Technics SL-P250 - Page 8

Mi MEASUREMENTS AND ADJUSTMENTS
SL-P250 SB 2510)
Caution:
@
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.
PLAYER SETTING
1. Remove the cabinet. (Refer to page 9.)
2. Remove the disc clamper and magnet. (Refer to
page 9.)
3. Remove the disc holder and power switch rod.
(Refer to page 9.)
© Setting of the test disc (Shown at the right figure.)
1. Place the test disc and magnet.
2. Turn “ON” the power switch of the player, while
holding the levers of the switches ($101, S102)
in the direction of the arrow.
3. Release the levers of the switches (S101, $102)
after the test disc starts rotating.
ADJUSTMENT POINTS
¢ Servo P.C.B.
(Focus
offset adj.)
[pte
VR106 VR501| (PLL adj.)
(Tracking VR102] (Tracking gain adj.)
balance adj.) [vR101] (Best eye adj.)
(Tracking offset adj.)
© Main P.C.B.
LINE OUT
(L) (R)
| PLL adjustment test point
Dis (+12V)
->-” Connect the red lead
i j :
D21 wire of servo gain ajuster
@ (—12V)
Connect the blue lead
wire of servo gain adjuster.
¢ Filter for turntable height adjustment
Resistor: 10kQ
(ERDS2TJ103)
To oscilloscope (+)
Capacitor: 0.1pF
(ECQM1H104KV)
To oscilloscope (—)
ELECTRICAL ADJUSTMENT
Measuring Instruments and Special Tools
@ Servo gain adjuster (SZZP1017F)
@Test discs
Test disc (SZZP1014F) old or new type
Inspection test disc (SZZP1054C)
Uneven disc (SZZP1056C)
Black band disc (SZZP1057C)
@ Ordinary disc
@ Two-channel oscilloscope (with trigger)
of 30MHz or over
@ Low frequency oscillator
@ Conversion connector(SZZP1032F)
Step 7:Tracking offset adjustment.
(Refer to page 16.)
Step 8:Tracking offset balance
adjustment. (Refer to page 16.)
Step 9:Disconnect the servo gain
adjuster.
Step 10:PLL adjustment.
(Refer to page 17.)
Step 11: Check of play operation after
adjustment. (Refer to page 17.)
Adjustment Procedure
Step 1:Make the temporary setting of
each VR . (Refer to page 15.)
Step 2:Best eye ( PD balance ) adjustment.
(Refer to page 15.)
Step 3:Connect the servo gain adjuster.
(Refer to page 14.)
Step 4:Focus gain adjustment.
(Refer to page 15.)
Step 5:Tracking gain adjustment.
(Refer to page 15.)
Step 6:Focus offset adjustment
(Refer to page 16.)
Connection of Servo Gain Adjuster
Low-frequency oscillator
©OO0O
Servo gain adjuster |
(SZZP1017F) GND OSC Oscillator connection terminals
ON/OFF switch
pari ee 2 Conversion connector
GNO® « (SZZP1032F)
Selector }
oO F osc @®
7 2 fF)
Tp3Tp2 ° i
@@®@ TP!
or
»|
=
i
iy
|
Oscilloscope Oscilloscope connection 1
Red
Wr)o_o terminals
~~} ©
OO] TP2 TP3 TPr
CHIp _9CH2
me f ! | ‘
-—12V GND +12V
(Main) (Chassis) (Main)