Sharp SC-103H User manual

== Service
MODELS
SC-103H
CP-108H
CONTENTS
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ELECTRICAL SPECIFICATIONS
Circuit: .
Semiconductors:
Power Source:
Power Consumption:
Speakers:
Dimensions: (S§C103H)
(CP-108H)
Weight:
FM SECTION
Frequency Coverage:
Maximum Sensitivity:
IF Rejection:
Image Rejection:
Frequency Response:
Harmonic Distortion:
Signal to Noise Ratio:
FM STEREO SECTION
Stereo Separation:
Stereo Indicator Lighting Level:
Harmonic Distortion:
Signal to Noise Ratio:
AM SECTION
Frequency Coverage:
Maximum Sensitivity:
IF Rejection:
Image Rejection:
AGC Figure of Merit:
Band Width:
Harmonic Distortion:
FM/AM 2:-band superheterodyne
system stereo tuner-amplifier with
FM multiplex circuit with AFC and
4 track cassette tape recorder and
2 way speaker system
31-transister. J-FET. 1-IC.
110/220/240V, 50Hz
60 watts
Woofer 6-1/2" x 2
Tweeter 1-5/8" x 2
20-3/4"(W)x10-1/2"(D)x5-1/4"(H)
9-3/4"(W)x5-1/2"(D)x13-11/16"(H)
(SC103H) = 15.2Ibs
(CP-108H) 4.2Ibs x 2
15-diode
88 — 106MHz
1.6uV
70 dB
48 dB
70 — 10kHz
1%
45 dB
35 dB
10uV
1%
45 dB
520 ~- 1,620kHz
130nV/m
30 dB
40 dB
$0 dB
5.5kHz
2%
AUDIO SECTION
Total Peak Music-Power
Output:
Distortion at 500mW:
Frequency Response:
Hum and Noise Level:
Sensitivity for Rated Output:
Channel Separation:
Tone Characteristics:
20W
0.5%
40Hz ~ 22kHz
Residual Volume 3mV
Maximum Volume Phono MM 60mV
Tape 60mV
Phono M.M. ImV
50 dB
Bass Boost at 100Hz +8 dB
Cut at 100Hz -11dB
Treble Boost at 10kHz +8dB
Cut at 10kHz ~15 dB
TAPE RECORDER SECTION
Type:
Tape:
Tape Speed:
Record/Playback Time:
Recording System:
Erasing System:
Wow & Flutter:
Fast Forward & Rewind Time:
Frequency Response:
Distortion:
Signal to Noise Ratio:
Channel Separation:
Erase Ratio:
Input Circuitry:
Sensitivity & Input Impedance:
MIC
Line
4-track 2-channel stereo cassette
tape recorder
Philips type compact cassette tape
1-7/8 ips
60 minutes (C-60)
AC bias 53.5kHz
AC erasing
0.45% weighted peak
70 seconds (C-60)
40Hz to 12,000Hz
1.6%
46 dB
35 dB
65 dB
MIC x 2(microphone impedance 5002)
DIN-TYPE
0.1mV, @47KQ impedance
50mV, @220KQ impedance
Figure 1
DISASSEMBLY
2

DISASSEMBLY
CHASSIS REMOVAL (Refer to Figure 1)
1. Disconnect all leads connected to the back of the set.
2. Remove 7 screws (1) retaining the chassis (2).
3. Gently pull forward the panel (3) and chassis from the
cabinet (4).
FRONT PANEL REMOVAL
_ 1. Remove the cabinet as described in Chassis Removal.
2. Remove 8 knobs (5,6,7,8) from front of the panel.
3, Remove 9 screws (9) retaining the front panel.
4. Gently pull out the panel while holding both sides.
Figure 2 DIAL CORD STRINGING
OPERATING MODES
1. STOP Mode
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1.
MECHANISM ADJUSTMENT
AUTOMATIC SHUT-OFF MOTION ADJUSTMENT (Refer to Fig. 17 and Fig. 18)
Sic
ADJUSTING
SCREW--(A)
or
veal)
[Sy
18+02m
(5/64" +1/64")
=)
Figure 17
Adjust
the
position
of
the
electromagnet
by
using
a
thickness
gauge
so
that
a
distance
becomes
approximately
1.8+0.2mm(5/64"41/64")in
STOP
mode,
as
shown in
Fig.
17.
Adjust
the
nut
so
that
clearance
between
STOP
lever
(081)
and
(082)
becomes
0.1
to
0.3mm
(1/128"~1/64").
FLYWHEEL THRUST CLEARANCE ADJUSTMENT (Refer to Fig. 19)
THRUST ADJUSTING SCREW
0.1~O.3mm
(I/128°~1/64")
Figure 19

3. MOTOR SWITCH POSITION ADJUSTMENT (Refer to Fig. 20)
it
SW3
~ADJUSTMENT POINT
Figure 20
4. PRESSURE ROLLER ADJUSTMENT (Refer to Fig. 21)
READING
STOPPER CAPSTAN SHAFT 275t 259r
PRESSURE
(9.7+0.880z)
GAUGE
Figure 21
1) Adjust the pressing force of the pressure roller (101) to the capstan shaft in PLAY mode.
2) Read the value of pressing force when the pressure roller (101) moves off the capstan shaft.
3) At the time, in PLAY mode check that clearance between the pressure roller (101) and the stopper is around
0.5mm (1/32”).
5. TURNTABLE DRIVING PULLEY PRESSURE ADJUSTMENT (Refer to Fig. 22)
ADJUSTMENT HOLE
PLAY Mode , 096
(1.7 740.35 0z)
TENSION GAUGE (O~I100g)
(0 ~350z)
Figure 22
1) Measure the pressing force, hooking a tension gauge on the slip roller lever (083).
2) Read the pressing force when the take-up turntable (108) stops.
8

6.
FAST
FWD
ROLLER
PRESSURE
ADJUSTMENT
(Refer
to
Fig.
23)
READING
[ste |
(6.35 +1060z)
TENSION GAUGE toes
O-~100z
068
Figure 23
1)
Hook
a
tension
gauge
on
A
part
of
FAST
FWD
roller
(085)
in
FAST
FWD
mode
and
read
the
tension
gauge
when
the
take-up
turntable
(108)
stops.
Adjustment
is
made
by
bending
the
spring
(161).
7.
REWIND
ROLLER
PRESSURE
ADJUSTMENT
(Refer
to
Fig.
24)
TENSION GAUGE (0~100g)
(0 ~350z)
Figure 24
1)
Set
a
tension
gauge
at
A
part
of
the
REWIND
roller
lever
(086)
in
REWIND
mode
and
read
the
tension
gauge
when
the
supply
turntable
(101)
stops..
Adjust
the
tension
by
the
spring
(159).
8. BRAKE LEVER ADJUSTMENT (Refer to Fig. 25)
088 ADJUSTMENT SCREW
108 107
Figure 25
1)
Check
that
the
brake
lever
(088)
is
pressed
against
the
turntables
(107
&
108)
in
STOP
mode
and
that
the
brale
lever
(088)
is
apart
at
the
same
distance
from
the
turntables
(107
&
108)
in
PLAY,
FAST
FWD
and
REWIND
moks.
Adjust it by the retaining screw.

9. SUB-CHASSIS STROKE ADJUSTMENT (Refer to Fig. 26)
155
ADJUSTMENT SCREW
CASSETTE
HOLD
PIN
Figure 26
1) Adjust the sub-chassis adjusting bracket (155) so that the long hole of the sub-chassis (058) is pressed against the
cassette hold pin in PLAY mode and also in STOP mode.
10. PAUSE MECHANISM ADJUSTMENT (Refer to Fig. 27 and Fig. 28)
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10)
.omm( 1/32")
Figure 27 Figure 28
1) Depress the PAUSE button in PLAY mode and check that clearance between the pressure roller (101) and the
capstan shaft is over 0.5mm (1/32”). Adjust it by bending A part of the pause operating lever (072).
2) After adjustment, depress only the PAUSE button and, in PLAY mode, check that clearance between the pressure
roller lever (101) and B part of the pause operating lever (072) is over 1mm (3/64").
3) Adjust it by bending C part so that the take-up turntable (128) and the pressure roller (101) simultaneously
stop when PAUSE button is depressed in PLAY mode.
4) Disengage PAUSE button and check that clearance at C part is over Imm (3/64”) in PLAY mode.

11.
TRANSPORT
POWER
SWITCH
(SW-5
SW-6)
ADJUSTMENT
(Refer
to
Fig.
29)
1)
For
SW-5,
check
that
A
and
Bare
in
contact
with
each
other
but
C_
is
apart
in
STOP
mode
and
that
A
and
C
are
in
contact
but
Bis
apart
in
PLAY,
FAST
FWD,
REWIND
modes.
2)
For
SW-6,
check
that
D
and
E
are
in
contact
with
each
other
in
PAUSE
mode
and
apart
when
PAUSE
button
is
disengaged.
3) Adjust it by the retaining screw.
SW6 O72 SW5 O74
Figure 29
12, TORQUE CHECK (Refer to Fig. 30)
DIAL TORQUE. GAUGE
TORQUE (0~150g-cm)
PLAY mode 45+15g.cm (6.4742.150z-inch )
FAST FWD mode 80+£20g-cm (11.5+2.87 02-inch ) ae
REWIND mode 100420g.cm (14.4+2.87 0z-inch ) LJ
Stop the motion of the revolving turntable by tightening
Dial Torque Gauge, and then loosen the Gauge gradually
in the direction of turntable revolution.
Read the gauge value when the turntable has begun
rotating.
(
108 107
Figure 30
13. BACK TENSION TORQUE CHECK (Refer to Fig. 31)
TORQUE
PLAY mode less than 18-cm (0.14 oz.inch )
REWIND mode less than 6g.cm (0.71 oz-inch )
MEASURING REEL
TENSION
GAUGE
(O~I0g)
(0~0,350z)
TURNTABLE (iO7 & 108)
Figure 31
11

14. CASSETTE HOLDER FALL TIME ADJUSTMENT (Refer to Fig. 32)
1) Check that the cassette tape exact-
ly falls into the cassette holder
(112) when inserted.
For adjustment, refer to the figure.
\
075
ADJUSTING SCREW
Figure 32
ELECTRICAL MEASUREMENT
SPECIAL EQUIPMENT REQUIRED
The following items will be required for performing electrical checks and adjustments:
1. DC constant-voltage power source (DC 20.0V)
DC voltmeter (DC 20V)
V.T.V.M.
Frequency counter
Signal generator
Attenuator
Distortion meter
Test tape (MTT-113, 6.3kHz recorded)
Oscilloscope
8 ohm dummy resistor (5%, 10W)
Test tape (MTT-112, 333Hz recorded)
Test tape (MTT-117A 63Hz, 1kHz, 8kHz recorded)
Blank tape
AC ammeter
Band Pass Filter (1 kHz)
CPN ANAwWD
eRe PP Pe
WRoONES
—_
POWER AMPLIFIER CHECK (Refer to Fig. 33)
1) Set Mode Selector Switch (SW-8) at “CASSETTE PLAY”.
2) Set VOLUME Control (R207, R208), RECORD MONITOR VOLUME Control (R213, R214) in the minimum
position, and BASS Control (R209, R210) and TREBLE Control (R211, R212) in the central position.
3) Connect DC constant voltage power source (DC 20.0V) to the power lead wire of main amplifier.
4) Connect PLUS side of DC voltmeter to TP101 (TP102) and MINUS side to TP2. Adjust R307 (R308) so that the
voltmeter’s reading becomes 10.0V.
5) -Connect PLUS side of DC voltmeter-to TP103 (TP104) and MINUS side to TP105 (TP106). Adjust R317 (R318)
so that voltmeter’s reading becomes 20mV.
12

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33
2. RECORD AMPLIFIER BIAS OSCILLATOR CHECK (Refer to Fig. 34)
RECORD
mode
Oscilloscope
R/P HEAD
Frequency Counter
Figure 34
Set Mode Selector Switch (SW-8) at “CASSETTE PLAY”.
Set the unit at RECORD mode.
Shift R.LF. Switch (SW-4) to “A”.
Connect V.T.V.M. to Test Point (R5, R6).
Adjust Semi-variable resistor (R409, R410) so that VTVM’s reading becomes 50mV.
Adjust Oscillator Coil (L401) so that the frequency counter’s reading becomes 53.5kHz+1.5kHz.
After checking bias frequency, re-check for the item 5.
Then shift R.I.F. switch (SW-4) to “B” and check that bias frequency becomes 52.25kHz+10%.
13

3.
ERASE
VOLTAGE
CHECK
(Refer
to
Fig.
35)
Oscilloscope
RECORD
mode
V.T.V.M
ERASE HEAD
Figure 35
1) Set Mode Selector Switch (SW-8) at “CASSETTE PLAY”.
2) Then set the unit at RECORD mode.
3) Set R.ILF. Switch (SW-4) at “A”.
4) Connect VTVM to Resistor (R408).
5) It is normal if VTVM’s reading is then over 55mV.
4. LEVEL METER SENSITIVITY CHECK (Refer to Fig. 36)
Oscilloscope
CR.
OSC
V.T.V.M
RECORD mode R/P HEAD
Attenuater
—-l0dB
100 ohm
Figure 36
1) Set Mode Selector Switch (SW-8) at “CASSETTE PLAY”.
2)
Set
RECORD
MONITOR
VOLUME
Control
(R213,
R214)
in
the
maximum
positions,
and
BASS
Control
(R209
R210)
and
TREBLE
Control
(R211,
R212)
in the
central
positions.
3)
Remove
the
ground
lead
of
bias
circuit
at
main
amplifier
and
stop
bias
oscillation.
4) Set the unit at RECORD mode.
5)
Input
-10dB,
1kHz
signal
to
LINE
IN
Jack
(SO701,
SO702)
and
adjust
VOLUME
Control
(R207,
R208)
so
that
voltage
‘at
both
ends
of
resistor
(R5,
R6)
becomes
3.5mV.
6) Adjust Semi-variable resistor (R119, R120) so that LEVEL meter indicates OVU.
’
5. RECORD AMPLIFIER SENSITIVITY CHECK (Refer to Fig. 37)
cCR.OSC
KHz RECORD mode
Attenuater
MIC or
LINE iN
Figure 37
14

Set
RECORD
MONITOR
VOLUME
Control
(R213,
R214)
in
the
maximum
position,
and
BASS
Control
(R209,
R210)
and
TREBLE
Control
(R211,
R212)
in
the
central
positions.
Set
VOLUME
Control
(R207,
R208)
in
the
maximum
position.
Set the unit at RECORD mode.
Remove
the
ground
lead
of
bias
circuit
at
the
main
amplifier
and
stop
bias
oscillation.
Input
1kHz
signal
to
MICROPHONE
Jack
(J701,
J702).
Microphone
sensitivity
is
normal
if
attenuator’s
reading
is
within
the
range
of
-76
dB
to
~84
dB
when
LEVEL
meter
indicates
OVU.
Do
the
same
for
LINE
IN
Jack
(SO701)
as
did
for
microphone.
LINE
IN
sensitivity
is
normal
if
attenuator’s
reading
is
within
-22
dB
to
-30
dB.
Do
the
same
also
for
PHONO
Jack
(SO702)
as
did
for
microphone.
PHONO
sensitivity
is
normal
if
attenuator’s
reading
is
within
-56
dB
to
-64
dB.
NOTES:
1)
The
check
must
be
done
after
the
LEVEL
METER
Sensitivity
Check.
2) Channel to channel sensitivity must be within 4 dB.
6.
RECORD
AMPLIFIER
FREQUENCY
CHARACTERISTIC
CHECK
(Refer
to
Fig.
38)
Oscilloscope
RECORD mode R/P HEAD
Attenuater LINE IN
Jack
100 ohm
Figure 38
Set
Mode
Selector
Switch
(SW-8)
at
the
position
of
“CASSETTE
PLAY”.
Set
RECORD
MONITOR
VOLUME
Control
(R213,
R214)
in
the
maximum
position,
and
BASS
Control
(R209,
R210)
and
TREBLE
Control
(R211,
R212)
in
the
central
position.
Set the unit at RECORD mode.
(Remove
the
ground
lead
of
bias
circuit
at
the
main
amplifier
and
stop
bias
oscillation.)
Input
-10
dB,
1kHz
signal
to
LINE
IN
Jack
(SO701)
and
adjust
VOLUME
Control
(R207,
R208)
so
that
voltage
at
both
ends
of
resistor
(R5,
R6)
becomes
ImV.
Then
change
the
oscillator
frequency
to
63Hz
and
8kHz
and
if
deviations
to
1mV
are
within
-1
dB
to
+3
dB
ad
+10
dB
to
+14
dB,
respectively,
the
RECORD
AMPLIFIER
frequency
characteristic
is
normal.
15

7. PLAYBACK AMPLIFIER SENSITIVITY CHECK (Refer to Fig. 39)
Oscilloscope
Attenuater
R/P HEAD PLAY BACK mode
Speaker
Jack
Oummy
Figure 39
Set Mode Selector Switch (SW-8) at “CASSETTE PLAY”.
Set VOLUME Control (R207, R208) in the maximum position, BASS Control (R209, R210) and TREBLE Control
(R211, R212) in the central position.
Set the unit at PLAYBACK mode.
Disconnect the ground lead wires (red) of Record/Playback head for both channels. Input 1kHz signal between
head terminal and lead wire.
Connect 8 ohm (£5%, 10W) dummy resistor to Speaker Jack (SO704, SO705)
PLAYBACK AMPLIFIER sensitivity is normal if attenuator’s reading is -78 dB to -84 dB when voltage at both
ends of resistor becomes 3.3V.
8. PLAYBACK AMPLIFIER FREQUENCY CHARACTERISTIC CHECK (Refer to Fig. 39)
fBwWwWNnN
)
)
)
)
5)
6)
Set Mode Selector Switch (SW-8) at “CASSETTE PLAY”.
Set BASS Control (R209, R210) and TREBLE Control (R211, R212) in the central position.
Set the unit at PLAYBACK mode.
Disconnect the ground lead wire (red) of Record/Playback head for both channels.
Input 1kHz, -81 dB signal between head terminal and lead wire.
Connect 8 ohm (45%, 10W) dummy resistor to speaker jack (SO704, SO705) and adjust VOLUME Control (R207,
R208) so that voltage at both ends of resistor becomes 0.2V.
Then change the frequency of signal generator to 63Hz and 8kHz, and if deviations to 0.2V are +13.5 dB to
+19.5 dB and +1 dB to -5 dB, respectively, the PLAYBACK AMPLIFIER frequency characteristic is normal.
16

9. TONE CHARACTERISTIC CHECK (Refer to Fig. 40)
Oscilloscope
V.T.V.M
CASSETTE PLAY mode
Speaker
Attenuoter Jack
LINE IN
Figure 40
1) Set Mode Selector Switch (SW-8) at “LINE IN”.
2) Set BASS Control (R209, R210) and TREBLE Control (R211, R212) in the central positions.
3) Set the unit at RECORD mode, and RECORD MONITOR VOLUME Control (R213, R214) in the maximum
position.
4) Input -10 dB, 1kHz signal to LINE IN jack (SO701) and connect 8 ohm (45%, 10W) dummy resistor to
Speaker Jack (SO704, SO705) and adjust VOLUME Control (R207, R208) so that voltage at both ends becomes
0.2V.
5) Set the signal of signal generator at 125Hz and then output voltage is 0 dB.
6) At the time it is normal if the output deviation is within +5.5 to +9.5 dB when BASS Control (R209, R210) is set
at BOOST and within -7.5 to -11.5 dB when it is set at CUT.
7) Set the signal of signal generator at 8kHz and then output voltage is 0 dB.
8) It is normal if the output deviation is within +5 to +9 dB when TREBLE Control (R211, R212) is set at BOOST
and within -10.5 to -14.5 dB when it is set at CUT.
10. RECORD/PLAYBACK HEAD ADJUSTMENT (Refer to Fig. 41)
1) Set Mode Selector Switch (SW-8) at ‘““CASSETTE PLAY”.
2) Set BASS Control (R209, R210) and TREBLE Control (R211, R212) in the central positions.
3) Connect 8 ohm (45%, 10W) dummy resistor to Speaker Jack (SO704, $O705) and VTVM to its ends.
7

Insert ‘the test tape (MTT-113, 6.3kHz Recorded) into the unit.
Set the unit at PLAYBACK mode and adjust Head Azimuth Adjustment Screw (A) so that VIVM’s reading
becomes maximum for both channel 1 and channel 2.
NOTE: Be sure to apply a lock paint to screw (A) after adjustment.
Oscilloscope
V.T.V.M
PLAY BACK mode
R/P HEAD
Test Tape
Figure 41
11. PLAYBACK SENSITIVITY VOLTAGE CHECK (Refer to Fig. 41)
12. PL
1
ON
)
)
)
)
-
5)
Set Mode Selector Switch (SW-8) at “CASSETTE PLAY”.
Set VOLUME Control (R207, R208) in the maximum position, and BASS Control (R209, R210) and TREBLE
Control (R211, R212) in the central position.
Insert the Test tape (MTT-112, 333Hz Recorded) into the unit and set it at PLAYBACK mode.
Connect 8 ohm (45%, 10W) dummy resistor to Speaker Jack (SO704, SO705).
It is normal if voltage at both ends is within the range 1.3V ~ 2.5V.
Output voltage deviation should be below 4 dB for both channel 1 (left) and channel 2 (right).
NOTE: The check must be done after RECORD/PLAYBACK HEAD ADJUSTMENT.
AYBACK FREQUENCY CHARACTERISTIC CHECK (Refer to Fig. 41)
Set Mode Selector Switch (SW-8) at “CASSETTE PLAY”.
Set BASS Control (R209, R210) and TREBLE Control (R211, R212) in the central position.
Insert the Test tape (MTT-117A, 63Hz, 1kHz, 8kHz, Recorded) into the unit and set it at PLAYBACK mode.
Connect 8 ohm (45%, 10W) dummy resistor to Speaker Jack (SO704, SO705)and adjust VOLUME Control (R207,
R208) so that voltage at both ends becomes 0.5V at 1kHz and 0.5V is to be O dB.
Then playback 63Hz and 8kHz, and check output deviation to 1kHz. PLAYBACK frequency characteristic is
normal if deviation is -3 dB to +7 dB at 63Hz and -5 dB to +5 dB at 8kHz.
NOTE: Demagnetize Record/Playback head and guide before checking.
18

13. GENERAL FREQUENCY CHARACTERISTIC CHECK (Refer to Fig. 42)
Oscilloscope
Attenuater
V.T.V.M
CR. OSC —20dB RECORD mode PLAY BACK mode
Speaker
iv
Jack
LINE IN Jack
Tape Dummy
Figure 42
1) Set Mode Selector Switch (SW-8) at “CASSETTE PLAY”.
2)
Set
BASS
Control
(R209,
R210)
and
TREBLE
Control
(R211,
R212)
in
the
central
position.
3) Set RLF. Switch (SW-4) at “A”.
4) Insert the cassette tape (not recorded) into the unit and set it at RECORD mode.
5)
Connect
8
ohm
(+5%,
10W)
dummy
resistor
to
Speaker
jack
(SO704,
SO705)
and
VTVM
to
the
ends.
6)
Input
-10
dB,
1kHz
signal
to
LINE
IN
Jack
(SO701).
Adjust
VOLUME
Control
(R207,
R208)
so
that
LEVEL
meter
indicates
OVU.
Henceforth,
make
the
input
level
-20
dB
and
record
1kHz,
63
Hz,
8kHz
signals.
14, DIN INPUT/OUTPUT SENSITIVITY CHECK (Refer to Fig.43)
CR.OSC V.T.V.M
(kHz RECORD mode DIN Sock
Attenuater
(Out
sri
~ 26 dB
(A)
CR.OSC V.T.V.M
Attenuater
—20dB
(B)
DIN Socket SPEAKER
(Input) Socket aon
Figure 43
(A) 1) Set Mode Selector Switch (SW—8) at “CASSETTE PLAY”.
2) Insert the cassette tape into the unit and set it at RECORD mode.
3) Input -26dB, 1kHz signal to LINE IN Jack (SO701).
4) Connect 50K ohm dummy resistor to DIN Socket (Output terminal).
It is normal if voltage at both ends is within the range -34 dB.
(B) 1) Pull out Record Monitor control knob.
2) Input 1kHz signal to DIN Socket (Input terminal).
3) Connect 8 ohm (45%, 10W) dummy resistor to Speaker jack (SO704, SO705). and VTVM to the ends.
4) Adjust, Input Signal Level so that V.T.V.M. reading 3,3V. Henceforth, make the input level -20dB.
19

15. CHANNEL TO CHANNEL CROSSTALK (Refer to Fig. 43)
Band poss Oscilloscope
cR.osc Attenuoter
KHz -10dB RECORD mode PLAY BACK mode
LINE IN Tape
Figure 44
1) Set Mode Selector Switch (SW-8) at “CASSETTE PLAY”.
2) Set BASS Control (R209, R210) and TREBLE Control (R211, R212) in the central positions.
3) Set R.I.F. Switch (SW-W) at “A”. ‘
4) Insert a blank cassette into the unit and input -10 dB, 1kHz signal to LINE IN jack and record only in one channel
in the maximum position of VOLUME control (R207, R208).
5) Playback the tape after recording and connect 8 ohm dummy to Speaker jack (SO704, SO705) and adjust
VOLUME Control so that voltage at both ends of dummy becomes 3.3V.
Henceforth, output voltage through 1kHz Band Pass Filter is to be 0 dB.
6) Adjust VOLUME Control of the blank channel to the position of VOLUME Control of the recorded channel
mechanically.
7) Measure voltage at both ends of 8 ohm dummy through 1kHz Band Pass Filters. It is normal if deviation to
to output voltage compared with the above 5 is over 25 dB.
16. MEASUREMENT OF CURRENT CONSUMED (Refer to Fig. 44)
CR. OSC RECORD mode
Attenuater
Speaker
Jack
8 ohm Dummy
AC. Ammeter
110/220/240V
50Hz
Figure 45
20