Pioneer PD-M427 Servise Manual page 28

PD-M427, PD-M407
11. Focus Best Adjustment
Adjust this point only if adjustment was made in item 10.
Test mode
=
SPDL servo
=
FOCUS servo
=
TRKG servo
Innermost
TEST DISC
circumference
(1 TRK)
PLAY
START
(CN201)
FE
RF
VC
MOTHER BOARD ASSY
12. Tracking Servo Loop Gain Adjustment
Test mode
SPDL servo
FOCUS servo
TRKG servo
Innermost
TEST DISC
circumference
(1 TRK)
PLAY
START
TP1
(CN201)
2
TE
3
TI
4
VC
MOTHER BOARD ASSY
28
CLOSE
CLOSE
CLOSE
MOTHER BOARD ASSY
Player
TP1
6
1
4
=
CLOSE
=
CLOSE
=
CLOSE
MOTHER BOARD ASSY
Player
VR156
Adjust the RF level to maximum, with
the focus error voltage within ±150mV.
Prove (10:1)
Prove (10:1)
UNDER
VR151
Prove (10:1)
Prove (10:1)
100kΩ
MAX
Oscilloscope
DC Mode
CH1: 5mV/div
CH2: 20mV/div
H: 200ns/div
UPPER
JUST
Lissajous Waveform
Oscilloscope
X-Y Mode
X: 20mV/div
Y: 10mV/div
Low-frequency
oscillator
1.2kHz
1Vp-p
GND