Sony STR-232L User manual

GENERAL
Power Requirements:
Power Consumption:
Dimensions:
Weight:
FM SECTION
Tuning Range:
Antenna:
Intermediate
Frequency:
Sensitivity at
50d8 Quieting:
SPECIFICATIONS
240 V ac, 50 Hz (UK model)
120 V, 220 V or 240 V ac adjustable,
50 Hz (AEP model)
110 W (UK model)
95 W (AEP model)
Approx. 410 (w) x 145 (h) x 305 (d) mm
16 (w) x 5 % (h) x 12 (d) inches
including projecting parts and controls.
5.9 kg, 13 Ib (net)
Approx. 7.1 kg, 15 1b 11 oz {in shipping carton)
87.5 — 108 MHz
300 2 balanced
75 2 unbalanced
10.7 MHz
4 nV (12 dB) (MONO)
45 nV (33 dB) (STEREO)
Sensitivity at
46dB Quieting:
(at 40kHz deviation)
Usable Sensitivity:
S/N Ratio:
Harmonic Distortion:
IM Distortion:
Separation:
Frequency Response:
AEP Model
UK Model
FM
STEREO/FM-AM.
RECEIVER
4.5 uV (13 dB) (MONO)
50 uV (34 dB) (STEREO)
1.9 nV (5.5 dB), tHE
1.7 nV (4.5 dB), S/N = 26 dB
(40 kHz deviation)
73 dB (MONO)
68 dB (STEREO)
At 1 kHz
0.3 % (MONO)
0.5 % (STEREO)
0.3 % (MONO)
0.5 % (STEREO)
45 dB at 1 kHz
40 — 12,500 Hz *°:
+0.
30 — 15,000 Hz “>
— Continued on page 2 —
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY SHADING AND MARK
A ON THE SCHEMATIC DIAGRAMS, EXPLODED
VIEWS AND IN THE PARTS LIST ARE CRITICAL TO
SAFE OPERATION. REPLACE THESE COMPONENTS
WITH SONY PARTS WHOSE PART NUMBERS APPEAR
AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS
PUBLISHED BY SONY.
®
SERVICE MANUAL

| STR-232L
Selectivity:
Capture Ratio:
AM Suppression Ratio:
Image Response Ratio:
Spurious Response Ratio:
Muting Threshold:
MW/LW_ SECTION
Tuning Range:
Antenna:
Intermediate Frequency:
Usable Sensitivity:
S/N Ratio:
Harmonic Distortion:
Selectivity:
55 dB (300 kHz, S/N = 26 dB, 40 kHz
deviation)
1.0 dB
54 dB
45 dB
75 dB
Approx. 5 V
MW: .530 — 1,605 kHz
LW: 150 ~~ 350 kHz
MW: External antenna terminal
Built-in ferrite-rod antenna
LW: External antenna terminal:
Built-in ferrite-rod antenna
468 kHz
MW: 250 uV/m (40 dB/m),
built-in antenna (1,000 kHz)
LW: 500 uV/m (53.8 dB/m),
built-in antenna (230 kHz)
100 nV (40 dB),
external antenna (230 kHz)
MW: 52 dB at 5 mV
LW: 52dBat5mvV
MW: 0.3 % at 5 mV, 400 Hz
LW: 0.3 % at 5 mV, 400 Hz
28 dB (9 kHz)
AUDIO AMPLIFIER SECTION
Continuous RMS Power
Output:
Less than 0.7 % THD, both channels
driven simultaneously
At 40 — 20,000 Hz
18 W + 18 W (8 2)
At 1 kHz
20 W + 20 W (8 Q)
According to DIN 45500
20 W + 20 W (8 2)
@® MODEL IDENTIFICATION
— Voitage Selector —
Only in AEP models, the voltage selectors are installed.
Po, ee
IHF constant power supply method
56 Wat 82
10 — 40,000 Hz, IHF
20 at 1 kHz (8 2)
Less than 0,7 % at rated output
Less than 0.3 % at 1 W output
Less than 0.7 % at rated output
Less than 0.3 % at 1 W output
Less than 0.08 pW at 8 2
PHONO:
RIAA equalization curve + 1.0 dB
TAPE:
10 — 50,000 Hz
Dynamic Power Output:
Power Bandwidth:
Damping Factor:
Harmonic Distortion:
IM Distortion:
(60Hz : 7kHz=4: 1)
Residual Noise:
Frequency Response:
+1dB
—3 dB
Inputs:
Impedance | S/N Weighting
network
50k2 |70dB A
100k2 |90dB A
Measured with rated output power into 8 2 loads
{both channels driven simultaneously) at 1 kHz.
Sensitivity
PHONO | 2.5 mV (—50 dB)
TAPE 150 mV (—14.5 dB)
Outputs:
(with rated input)
Voltage Impedance
REC OUT | 150mV(-14.54B) | 10k2 :
Headphones: Accepts all low or high impedance
headphones.
Speaker: 8 — 16 2 speakers are suitable.
BASS: +8 dB at 100 Hz
TREBLE: +8 dB at 10 kHz
+8 dB at 100 Hz
+3 dB at 10 kHz
Tone Controls:
Loudness Control:
(att. 30dB)
0dB=0.775 V

SECTION 1
OUTLINE
1-1. BLOCK DIAGRAM
FM
T™901 FRONT-END BLOCK
ANTENNA oe see = =
PRE AMP) AMIE AMP/ AM DE
AMP FM MIX 6 AM OSC/AM MIX
|
(iH) - ! FW OSC
| chia OY
[uw]—-
L———~——————-— 4 me901 [SIGNAL
MW/LW FERRITE-ROD ANT
™
a8 aA 1201
SII
; L204
ose
ll L209 m~ yf
i gee]
: I
EXT =
Ekisal L206 = |LW
ANTENNA Lw Osc $1-5
f BUILT L_LW 4
ef €
SI
L205
$2-2
FUNCTION
5902 EQ AMP :
[PHONO] © 9501,502 >|
VOLUME
(7)
3904 PHONO
p POWER AMP
REC wT] O TUNER (8) @)
Tere on 6! Bore
$2-3
1903 & MONO S4-1
; LOUDNESS
STEREO
R~CH cai TREBLE
[MoDE}
B+
POWER
AMP
B+
EQ AMP AC IN
D701,708
B+
TUNER
(4)
db
STR-232L STR-232L
MPX (2)
1C 301 (1) R~CH
L-CH twg02
SPEAKER
R-CH
3901
HEADPHONES

| STR-232L STR-232L
SECTION 2
DISASSEMBLY
@ Follow the disassembly procedure in the numerical order
given.
IC REPLACEMENT
CASE
REMOVAL
DIAL
CORD
STRINGING
® See page 7.
Fd
~) TA, P3 x 8
FRONT GLASS REMOVAL
rear panel
glass support side chassis (L)
front glass
glass support
heat sink
BOTTOM PLATE REMOVAL
FRONT PANEL REMOVAL
IC bracket
C651
insulator
+)
front panel
BVTT3x6
main circuit board
Retainer : Y Ww?
bottom plate
insulator Unsolder the pins of 1C601, 651.
IC bracket
Pull out all knobs.
—5-
~6—

STR-232L
oO)
DIAL CORD STRINGING
1) Preparation
ioe)
jo)
N
dial cord, 0.6mm dia.
661mm
~
(26 % inches}
2) Stringing
@ Turn the dial drum fully clockwise.
o ©
0
f
wo
es
° +
© three turns”
ise)
Gial drum
lo N
3) Dial Pointer Installation
1. Tune the receiver to the off-the-air signal.
2. Set the dial pointer to the frequency of the dial scale $2 =
and install it. [ £
Oo Qo

STR-232L
3-1. | MW SECTION
Setting: FUNCTION Selector:
Band Selector:
MODE Selector:
AM rf signal
generator
WA
In
Modulation: 400 Hz, 30 %
SECTION 3
ADJUSTMENTS
TUNER
MW
STEREO/FM-AM MUTE
Put the lead-wire
antenna close to
the set.
———
VOM
(range: 0.5—5V ac]
REC OUT
e Repeat the procedures in each adjustment
several times, and the frequency coverage
and tracking adjustments should be finally
done by the trimmer capacitors.
MW TRACKING ADJUSTMENT
Adjust for a maximum reading
on VOM.
L201
CT203
600 kHz
1400 kHz
MW FREQUENCY
COVERAGE ADJUSTMENT
Adjust for a maximum reading
on VOM.
CT201 1680 kHz
L204 520 kHz
AM IF ALIGNMENT
Adjust for a maximum reading
on VOM.
CFT201

STR-232L
3-2. | LW SECTION
Setting: FUNCTION Selector: TUNER
Band Selector: LW
MODE Selector: STEREO/FM-AM MUTE
LW ANTENNA Selector: BUILT IN
AM
rf
signal
VOM
generator frange: 0.5—5V ac}
Put the lead-wire
antenna close to
the set.
G set 7.)
Modulation: 400 Hz, 30 %
REC OUT
é
e Repeat the procedures in each adjustment
several times, and the frequency coverage
and tracking adjustments should be finally
done by the trimmer capacitors.
LW EXT ANTENNA COIL ADJUSTMENT
AM
rf
signal
LW
dummy
antenna
generator
Carrier frequency: 230 kHz
30% amplitude modulation LW ANTENNA terminal
by 400 Hz signal
1. Set the ANTENNA LW switch to EXT position.
2. Tune the set to 230 kHz and adjust L205 for a maximum
reading on VOM.
£205
“s. L209
CT204 .
170 kHz
310 kHz
LW FREQUENCY
COVERAGE ADJUSTMENT
Adjust for a maximum reading
on VOM.
CT202
L206
365 kHz
145 kHz

| STR-232L
3-3. | FM SECTION
Setting: FUNCTION Selector: TUNER
Band Selector: FM
MODE Selector: STEREO/FM-AM MUTE
VOM
frange: 0.5—5V ac}
FM ff signal
generator
FM ANTENNA
O 10 pF ‘terminal 7§Q. —_——
a REC OUT
x
e@ Repeat the procedures in each adjustment
several times, and the frequency coverage and
7 tracking adjustments should be finally done
by the trimmer capacitors.
Modulation: 400 Hz, 40 kHz deviation (100 %)
FM FREQUENCYC
COVERAGE ADJUSTMENT
Adjust for a maximum reading
on VOM.
87.1 MHz (87.5 MHz)
108.5 MHz (108 MHz)
( ): in West Germany
FM TRACKING ADJUSTMENT
Adjust for a maximum reading
on VOM.
L2 87.1 MHz (87.5 MHz)
_ 108.5 MHz
(108 MHz)
( _ ): in West Germany
abr

STR-232L STR-232L
FM
DISCRIMINATOR
ALIGNMENT
1
Setting:
FUNCTION
Selector:
TUNER
Band
Selector:
FM
FM
DISCRIMINATOR
ALIGNMENT
2
MODE
Selector:
MONO
TUNING:
Detuned
position
VOM
Setting:
FUNCTION
Selector:
TUNER
(range:
2.5V
de)
Band Selector: FM
MODE
Selector:
MONO
:
Procedure:
FM
stereo
T.P
2
‘
:
signal
;
dswiniog
a
7
Adjust
the
blue
core
(primary-side)
of
IFT201
for
generator
meter
0
V
reading
on
VOM.
Note: When replacing the ceramic filter (CF201), perform
this alignment.
1FT201
(primary
side; blue)
FM ANTENNA
75 Q
REC OUT
Carrier
frequericy:
98
MHz
FM
IF
ALIGNMENT
Setting:
FUNCTION
Selector:
TUNER
Output
level:
1
mV
(60
dB}
<
Modulation:
400
Hz,
40
kHz
deviation
.
.
Band
Selector:
FM
(100
%)
FM
signal
MODE
Selector:
MONO
Procedure:
generator
VOM
Adjust
the
black
core
(secondary
side)
of
IFT201
for
minimum
distortion.
FM STEREO SEPARATION ADJUSTMENT
Setting: FUNCTION Selector: TUNER
Band
Selector:
FM
1FT201
P
dary
side:
black)
a
MODE
Selector:
STEREO/FM-AM
MUTE
fracondary:
<i
FM
ANTENNA
REC
OUT
Brooeaane:
stereo
signal
.
. .
VOM.
Generator
VTVM
Carries
Freqency:°
83
Milz
Adjust
IFT1
for
maximum
reading
on
the
VOM
Output
level:
12.5
pV
(22
dB)
0.01
uF
Modulation:
400
Hz,
40
kHz
deviation
(100
%)
FM ANTENNA REC OUT
762.
p
19kHz
ADJUSTMENT
Carrier frequency: 98 MHz
Output
level:
1
mV
(60
dB)
B)
Simple
Method
Setting: FUNCTION Selector: TUNER
Modulation:
Procedure:
pe
(400
ie
20
kHz
deviation
(50
%)
Band
Selector:
FM
1
sn
thevaat
do
he
EMC
dare
proudeasting
Sasial
Pilot
(19
kHz):
6.3
kHz
deviation
(16
%)
MO
;
:
:
set
to
tne
stereo
br
a
.
Sub
channel
(38
kHz):
20
kHz
deviation
(50
%)
BE
Seeetok
STEREO
(EMD
AM
NITE
2.
Turn
RT302
clockwise
or
counterclockwise
and
Procedure:
A)
Regular
Method
memorize
the
lighting-up
range
of
STEREO
lamp.
FM
stereo
VTVM VTVM
ich
alee
3.
Secure
RT302
at
the
center
in
lighting-up
range
of
signal generator
output channel
LCH
connection
reading
generator
both
turns
as
shown
below.
Adjust RT301
RCH
LCH
resistor
for
minimum
reading.
center in lighting-up ranges
Carrier
frequency:
98
MHz
FM
ANTENNA
lighting-up
range
Output level: 7mV 752
Modulation: no modulation ft © '
\\ }/
R318 R317
c314()
frequency counter
©
Adjust RT301
R-CH resistor for
minimum
reading.
L-CH Stereo separation: @ -
R-CH Stereo separation: © - ®)
The difference between separations @)->®)
and ©-D are to be equal.
Procedure:
Adjust
RT302
for
76
kHz
+100
Hz
on
the
frequency
counter.
atte
Sy

Replacement Semiconductors
For replacement, use semiconductors except in (
1201: CX168
24 22 20.18 16 14
9}17 [15/13
7
(ZF4O678 910112
(Top view)
1C301: CX178
715 13 G4
18 {16 [14412] 10
123456789
{Top view)
IC601,651: HA1350S
12345676910
(Marking side view)
0301, 702, 703 : 2SC1364 |
Q501, 502 (2SC1815)
0551, 552!° 28¢1362 |
c
A
E
Fc.
Q701: 2SD809
letter side
!
|
! Cy,
|
!
Q704: 2SA1027R (2SA844)
i ©
Q705: 2SC1475 (2SD789)
j &
D201, 301, 302, 308, 309
D704, 706, 707, 709, 710
D703
| : 181555
: 10E2
cathode
: GLOPR21 (GLOPR)
i
- anode | cathode
D303
D304, 305,306 : GL2PR1 (GL2PR)
short
Jong
cathode anode
D307: EQB01-11Z (EQA01-11R)
D702: EQB01-16 (EQA01-16R)
D705: £QB01-26 (EQA01-26R)
cathode
aE)
i
D701: S3VC40R (S2VC20R)
brown
D708: S3VC40 (S2VC20)
black
t
23
i. er aS
opt
Lee ie
-~13-
STR-232L
Tesco
SS itl
ee gn) or
7k
n
EY S32 FS “oe TN |
ARs
AR
~ aafeebihe an
gr Q
|
I