Technics SL-PC25

Mi SCHEMATIC DIAGRAM
(Parts list on pages 42, 43, 49 and 50)
(This schematic diagram may be modified at any time with
development of new technology.)
OPTICAL PICKUP
(TRACKING)
( TRAVERSE ) ( FOCUS )
°$1
:
Power
switch
in
“on”
position.
A
RAL
POSITION
°S2
:
Voltage
selector switch.
(For
[GC,
PX]
areas.)
°SW41
:
SW block
(S410-S418).
°Sw42
:
SW
block
(S401-S409).
(OOP
°$401
:
Play
(play)
switch.
PY
servo
oe
BOS
ek
oh
Ae
°
$402
:
Pause
(pause)
switch.
C162.
ATR
era
¢
$403
:
Stop
(stop)
switch.
ara
|
2SA1547QSTV2
*$404,
405:
Skip
(skip)
switch.
em
aa
y
L
elas
AUTO
POWER
CONTROL
[S404:
F.
SKIP,
S405:
B.
SKIP]
Ch
i
Nee
St
a
Se
ad
|
°
$406
:
Program/continue
(program/continue)
switch.
1c103
4
*
*$407
~ 411:
Disc
(disc
1
~
5)
switches.
AN8377N
:
S407:
5,
S408:
4,
S409:
3,
/TRAVERSE
COIL
DRIVE
i
Eee
2,
S411:
1
|
(
BTL
DRIVE)
a
b
dad
¢
|
¢$412,
413
:
Search
(search)
switches.
~
CNIO3
|
+
mm
16V 100
(S412: F. SEARCH, $413: B. SEARCH] & Ka i
$414
:
Auto
link
(auto
link)
switch.
0,
$415 : Edit tape length (tape length) switch. 3 :
°S416
:
Time
mode
(time
mode)
switch.
oO
7
$417
:
Repeat
(repeat)
switch.
a
KS
|
$418
:
Random
(random)
switch.
b
re
:
$419 : Disc skip (disc skip) switch. - 3)
°$451
:
Clamp
switch.
Cc
os
—
ee
°
Koy
i
|
ro
Eywain
¢
The
voltage
value
and
waveforms
are
the
reference
voltage
of
53
{oave-s
2SB1240QRTV6
;
ie
)
CIRCUIT(CN3O1)
this unit measured by DC electronic voltmeter (high impedance) 2 en ae REGULATOR x ; Ret eerpne i Ke) ‘a
and oscilloscope on the basis of chassis. , y : = Ko) n
Accordingly, there may arise some error in voltage values and = 0.548 0.1V/01V 7 2 3 pexee :
waveforms depending upon the internal impedance of the tester Li | O.5V pp ot 4
or the measuring unit. [ 4 Ke) :
* The parenthesized are the values of voltage generated during H Ka s
playing (Test disc 1kHz, L+R, 0dB), others are voltage values : a : |
in stop mode. AEE ies J
¢ Important safety notice: soar Be eet
Components identified by A\ mark have special characteristics bee 1C102 aa bevSPiNDEE.
important for safety. When replacing any of these components, D “ RII 4.7K AN8374S AN8373S _ MOTOR
p o SERVO PROCESSOR we
use only manufacturer’s specified parts. g lel] ae SERVO AMP O (mp
° [ee--—-: : Positive voltage lines and negative och
ays] Svar RR Best eye ad
voltage lines. S)Et Ly wpenT, RK : ye adj. G)
: audio signal lines. ciae Cae i eer ea a ;
eva 3 Tracking
Caution! mes 2569) TPO 8 oe ahs
IC and LSI are sensitive to static electricity. Lyte 42 Rilo 120 += OSus O5WOIV
Secondary trouble can be prevented by taking care during repair. zak evar | vRi03 2Vp-p
¢ Cover the parts boxes made of plastics with aluminum foil. tov 994 snes MA & : w
¢
Ground
the
soldering
iron.
r
covagy
:
me
ceed
zs!
Bln
Cn
cee
2
Focus
offset
adj.
¢ Put a conductive mat on the work table. . ease - es Sivi ‘ og
© Do not touch the pins of IC or LSI with fingers directly. b— | G4) TR VF 3 spats aes ately oe ays
c
63v2
0.
ms.
d fevssor Waar [o av 2p
. (0149.6 cura B ijutetase toc ee
f C124 0082 BeAr Ploy
| (oviagy
f—t
G0)
cNTI
4
ce
-
Ak
476
eee
2ms.
O.1V/DIV
= = 0.15Vp-p
‘4.941
0
V8)
LON
‘
=
ze]
PM
eee
ee
ae
aa
Play
2ms.
0.1V/
DIV
m5 eer cg 0 Be | LL peo 92%0 na
L 4.2166) FLOCK vo —s ema C1)
9
ao
/
|
0.
C113.
Sov!
TEG
Tat
ef
/
‘
,
—
cia
0033
z
+)
Cus DOV! re
e® 7 10K) 13) To Servo Gain
C16 eS | is Adjuster
abe
ee
pee 1@))
ez { gain odj. | raeking
Pla Q a gain a
ito
gs
tes
Seve
t
me
--0V zs
O.5ps 2v/D1V. scene 2ps 2V/0IV ws 2V/ Div
—
29
—
—
30
—