Casio QV-8000SX, Service Manual & Parts List

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5-7. RGB AMP and Sub-Brightness voltage setting adjustment
1. Preparation
• AC adaptor or voltage regulator
• Digital oscilloscope
2. Adjustment procedure
(1) Start up Test mode Menu1.
1. Turn POWER on while pressing DISP key and MENU button simultaneously
2. Quickly press keys in the order of FLASH key, FLASH key and MENU key.
(2) Select / Execute GRAY SCALE (10 step).
(3) Impress the killer terminal (CP308) with VCC2-1 (CP344) voltage through a 22 k
Ω
resistance.
(4) Trigger VB waveform (CP322) by FRP (CP305) signal to adjust as noted below.
(5) Adjust RGB-AMP VR (VR302) so that pedestal-pedestal voltage of VG(CP322) signal is 3.50
±
0.05
Vp-p.
(6) Adjust SUB R BRIGHT VR (VR306) so that potential between VR (CP320) signal’s pedestal and pedestal
is 3.50
±
0.05 Vp-p.
(7) Adjust SUB B BRIGHT VR (VR305) so that potential between VR (CP324) signal’s pedestal and pedestal
is 3.50
±
0.05 Vp-p.
(8) Consecutively, execute 5-8. Contrast and Brightness voltage setting adjustment.
3. Notes
When unable to adjust using AC adaptor, use voltage regulator and supply power to be VCC-1-1 (CP105) =
5.0
±
0.05 V.
4. Connection diagram
3.5V
±
0.05V
(pedestal – pedestal)
Figure 1
L-PCB
VCC1-1
(CP105)
VR terminal(CP320)
VB terminal(CP324)
VG terminal(CP322)
(Figure 1)
Digital oscilloscope
Killer terminal (CP308)
VCC2-1(CP344)
QV-8000SX
Power supply