Sharp PZ-50HV2U Service Manual page 25

Timing Adjustment of X and Y DRIVE Assys Control Signal
Purpose
• Pulse module loads in DRIVE Assy as one of heat measures of DRIVE Assy. Adjust the drive timing of the pulse module
driving parallel with VR.
• Pulse module has each peculiar delay time. Readjustment is necessary when replaced the pulse module in the X and
Y DRIVE Assys.
Adjustment Method
CR delay circuit is each inserted on signal path of four control signals (SUS-U, SUS-B, SUS-D, SUS-G) driving
the pulse module.
Quantity of delay can adjust pulse module of one side with VR.
Adjust VR while measuring a waveform of the pulse module, and match a timing.
Adjustment VR
X DRIVE Y DRIVE
SUS-U VR3203 VR2204
SUS-D VR3202 VR2203
SUS-B VR3201 VR2202
SUS-G VR3200 VR2201
Adjustment Procedure
Power ON
Black Mask Screen
Display a SUSOUT waveform
Coarse adjustment of
SUS-U, SUS-B, SUS-G
Display a SUS-D waveform
SUS-D adjustment
Adjust the waveform to 20-25ns.
Display a SUS-U waveform
SUS-U adjustment
Adjust the waveform to 20-25ns.
Power OFF
Adjust VR resistance value
of SUS-B and SUS-G to match
VR resistance value of SUS-D
within 2 .
As for this adjustment, adjustment with set state is difficult.
Therefore replace it every Assy when replacing the pulse module.
Test pin for adjustment and measurment
Pulse Module
SUSOUT
SUS-U
SUS-D
Measuring points of waveform
are refered to next page.
SUS-D readjustment
Adjust the waveform to 20-25ns.
SUS-U readjustment
Adjust the waveform to 20-25ns.
Adjust VR resistance value
of SUS-B and SUS-G to match
VR resistance value of SUS-D
within
Compare waveform,
and do harmonize
25
X DRIVE
Upper Lower
K3105 K3106
K3200 K3204
K3108 K3205
Power ON and
display a SUS-D waveform
Display a SUS-U waveform
Power OFF
2 .
Power ON and display a SUSOUT
waveform
No
almost?
Yes
Adjustment end
PZ-50HV2, PZ-50HV2E
PZ-50HV2U
Y DRIVE
Upper Lower
K2212 K2203
K2220 K2224
K2207 K2225