.
Connect the left channel output cords of the
turntable to the upper terminal, and the right
channel output cord to the lower terminal.
When using a monaural turntable, its output
cord may be connected to either upper or lower
terminal.
To use two turntables both having a moving
magnet cartridge, connect one to the pHONO 1
MAG terminals (17) and the other to the pHONO 2
- MAG terminals (18).
NOTE:1. When desiring to use a turntable equip
ped with a moving coil (MC) cartridge,
use a matching transformer "for MC
cartridge, or a separate head amplifier for
connection of the turntable to MODEL
sx-990.
2, The output cords of some turntables are
provided with plugs which do not meet
the input terminals of Model SX-ggO.
ln such a case, replace the plugs with the
pin plugs contained in the accessories
bag.
o The tape deck to be connected to Model sx-ggo
should have a record/playback preamplifier built-in,
such as PIONEER's ModelT-600, T-S00.
o The tape recorder to be connected should have
output terminals (line output) for external amplif ier,
or tape monitor terminals.
CONNECTION FOR TAPE RECORDING
Connect the LINE INPUT terminals of the tape deck (or
tape recorder) to the TAPE REC terminals (22) on the
rear panel. For this connection
to the tape deck (or tape recor
is for the left channel, and the
channel. lf the tape recorder is
the upper terminal.
CONNECTION OF CARTRIDGE TAPE PL ER
CONNECTION FOR TAPE PLAYBACK (OR TAPE
RECORDING MONITOR}
Connect the LINE OUTPUT or tape monitor termi-
nals of the tape deck (or tape recorder) to the TApE
MON terminals (21). Use of the terminals is similar
to that for the connection for recording described
above.
USE OF RECORD/PLAYBACK CONNECTOR
lf the tape deck (or tape recorder) is equipped with
a record/playback connector of the DIN type,
connect the connector to the TAPE REC/p.B.
connector (23) by using the DIN cable that is
separately available. ln this case, connections as
described in "Connection for tape recording,, and
"Connection for tape playback (or tape recording
monitor)" above are unnecessary.
When using a cartridge tape player, such as PIONEER,s
Model H-60, connect its output to the AUX terminals
(20) on the rear panel.

RECE ION
. Set the SPEAKERS switch (1) to the "A" position
after ensuring the following:
1. The BALANCE knob (10) is in the NORMAL
(center) position.
2. The VOLUME knob (11) is in the MIN position
(turned fully counterclockwise) .
3, ' The TAPE MONITOR switch (14) is set to OFF.
4. The MOD E switch (15) is set to the STER EO
position.
RECEPTION OF FM BROADCAST
1. Set the SELECTOR svvitch (5) to the FM AUTO
position.
2. Turn on the MUTING switch (18). (Keep the switch
turned off, if the field strength is low).
3. While observing the pointer def lection of the tuning
meters (2), tune the receiver to the desired station
by adjusting the TUNING knob (4).
The best radio reception is attained when the
pointer of the lower tuning meter deflects largely
rightward , and the pointer of the upper tuning
meter indicates the center.
When the tuned-in station is broadcasting a stereo
program, the FM stereo indicator (3) lights, and
Model SX-990 operates automatically for stereo
broadcast reception. lf tlre received program is
monaural, the indicator does not light, and the
equipment operates for monaural broadcast recep-
tion.
4. When the desired station has been tuned in, turn the
VOLUME control (11) gradually clockwise for the
desired volume. Adjust the BASS (7) and TREBLE
(8) controls as desired.
. lf Model SX-990 is used very f ar from the
broadcasting station, or where external noise is high,
the noise is suppressed and better reception can be
attained by keeping the SELECTOR sruitch (5) set
to the FM MONO position. With the switch in this
position, however, a stereo program is received as a
monaural program.
o lf good radio reception cannot be attained by the
operations instructed in ltems 1 through 4 above,
reconsider the antenna, referring to "Antenna con-
nection and grounding", on page 9.
RECEPTION OF AM BROADCAST
1. Set the SELECTOR switch (5) to the AM position.
2. While observing the pointer def lection of the tuning
meter (2), tune the receiver to the desired station by
adjusting the TUN ING knob (4).
The best radio reception is attained when the
pointer of the lower tuning meter deflects largely
rightward.
3. When the desired station has been tuned in, ad.iust
the voLUME (11), BASS (7) and TREBLE (8)
controls for desired volume and tone.
o lf good reception cannot be attained by the opera-
tions instructed in items 1 through 3 above, re-
consider the antenna, referring to the "Antenna con'
nection and grounding", on page 9.
o When the broadcasting station is very near, a much
distorted sound may result from the high field
strength. lf this occurs, shorten or remove the
antenna connected to the AM antenna terminal (25)
for the best radio reception.
1
PL OF DISK RECORD
Set the SELECTOR switch (5) to the PHONO 1
position, when operating the turntable connected
to the PHONO 1 terminals (17) on the rear panel.
Set the switch to the PHONO 2/MlC position when
operating the turntable connected to the PHONO 2
terminals (18),
lf the turntable to be operated is monaural, set
the MODE switch (15) to the "L" or "R" position.
Adjust the voLUME (11), BASS (7) and TREBLE
(8) controls for desired volume and tone.
'1. set the SELECTOR switch (5) to the AUX position.
2. The succeeding procedure is identical with its
counterpart of "Play of disk record" above.
USE OF MICROPHONE
2.
3@fii

2.
3.
Set the SELECTOR switch (S)to the pHONO 2lMtC
position.
Insert the microphone plug to MIC jack (16).
Speak into the microphone. Adjust the volume and
tone as desired. When the microphone is used near
the loudspeaker system, do not increase the volume
too much, or howling may occur.
When a microphone is connected to Model SX_ggO,
the turntable connected to the PHONO 2 terminals
cannot be used. The equipment operates for
monaural reproduction regardless of the position
which the MOD E switch (1 5) is set to.
RECORDING
The same signal as fiat reproduced from loudspeakers
is always supplied to the TAPE RECterminalsl22l .
According to the program source desired to be
recorded, operate the SELECTOR swjtch (5) and
MODE sruitch (15), referring to ,,Reception of
broadcast" and "Play of disk record,,. The signal
does not corrcern fre VOLUME, BASS or
TREBLE controls of Model SX-990, Adjust the
recording lwel whh the controls prwided on the
tape deck (or tape recorder).
NOTE; lf a monaural tape recorder is used, either
channel signal only can be reoded.
PLAYBACK
Turn on the TAPE MONITOR wvitch (14), and
adjust the VOLUME (11), BASS (7) and TREBLE
(8) controls for desired volume and tone.
o When the TAPE MONTTOR switch (141 is in the
"ON" position, the position to which the SELECT-
OR switch (5) is set is unrelated to the equipment
operation.
O MULTI-AMPLIFIER SYSTEM
A multi-amplifier system can be composed by using
a two- or threedivision band-pass filter and one or
two stereo power amplifiers besides Model SX-g90.
a) Remove the plugs which connect the pRE_AMp
output terminals (28) to the MAIN-AMP INPUT
terminals (291.
bl Connecr the pRE-AMP OUTPUT terminals to
the input terminals of the dividing band_pass
filter, and the MAIN-AMP INpUT terminals to
the output terminals of
band-pass filters.
cl Connect the input of
the other stereo pow-
er amplifiers to the
output terminals of
the other dividing
band-pass filters.
one of the dividing
TAPE MONITOR
When usinE a Shead tape deck (or tape recorder) for
repording, monitor can be conducted as follows:
o Turn on the TAPE MONITOR srvitch (14) and the
after-recording signal will be monitored.
3 Turn off the switch, and the before-recording signal
will be monitored.
Fis. t o
ERASE HEAD
RECORO HEAD PLAY BACK HEAD
TAPE RECORDING TERMINAL TAPE IV]ONITOR TERMINAL
iTAPE MON]
TAPE MONITOR
swtTcH LOUDSPEAKER
AS FOLLOWS
INTEGRATE STEREO SYSTEM
By connecting one or more of plONEER,s Model
distortion can be composed. Also, a pA system to be
used in a large place can be formed by using several
power systems wlth MoDEL sx-990.
&D STEREO SYSTEM
A 3-D stereo system can be produced by connecting
to the CENTER CHANNEL OUTPUT terminal (30i
a power amplifier equippd with a low-pass filter (f
= 150 to 250 Hz).
CENTER.CHANNEL LOUDSPEAKER SYSTEM
By connecting a power amplifir and loudspeaker to
thE CENTER CHANNEL OUTPUT brMirNI (30)
and placing the loudspeaker at the center between
the left and right channel loudspeakers, the ,,hole
effect'' of stereo sound can be prwented.
\roh
Fig. 17

SPECIFICATIONS
Transistors, lCs and Diodes
Tuner Section
Audio Section
Loudness Contour Switchable to ON-OFF, boost 12 dB at
50 Hz, boost 9 dB at 10 kHz, with
VOLUIVIE control set at -40 dB
FM Section
C i rcu itry Front end using an FET and 4-gang
variable capacitor, lF amplif ier 4 lC
Frequency Range 87.5 to 108 MHz
IHF Usable Sensitivity 1 7 /uv.
lmage Rejection 87 dB (at 98 MHz)
Signal to Noise Ratio 62 dB (lHF rating)
Antenna lnput 300 ohms (balanced)
Multiplex Section
Circuitry Time-switching type demodulator FM
Mono Stereo Automatic selection
Channel Separation 42 dB (at 1 kHz)
Audio Section
Circu itry Single ended push pull
Music Power output 8o 1o0 watts total (lHF rating)
+Q t go watts total
Continuous Power Outp11
(each channel driven) 35W/35W 80
Continuous Power Output 28W + 28W 8 O
(both channel driven) 3oW + 3oW 4Q
Harmonic Distortion Less than 0,5% (at 1 kHz rated output)
Frequency Response -t3 dB, from '10 Hz to 100k Hz (Overall)
Power Bandwidth 15 Hz to 40 kHz (AUX)
Hum & Noise MAG: better than 80 dB
(at rated output) AUX: better than 100 dB
lnputs lmpedance MAGnetic PHONO: 3.3 mv. 50 kO (1 kHz)
and Audio Sensitivity CERamic PHONO: 24 mv' lOO k O (1 kHz)
(for rated output) MlCrophone: 5 mv. 100 kO (1 kHz)
TAPE MONITOR: 20O mv. 100 kO (1 kHz)
AM Section
C i rcu itry
Frequency Range
I H F Usable.Sensitivity
lmage Reiection
Antenna I nput
S uperheterodyne
525 to 1605 kHz
18pV.
77 dB (at 1000 kHz)
Built-in Ferrite Loopstick Antenna
Output Terminals Speakers: 4 to 16 ohms
and jacks Stereo headphones jack. Simultaneous tape
recording iacks, equipped with TAPE
MONITOR switch' Tape recording/playback
jack (DlN standards)' Pre Output iacks,
Center Channel .iack'
Equalization Curves PHONO: RIAA
Tone Controls BASS: boost 1 1 dB, cut 16.5 dB (at 50 Hz)
TREBLE: boost 10 dB' cut 9.5 dB (at 10 kHz)
cut 8 dB (at 50 Hz)
cut 7.5 dB (at 10 kHz)
Power Supply, Etc.
Line Requirements 1'lO, 111 , 13O, 22O and 240 volts.
Dimensions
(switchable), 50 - 60 Hz
210VA, 19O watts (Max)
Overall .18" 1/16 459 mm (W)
5" 11116 145 mm (H)
14" 211 369 mm (D)
without package 25 lb.2 oz 1 1 .4 kg
with package 29 lb.2 oz 13-2 kg
AUXiliary:
MAIN lNput
LOW:
H IGH:
200 mv. 1O0 kO (1 kHz)
530 mv. 100 kC) (1 kHz)
Filters Weight

MALFUNCTION
CON DITIONS FREQU ENTLY M ISTAKEN FOR
Noise: There are a variety of noises relating to the operation of a
hi-fi unit. These are generally divided into two types; (1)the unir
is faulty (a transistor or part has deteriorated) and (2) an
external source of noise is adding noise to the unit.
When a hi-fi unit produces an unpleasant noise, it is often
assumed that the unit is faulty, but statistical records indicate
that the majority of noises produced in hi-fi acoustic units result
from external sources of noise. Due to the inherent high
sensitivity and the high fidelity in reproduction. the unit
amplifies and reproduces extraneous noises, however small, into
definite output noise. lf your receiver produces a noise, check
according to the following table and trace out the source of
noise for the appropriate corrective action.
Symptom Suspected Source of Noise Diagnosis and Remedy
a
o
!o
co
o
.E
c
a
.9
.J
c
o
3
=
Continous or intermittent
noise like jjjjjj or zzzzzz. . Static (lightning)
. Fluorescent lamp, motor, or thermostat
may be used in house or in the vicinity of
the house.
ln many cases, it is very diff icult to remove the source
of noise. ln order to make the radio input larger than
the noise level, set up a good outdoor antenna and
make a complete grounding.
When a station is tuned in.
hum is mixed in the pro-
gram.
. Poor fluorescent lamp, motor, or electric
heater may be used in house or near the
house.
Reversing the line plug may occasionally alleviate this
noise problem. Usually it is very difficult to eliminate
the noise.
Hissing sound noise in AM
(Medium wave) reception. o The frequency of an adjacent station is
interfering with that of the station being
tuned in (10kHz beat interference).
. TV set is on in the same house with the
recerver.
lmpossible to remove such interference. lf the cause of
such noise is in the TV set, increase the distance
between the TV set and receiver.
Static noise in FM recep-
tion (in particu lar, when
automobiles run close to
the house).
. White noise generated f rom automobile
engrnes.
r Radio frequency sewing machine or weld-
ing machine being used near your house.
ln an area surrounded by hills or high buildings, the
FM input signals are very weak. Thus the noise limiter
in the circuit loses its function. Set up an outdoor FM
antenna having many reflector elements.
Reception of FM stereo
program contains more
noise than FM mono pro-
gram.
a Note that the service area covered by an
FM stereo broadcast is about 50% of that
of a regular mono broadcast.
lncreasing FM input signal may alleviate this problem.
Use an exclusive FM outdoor antenna instead of the
indoor T-typeantenna.
!o
O
o
cc
o
.E
o
o-
c
o
t
=
Hum or buzz. When
switched to radio reception,
the noise disappears.
o Poor connection of shielded wire (a).
a Jack connection is loose. {b)
r Line cord or fluorescent lamp is near the
shielded wire. (c)
o Poor grounding. (d)
a HAM transmitting station or TV transmit.
ting station is near your house. (e)
Correct the conditions stated in (a), (b), (c) or (d). ln
case of (e), report it to an official activity.
Output tone quality is
poor and mixed with noise
Treble is not clear.
a Stylus is worn out. (a)
a Record is worn out. (b)
o Dust adheres to stylus. (c)
. Stylus is improperly mounted (d)
. Stylus pressure is not proper. (e)
. The TREBLE level is too high.
Check (a) through (e) and correct the condition.
Lower the TREBLE level.
Watch for the following conditions; these are also apt to be mistaken for malfunction.
Symptom Suspected Source of Noise Diagnosis and Remedy
Power is not turned on
although the power switch
is set to ON.
r Fuse is blown. (a)
o Line plug is loose. (b) Check (a) and (b) and correct the condition.
ln playing a record, in-
creasing the volume causes
howling
o Distance between the turntable and
speakers is too short.
o The place on which the turntable
speakers are set is unstable.
the
or
Change the distance or rearrange the installation
of the unit and speakers. (lnstalling theturntable
on a firm, solid stand may alleviate this ,problem.)
Do not increase the BASS sound level excessively.
14

I
ALIGNMENT INSTRUCTIONS
ALIGNMENT OF FM SECTION
Disconnect OUTPUT terminal of front end from lN terminal of lF unit
Position of Switch: SELECTOR ....... FM MONO
MUTTNG ......... OFF
Volume Control Setting: Fully Counterclockwise
STEPS
I nput
Level Dial
Setting
Output
Equipment
Connections
Alignment
Equipment
Connections Frequency Adiust Remarks
Sweep Generator
lN terminal
of lF unit 10.7MHz
40dB Oscilloscooe
@
terminal
Tl of lF Unit
f2
T3
Adjust for maximum
sensitivity and symme-
trical characteristics
280dB Check symmetry of curve
3Remove electrolytic capacitor C12 (of FM lF Un 4.71tFl in detector circuit
4Sweep Generator
lN terminal
of lF unit 10.7MHz 40dB Oscilloscope
OUT terminal Ta of
lF Unit
Adjust the primary core
of T4 so that slope of
straight portion of "S"
curve will become the
steepest and adlust the
secondary core so that
the center of "S" curve
will concide with the
center of the marker.
5Connect OUTPUT terminal of fronted to lN terminal of lF unit
6Sweep Generator
TP of Front-
end 10.7MHz
40dB Point of
no inter-
ference as
near as
88MHz
Oscilloscope
@
terminal
T2 of
frontend
Adjust for maximum
sensitivity and symme-
trical characteristics
780dB Check symmetry of curve
840dB Oscilloscope
OUT terminal Ta ot
lF Unit Adj ust similarly to
STEP 4.
IConnect electrolytic capacitor Cn l4.7ltFl
10 Signal Generator
FM Antenna
terminal
9OMHz 2odB
(400H2
300/ol
90MHz Oscilloscope
V.T.V.M.
OUT terminal
L5 of
frontend Adjust for maximum
deflection
't1 106MHz 106MHz CTa of
frontend
12 Repeat STEPS 10 and 1several times
13 Signal Generator
FM Antenna
terminal
90MHz 1odB
(400H2
307o)
90MHz Oscilloscope
V.T.V.M.
OUT terminal
Lr, Tr,
T2 of
frontend Adjust for maximum
def lection
14 1O6MHz 106MHz CT1, CT2,
CT3 of
frontend
15 Repeat STEPS 13 and 1several times

ALIGNMENT OF MPX SECTION
Position of Switch: SELECTOR FM AUTO
MUTING OFF
Volume Control Setting: Fully Counterclockwise
lnput Signat : Main (L+R) 4O.SKHz Deviation (60%)
l9KHz Pilot 7.5KHz Deviation (lOo%)
ALIGNMENT OF AM SECTION
Position of Switch: SELECTOR ......... AM
Volume Control Setting: Fully Counterclockwise
STEpS ] Circuit to be Alignment
MPX SG to FM
Antenna
terminal
Adlust for maximum def lection.
Adjust for minimum deflectjon of the other
ch annel,
Point of no
interference
as near as
535KHz
T3 , Ta, T5 Adjust for maximum
sensitivity and symme-
trical characteristics
Repeat STEPS 2 and 3 several times
Signal Generator
Antenna terminal
through dummy AC V,T.V,M.
OUT terminal Adjust for maximum
deflection
cTr, cT2
Repeat STEPS 5 and 6 several times

PARTS
TOP VIEW
ouT :ro F€rt€ Loopstrck Antenn.
IVAIN AMP SHIELD CASE
.60
03 tlz oll
o N 2SC460
OIN, AM TUNER UNIT
c64 030
OIN, AM TUNER UNIT
oL\D o I o-ooe (-l ,\oo o v
FR O N'I FM
END
NPUT SELECTOR
51 3 029
MO
LM703L
oLg-l
EO
o o oMUr
atroaa arro:,
Or -r 02
O LgJO
703L
tRl
BOTTOM VIEW
oo
A ""ril", o', f)
^ V ' 2SCBToV-
!a! Ua,
2SC87l 2SC87l
E83
n_
t\a4qav 02 O2l I
n 2 oo+\9 Ll
bl , g,'[ !i"o'u
0r oj
2 SC4 58
'o
FI,4 FRONT END
PUSH
SW TCH
UNIT
H GHCUT FI LTER

PARTS LIST
CAPACIT()RS
lN pF, IO2ZTOLERANCE UNLESS OTHERWTSE NOTED
P:ppF
Symbol Descri pti on Part No
Ct
C2
Ca
C4
C5
U6
C7
C8
Ce
Cro
Ce rami c
EI ectrol yt
Myl ar
El ectrol yt
Ceramic
Ceramic
Ceramic
Myl ar
l\4ylar
Ceramic
Vailable capac
for AM tuner
c
c
Unit
3P
220
0 0015
2200
001
001
001
0 001
0 001
004
+0 5P
+ ao"Z
+200.4
1 AOaZ
20"2
+ 80t.
2Oa,r
50v
50v
80v
DC 1 4KV
DCI 4KV
DCl4l(V
50v
50v
50v
152 085 0
c43.003.c
c43.003.0
c43 003-0
CKDYZ4O3Z5O
c64 030 0
RtstsT0Rs
IN OHM |OAZ TOLERANCE, AZW UNLESS OTHERWISE
NOTED K:KO, M:MO
MI SCE LLANE t) US
Symbol Descilptton Part No
Pot
FM FRONT END
FM lF Unit
N4PX Unit
AN4 TUNER Unit
MUTING Unit
INDICATOR Unit
HEAD Amp Unit
CONTROL Amp Unit
CONTROL Unit
PUSH Switch Unit (A)
PUSH Switch Unit (B)
MAIN Amp Unit
POWER SUPPLY Unit
Front Panel
Diat Putley
Foot
Wooden Case
Dial Glass
Dial Pointer
Tuning lVerer (lower)
Tuning lVeter (Upper)
Knob, Setector
Knob Tuning
Knob, Speakers, Volume, Balance, lvode
Knob, Bass, Treble (L)
Knob, Bass, Treble (R)
6P input Terminal
4P Input Terminal
1P Input Terminal
4P Antenna Terminal
Pilot Lamp (for Dial Glass)
Lamp (ior Selector Position, FM Stere0 tndicat0r)
Pilor Lamp r f or Tuning Meter.l
Fuse 1A
Socket tor AC OUTLET
Jack for Speaker
Jack for lVicrophone
Jack for Headphone
Pilot Lamp Socket
Fuse Holder 1p
Uonnector 5P
w l I .028.(
w12 032 L
w13.026 (
w14 008_c
\,v18 026 (
w 18- 012.C
try 1 5.049.t
w15.079 C
!v 1 5.080.c
w15-081 A
\,ry15-082-C
\iv l 5 -060.8
w16.022.c
l\421-323 c
M42 027.A
iv61,017.0
t\452- 119 D
A33.084.A
431-090-C
491.009,D
A91.008 D
A 12.163 0
A 12. 165.0
A12.120.8
A 1 2, 168-0
A 12,016.O
K22.0r3-C
K21,010 E
K2l 005-c
K l1 -018-0
E22.011.O
E22.021-O
E22-002.O
Symbol Desclptton Part No
R1
R2
R3
R4
R5
R6
R7
R8
Re
Rlo
Ru
Rt2
Rt3
Rr+
R15
R16
RL7
Rls
Ca rbon
Ca rb on
Ca rbon
Ca rbon
Carbon
Carbon
Ca rbon
Carbon
Ca rbon
Carbon
Ca rbon
Carbon
Carbon
Carbon
Carbon
Carbon
Carbon
Carbon
REC
ilm
ilm
rlm
ilm
ilm
ilm
ilm
ilm
ilm
ilm
ilm
ilm
ilm
ilm
ilm
ilm
ilm
ilm
150K
1 50K
100K
100K
1 t\4
1 l\,1
68K
68K
470
470
150
150
68K
68K
1M
470
68K
68K
3W
3W
w52.M4.O
Ct)ILS AIID TRAI'ISFtlRMERS
Symbol Descri ptl on Part No
Power Transformer
l\4atching Transf ormer
l\y'atching Transf ormer
AIV Ferrite Loopstick Antenna
Heater Choke Coil
Choke Coil
T52 158 (
T61.041 E
T61.041 E
r42.024 I
T 24.026.(
T24 030-C
SWITCHES
Symb ol Descriptiorr Part No
Sr
S2
S3
SELECTOR Switch
IVODE Switch
SPEAKERS Switch
LINE VOLTAGE Selector
S
S
S
S
3 029,(
4 035.(
I-022 I
1.018 (
P(]TE N TI t] ME TE RS
Symbol Description Part No
VRI
VR2 500K0 dual, VOLUIVE
500K0 dual, BALANCE c85.054 (
c85 048 (
IB

Fil FRtllrT Elro (Wr r-028)
CAPACIT(lRS FM rF UNtT (W12-032)
CAPACITORS
Symbol Descri pti on Part No
C1
C4
C5
C6
C7
C8
c9
Clo
Clt
C12
C13
Ct4
Cl5
C16
C17
cls
C19
C20
CVI
CV2
CV3
CV4
CTI
Cf2
cT3
CTa
Ceramic
Ceramic
Cera mi c
Cerami c
Cerami c
Cerami c
Cerami c
Cerami c
Ceramic
Cerami c
Ceramic
Ceramic
Cerami c
Ceramic
cerami c
Cerami c
Cerami c
Cerami c
Cerami c
Vri abl e
Capaci tor
for Fl\,1
tuner unit
( 4gang,)
Cylinder trimmer
0 001
6P
10P
10P
10P
5P
1P
001
5P
5P
7P
+ IOOoZ
-o
+o 25P
+0 5P
+0 5P
+0 5P
+0 5P
+l oooz
o
+0 5P
+0 5P
+0 5P
25V
50v
50v
50v
50v
50v
25V
50v
50v
50v
c47-005
c47.005
c47.co{.C
c43-002.c
c47.005.F
c47-005./
c64.036.E
c47,005.1
c47.O05.t
c64.036.
c64.036
c64.036
c64.036
c64.036
c64.036
c64.036
c45-004
Symbol Description Part No
c1
c2
c3
c4
c5
c6
c7
c8
c9
c10
c11
c12
cl3
c14
cl5
c16
c17
c18
cl9
c20
c21
c22
c23
Ceramic 0.01 50V
Ceramic 0 01 50V
Ceramic 0.01 50V
Ceramic 0.01 50V
Ceramic lOP 50V
Mylar 0.1 50V
Ceramic l OP 50V
Ceramic 0.01 50V
Ceramic O 01 50V
Ceramic 1OP 50V
Ceramic 0 01 50V
Ceramic 0.01 sOV
Ceramic 3P 5OV
Electrolytic 1 5OV
Ceramic 0.01 5OV
Ceramic 0.01 50V
Ceramic 10OP 50V
Ceramic 0.01 50V
Ceramic 0.01 5OV
Electrolytic 4.7 1 6V
Ceramic 1O0P 50V
Electrolytic 4.7 l6V
Eltrtrolytic 1 25V
CKDYZ 103P 50
CKDYZ 103P 50
CKDYZ 103P 50
CKDYZ 103P 50
ccDSL '100K 50
coMA 104K 50
ccDSL 100K 50
CKDYZ 1O3P 50
CKDYZ 103P 50
ccDSL 100K 50
CKDYZ 103P 50
CKDYZ 103P 50
ccDSL 030c 50
CEMX IMF sOV
CKDYZ 1O3P 50
cKoYZ 103P 50
CCDSL 101K 50
CKDYZ 103P 50
CKDYZ 103P 50
CEMX 4R7MF 16\
ccDSL 101 K 50
CEMX 4R7MF ,I6\
CSYA IMF 25V
RE SIST()RS
Symbol Descri pti on Part No,
R1
R2
R3
R4
R5
R6
R7
R8
R9
Rlo
Rll
Rl2
R13
Carbon
Carbon
Carbon
Carbon
Carbon
Carbon
Carbon
Carbon
Carbon
Carbon
Carbon
Carbon
Carbon
lm
lm
lm
lm
lm
lm
lm
lm
lm
lm
lm
lm
lm
100K
1M
220
39K
22K
1K
220
8.2K
22K
15K
22K
22K
3.3K
%w
%w
%w
%w
%w
%w
%w
%w
%w
%w
%w
%w
%w
RESISTORS
Symbol Descr ipt io nPart No.
R1
R2
R3
R4
R5
R6
R7
R8
R9
R10
R11
Rl2
R13
R14
R15
R16
Carbon film 820
Carbon film 10K
Carbon film 47K
Carbon film 100
Carbon film 1K
Carbbn film 47K
Carbon f ilm 1K
Carbon film 47K
Carbon film 100
Carbon film 18K
Carbon film 2.7K
Carbon film 22K
Carbon film 10O
Carbon film 22K
Carbon film 22OK
Carbon film 820
RFy.PS 820.K
RF7.PS 1OK-K
RF7.PS 47K.K
RF%PS lOO.K
RF%PS 1K-K
RF%PS 47K.K
RF%PS 1K-K
RF74PS 47K-K
RF%PS lOO-K
RF%PS 18K.K
RF%PS 2R7K.K
RF%PS 22K.K
RF%PS 1OO.K
RF%PS 22K-K
RF%PS 22OK-K
RF%PS 820-K
C()ILS AIID TRAI{SFtlRMERS
Symbo Descri pt i on Part No.
TI
I2
L1
L2
L3
L4
L5
FM Antenna Coil
Flr4 lF Transtormer
RF coil
RF coil
RF choke coil
RF choke coil
OSC Coil
T22-Ot3.t
r73.020.(
T21.013-r
T23.026.t
r24.028.(
r24.028.(
r23.O32.t
SEMICONDUCTORS
Symbol Description Part No.
D1
D2
D3
D4
D5
D6
o1
02
o3
o4
1S188 FM-1 or 1N60 Diode
15188 FM-1 or 1N60 Diode
1S188 FM-1 or 1N60 Diode
1S188 FM-1 or 1N60 Diode
1S188 FM-1 or 1N60 Diode
1S188 FM-1 or 1N60 Diode
TA7O60P-R or W lC
TA7060P-R or W lC
TA7060P-W rC
TA7060P-W tC
D I tlDE A1{t) TRAI{SIST(lRS
Symbol Descri pti on Part No.
Qr
Qz
Qs
D1
25K22-\ FEr
2SC46l @ Transistor
2SC451 @ Transistor
1S85 Variable Capacitance Diode
t19

COILS AND TRANSFORMERS
Symbol Description Part No.
L1
t2
T1
T2
T3
T4
RF Choke Coil
R F Choke Coil
FM lF Transformer
FM lF Transformer
FM lF Transformer
FM lF Transformer
T24-O2A-A
T24-O2A-A
T73-041-O
T73-041-O
T73-041-O
T74-O14-O
COMPOUND PART