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Note:
As a front-end (FE]1) is difficult to repair if faulty,
replace
it with
new
one.
TUNER
SECTION
FM SECTION
ADJUSTMENTS
Setting :
FM RF signal
generator
750 coaxial
Carrer
frequency:
98MHz
modulation : 1kKHz, 75kHz
deviation
FM
ANTENNA
terminal
(TB1
or TB2)
VOM
(DC range)
ee
FM Discriminator Alignment (NULL Check)
Band: FM
Procedure :
1.
Supply a lmV (60dBy) 98MHz signal from the ANTENNA
terminal.
2.
Tune the to 98MHz.
3.
Adjust IFT82 for 0V reading on the VOM.
Note: FM tuned indication lighting level adjustment should
be made after FM discriminator alignment.
Adjustment Location: main board
FM Tuned Indication Lighting Level Adjustment
Band:
FM
Procedure:
1.
Supply a 24 uV (25dBy ) 98MHz signal from the ANTEN-
NA
terminal.
2.
Tune
the set to 98MHz.
3. Adjust RV81 so that the
light up.
e
Repeat the procedures in each adjustment several times,
and
the frequency
coverage
and
tracking
adjustments
should
be finally done
by trimmer
capacitors.
AM SECTION ADJUSTMENTS
Setting:
loop antenna B
loop antenna A
AM RF signal
generator
;
y)
30% amplitude
modulation by 400Hz signal
MW Tuned Indication Lighting Level Adjustment
Band: MW
Procedure:
1.
Set loop antenna A so that the loop antenna, B input
level becomes 0.45mV (55dByu )
2.
Tune the set to 999kHz.
3.
Adjust the RV82 so that the
light up.
SW OSC Voltage Adjustment
Band: SW
Procedure :
Connect the VOM to TP (OSC).
Tune the set to 5.95MHz.
Adjust T2 for 0.9 to 1.1V reading on the VOM.
Tune the set to 17.90MHz.
Adjust CT22 for 8.3 to 8.7V reading on the VOM.
SY I OO)
SW Tracking Adjustment
Band: SW
Procedure:
1.
Cornect the VOM to speaker terminal.
2.
Adjust for a maximam reading on VOM.
Signal generator and
Adsustnene part
Set frequency
17.0MHz
CT21
a
eee
Adjustment Location:
main board —component side—
[MAIN BOARD] (COMPONENT SIDE)
TB2
ANTENNA
cT21
SW TRACKING
ADJ
cT22
Sw OSC
TI
SW TRACKING
ADJ
T2
Sw OSC
VOLTAGE ADJ
RV81
FM TUNED
INDICATION
LIGHTING
LEVEL ADJ
IFT 82
FM DISCRIMINATOR
ALIGNMENT
TP81
MW (AM) TUNED
INDICATION
LIGHTING
LEVEL ADJ
CD SECTION
Note:
1.
CD Block basically constructed to operate with-
out
adjustment.
Therefore,
check
each
item
in
order given.
2.
Use YEDS-18 disc (3-702-101-01) unless otherwise
indicated.
Use the oscilloscope
with more
than
10M!2 im-
pedance.
4.
Clean an object lens by an applicator with neutral
detergent
when
the
signal
level
is low
than
specified value with the following checks.
S Curve Check
oscilloscope
BD
board
ere,
TP (FEO)
om—-o¥
TP (VC)
ow—lo-
Procedure :
1.
Connect oscilloscope to test point TP (FEO) on
BD board.
2.
Connect between test point TP (FES) and TP
(VC) by lead wire.
3.
Turned
Power
switch on and actuate the focus
serch. (actuate the focus serch when disc table is
moving in and out.)
4.
Check
the oscilloscope
waveform
(S curve)
is
symmetrical between A and B. And confirm peak
to peak level within 341Vp-p.
S curve waveform
symmetry
within
3+1Vp-p
5.
After check, remove
the lead wire connected
in
step 2.
Note:
* Try to mesure
several
times to make
sure
that the ratio of
A: B or B:A is more than
10:7.
* Take sweep time as long as possible and light
up the brightness to obtain best waveform.
RF Level G
Procedure :
1.
Connect
BD boa
Turn Pq
Put disq
Confir
check R
Note:
Clear RF si
can be clea
form.
RF signal
E-F Balan
Procedure:
1.
Connec
(TEO)
2.
Connec
BD boa
Turn P
Put dis
5.
Confir
metrica
and ché
Traversé
alti
ov — -
aul
6.
Remove
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