Technics SL-PS740A - Checking of the Main P.C; Measurements and Adjustments

SL-PS740A ;
m@ CHECKING OF THE MAIN P.C.B.
1. Remove the cabinet (see Ref. No. 1 of the disassembly
instructions). Main P.C.B. Lead wire
2. Remove the front panel ass’y (see Ref. No. 2 of the
same).
3.
Remove
the
operation
P.C.B.
(see
Ref.
No.
4
of
the
Rear
panel
same).
ass'y
4. Remove the main P.C.B. (see Ref. No. 9 of the same).
5. Don't remove the 7 connectors (CN11, CN12, CN13,
CN401, CN415, CN431, CN871).
6. Connect the main P.C.B. ground terminal (LINE OUT
terminal) to the rear panel ass’y with a lead wire.
Ground terminal
(LINE OUT) —
When checking the soldered surface of the main P.C.B.
and replacing the parts, do as shown below.
Box or stand to make operation
P.C.B. stand.
Operation P.C.B.
m@ MEASUREMENTS AND ADJUSTMENTS
Caution:
1. It is very dangerous to look at or touch the laser beam. (Laser radiation is invisible.)
With the unit turned “on”, laser radiation is emitted from the pickup lens.
Avoid exposure to the laser beam, especially when performing adjustments.
2.
During
laser
power
or
focus
offset
adjustment,
never
connect
the
other
probe
to
the
unit.
(Otherwise the unit’s power supply will sustain damage.)
Oscilloscope
PREPARATION
1.
Remove
the
cabinet
(see
Ref
No.
1
of
the
disassembly
‘©
instructions).
. Remove the disc holder (see Ref No. 7 of the same).
. Place the test disc on the turntable.
. Turn “ON” the power switch at the player.
.
Push
the
bracket
of
tray
SW
($1001)
in
the
direction
of
the
Disc
lid
arrow
and
release
it.
Note:
If
the
test
disc
fails
to
rotate,
press
the
tray
switch
Test
disc
again. 3S =.
Tray SW (S1001)
MO & Wh
-~12-