Pioneer SX-1250 User manual

AM
/FM STEREORECEIVER
sx-l?50
<ART,158-0>
77i <, "
- ^-C r
lif
f
' rl
(v)proNEER

Type Voltage Remarks
KCU 120Vonly CSA {Canada}
and UL {U.S.A) approved
with de'emphasisselector switch (25psl75ps)
HG 22OV and24OV (Switchable) SEMKO
{Sweden),
NEMKO
(Norwav),
DEMKO
(Denmark)
and
El (Finland)
approv€d
s1IOV, 12OV,22OV and240V {Switchable) Generalexport modelwith de-emphasisselector
switch{25pslsops/75psl
MODELSX.125O
COMES
IN
THREEVERSIONSDISTINGUISHED
ASFOLLOWS:
Whenrepairing
Sor HGtype,
please
see
the
manualonpage
101.
CONTENTS
SPECIFICATIONS
FRONTPANEL
FACILITIES
CONNECTION
DIAGRAM
CIFCUITDESCRIPTIONS
4,1 TunerSection
4.2 AudioSection
5.
6.
7.
8.
4.3 Protection
Circuit
. .......,. 17
4.4 Power
Supply
Circuit ....... 18
LEVEL
DIAGRAM
.,.. ......... 19
BLOCKDfAGRAM
....
. ....... 20
DlsAssEMBLY. ........22
PARTS
LOCATION
8.1 Front
Panel
View.. ........ 25
4.2 RearPanel
View .........,27
8.3 TopView ........29
8.4 Bottom
View ....., 31
8.5 Front
View .......33
ADJUSTMENTS
9.1 AMTuner ... . 3b
9.2 FM
Tuner ...........36
9.3 Power
Amplifier ...........38
9.4 Stabilizer ... .. ..... 38
DIALCORDSTRINGING ........ 39
EXPLODED
VIEWS
. ... . 40
SCHEMATICDIAGRAMS,
P.C.
BOARDPATTERNS
AND
PARTS
LISTS
1.
2.
3.
4.
4
6
I
11
14
9. Ii
I
10.
11.
12.
51
12.1 Miscellaneous-parts
I
I

'--
\o 12.2
12.3
12.4
12.5
12.6
12.7
12.8
12.9
12.10
12.11
12.12
12.13
12.14
12.15
12.16
12.17
12.18
sx-1 25C,
SchematicDiagram
Internal
Circuitryof Integrated
Circuits
The
Circuitof FMFrontEnd
(AWB-023)
Tuner
Assembly
(AWE-0681
De+mphasis
Switch
Assembty
(AWX-099)
Equalizer
Amplifier
Assembly
(AWF-021
)
Function
SwitchAssembly
(AWS-094)
FlatAmplifier Assembly
(AWG-042)
5PConnector
Assembly
(AWX-062)
ControlAmplifierAssembly
(AWG-0411
FilterAmplif
ierAssembly
(AWM-089)
Microphone
Jack
Assembly
(AWX-@71
Pourer
AmplifierAssembly
(AWH-048)
Speakers
SwitchAssembly
(AWS-G}S)
Protection
CircuitAssembly
(AWM-091)
Stabilizer
Assembly
(AWR-l
06)
Power
Supply
Assembly
(AWR-I07)
PACKING
PARTS
LIST
OF
EXPLODED
VIEWS
.
SUPPLEMENTS
FOR
SX-l250/HG
ANDSX-1250/5
15.1 Contrast
ofMiscellaneous-parts
.. ........101
15.2 Schematic
Diagramfor
SX-1250/S .....lO3
15.3 SchematicDiagram
forSX-l2sOlHG. ..... lOb
15.4 De-emphasis
SwitchAssembly
(AWX-101,
for
S
type) .. .....1O7
15.5 Speakers
SwitchAssembly
(AWS.098,
for
HGtype) ........ 108
15.6 Poriver
SupplyAssembly
(AWR-108,
for
HGtype) .........110
s3
55
56
57
63
64
68
70
75
76
80
83
84
88
90
93
96
98
99
13.
14.
15.
I
a
!

F
1.SPECIFICATIONS
Semiconductors
FETS.... ...... 5
|Cs..... ......6
Transistors ......82
Diodes
.. ......60
PowerAmplifierSection
C.ontinuous
PowerOutputfrom 20 Hertz
to 20,000
Hertz
(Both
channels
driven).. 160
watts
per
channel
(8
ohms)
200watts
Per
channel
(4ohms)
Total
HarmonicDistortion
(20
Hertzto 20,000Hertz,
from
AUX)
ContinuousRated
PowerOutput.. . Nomorethan0.1%
80
watts
per
channel
power
output,
8ohms . . . Nomorethan0.05%
1watt
per
channel
power
output,8ohms . . . Nomorethan
O.O7%
Intermodulation
Distortion
(50
Hertz: 7,000Hertz
=
4: l,
fromAUX)
Continuous
RatedPower
Output.. . No morethan
0 1%
80
watt!
per
channel
power
output,8
ohms . . . Nomorethan
0.05%
1watt
per
channel
power
output,Sohms . . Nomore
than
0.O1%
FrequencyResponse
. .. ... . . .5H2to
100,000H2ildB
InputSensitivity/
|
mpedan
ce
POWER
Ar\4P
|N.........
Output
Speaker..
Headphone
DampingFactor
.......1V/50kohms
.
A, B,C,A+8, B+C,A+C
...... Lowlmpedance
(20H2
to
20,000H2,8
ohms). .......30
HumandNoise
(lHF,
short-;ircuited,
A Network)
. .100d8
Preamplif
ierSection
InputSensitivity/
lmpedance
PHONOI
PHONO
2
t\4tc....
AUX,..,
TAPEPLAYI.....,
TAPLPLAY2......
TAPEPLAY
2 (DlN conne(lor).
. .
PHONOOverload
Level
(T.H.D.
0.1%)
PHONO
I
PHONO
2
OutputLevel/l
mpedance
TAPL
RECI ...,.
,
TAPERLC2......
TAPE
REC2(DlN connector)
.. .
PRE
OUT
Totallllrmonic
Distortion
(20Hr
ot 20,000Hr,
IV ourpur) . . Nomore
thanO.02%
Frcquency
Rcsponse
PHONO
{R
IAAequ,rlizrrion).
.30}12
ro15,000H2r0.2dB
AUX,TAPE
PLAY
....... tOHzto50,000H.,lldB
ToneControl
BASS...
I'REBLE
.
Filter
LOW....
lV/1k
ohms
80dB
74dB
0.1%
HIGH
,..
Loudness
Contour
(Volume
control
set
at 40dB
position)
. . . . .+6dB
(100H2),+3dB
(t
okHz)
Hum and Noise (lHF, short,circuited,
A Network, rated
power)
PHONO........
AUX,
TAPE
PLAY
l\4uting
..
FM Section
Usable
Sensitivity.. . l\40No
..
STEREO..
Usable
Sensitivity
(lHF'58)
.....
50dB
Quieting
Sensitivity....
l\40No . . .
STEREO..
Signal-to-Noise
Ratio at65dBf . .
Distortion
at65dBfl00Hz.....
lkHz. . . . . .
6kHz
.
. . [4AlN 1l0dB (l00Hz)
SUB t sdB(s0Hz)
. . l\4AlN 1'l0dB (tokHz)
SUB t 5dB
(20kHz)
.. 30Hz
(12dB/oct.)
. . 8kHz
(12dB/oct.)
... 75dB
...90dB
. . 20dB
8.7dBf
(3.orv/300s})
la.sdBf
(s.8gV/300[l)
. . 1.5irV
11.sdBf
(a.1pV/3000)
36.0dBf
(69sV/300())
MONO.......
STEREO.....
i\40No......
STEREO....
MONO......
STEREO....
.
0.25%
.0.1%
. 0.2/o
. 2.5mV/50k
ohms
. 2.5mV/50kohms
. 6.5mV/50k
ohms
.150mV/50k
ohms
.150mV/50k
ohms
. I50mv/50k
ohms
.150mV/50k
ohms
. . 500mV
(1
kHz)
. . s00mV
(1kHz)
........150mV
........150mV
. 30mV/80k ohms
Frequency
Response
...l\40No....... 0.3%
STEREO.. . .. O.3Vo
. . 30Hztol5,000Hri?
3dB
Capture
Ratio ..........l.OdB
AlternatcChannelSelectivity ........ 83dB
Spurious
Response
Ratio... .......11OdB
lmage
Rcsponse
Ratio
... .........110d8
lF
Response
Ratio
... ...120d8
AMSuppression
Ratio... .........60d8
/VlutingThreshold .....13dBf(4.9pvl3004)
Stereo
Separation
. . 50dB (lkHz),
35dB
(30H2-t5kHz)
SubcarrierProductRatio .......... 14dB
SCARejection
Ratio... ..........74d8
AntennaInput 300ohms
balanced
75
ohmsunbalanced
I
.
I
I
s
I

six-1 Elscl
A\,?
AM Section
Scnsitivity
(lHF,
Ferritcantenna)
(lll
F,Ext.antenna)
Sclcctivity
Signal-to-Noise
Ratio
........
lmage
Rcsponse
Ratio.......
lFRcsponse
Ratio.. .
Antenna
..
l\4iscellaneous
PowerRcquircmcnts ... 120V
60HZ
.......6s0w(uL,csA)
'1200W
(max.)
Powcr
Consumption
Dimensions........
556(W)x186.5(H)
x464.5(D)
mm
21-7l8(w)
x7.3/8(H)
x 181/4(D)
in
Weight
Without
Packag€
. . 29.2kg(641b
4 oz)
WithPackage ..... 33.2kg
(73
lb1oz)
.
Built'inFcrrite
......300pV/m
.........l5irv
.........40d8
.........55d8
.........65dB
.........85dB
Loopstick
Antenna
Furn
ished
Parts
Fl\4
T-typc
Antcnnd
. .
Opcrating
Instructions
Hex.
Wrench
.1
,1
.t
NOTE:
Specifications
ond thedesigtr
subject
to possible
modifica.
tion uithout noticedue to improuements.
sHEX WRENCH
The accessoryHex. wrenchis provided
for removingthe
VOLUME and TUNING knobs, or for tightening its
setscrewin theeventit becomesloose.
If required,loosenthe setscrew
by insertingthe wrench
into the hole on the side of the knob and tuming the
wrench counterclockwise. Be particularly careful not to
scratch
the front panel whenemploying
the wrench.
5