Daewoo DP-42SM Service Manual page 51

3-5-3. How to Adjust
(1) Adjusting initial voltage wave form Check the voltage wave form like the mentioned way on
the 3-4-3(How to adjust) and readjust the wave form when it is wrong.
(2) Checking the DC/DC pack voltage
- Convert the signal of signal generator to the 100% Full White signal
- Connect the GND terminal of DVM to the GND of Y B/D and set the Plus terminal to the
right up leg of R9 to check the -Ve voltage (-35 1V). And when there is abnormality in
voltage turn the variable resistor (VR7) of DC/DC Pack(-Ve) on Y B/D to adjust.
- Connect the GND terminal of DVM to the R60 s right leg of the Y B/D and set the Plus
terminal to the left leg of R60 to check the Vscw voltage(115 1V) and when there is
abnormality in voltage turn the variable resistor(VR5) of DC/DC Pack(Vscw) on Y B/D to
adjust.
- Connect the GND terminal of DVM to the R8 s right leg of the Y B/D and set the Plus
terminal to the left leg of R8 to check the -Vy voltage(-80
abnormality in voltage turn the variable resistor(VR6) of DC/DC Pack(-Vy) on Y B/D to
adjust.
- Connect the GND terminal of DVM to the R89 s right leg of the Y B/D and set the Plus
terminal to the left leg of R89 to check the Vsetup voltage(240 1V) and when there is
abnormality in voltage turn the variable resistor(VR4) of DC/DC Pack(Vsetup) on Y B/D to
adjust.
(3) Measuring the Vs voltage Margin and deciding the voltage
- Convert the signal of signal generator to the 100% Full Red signal.
- Turn the voltage adjusting knob of Vs DC power supply to the voltage -down direction and
make the cell of screen turned off.
- Turn the voltage adjusting knob of Vs DC power supply to the voltage -up direction until
the cell of screen turned on. The first voltage, which make the cell of full screen turned on,
is named as Vsmin1 and record it.
- Turn the voltage adjusting knob of Vs DC power supply to the voltage-up direction slowly
until the cell of screen turned off or over electric discharge. The first voltage, which makes
the cell of screen turned off or over electric discharge, is named as Vsmax1 and records it.
(Only, Vs voltage variable passes over the maximum 195V)
- Convert the signal of signal generator to the 100% Full Green signal.
- Repeat the adjustment (2) item and name each voltage as Vsmin2/Vsmax2 and record them.
- Convert the signal of signal generator to 100% Full Blue signal.
- Repeat the adjustment (2) item and name each voltage as Vsmin3/Vsmax3 and record them.
- Convert the signal of signal generator to 100% Full White signal.
- Repeat the adjustment (2) item and name each voltage as Vsmin4/Vsmax4 and record them.
- Convert the signal of signal generator to 100% Full Black signal.
- Repeat the adjustment (2) item and name each voltage as Vsmin5/Vsmax5 and record them.
- At this time decided Vs voltage (Vsmin1-Vsmin5) adds 6V to Max value and set up the
voltage within the set-up range(180V < Vs
- Turn the voltage adjusting knob of Vs DC power supply make deciding the Vs voltage.
- Adjust Vset down wave form using setting up Vs voltage like mentioned on the 3-4-3.
(4) Adjusting the final voltage wave form Check the voltage wave form like the mentioned way
on the 3-4-3(How to adjust) and readjust the wave form when it is twisted.
195V) in consideration of other features.
-50-
Adjustment
1V) and when there is