HITACHI 42PMA300EZ
Manual de Servicio

(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 190V) ¤º 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. ¤æ 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 adds 6V to Max value(Vsmin1~Vsmin5) and set up the voltage within the set-up range(180V < Vs # 190V) in consideration of other features. ¤ Turn the voltage adjusting knob of Vs DC power supply make deciding the Vs voltage. ¤ı Adjust Vset-down wave form using setting up Vs voltage like mentioned on the 4-3.

(4) Adjusting the final voltage wave form
Check the voltage wave form like the mentioned way on the 43(How to adjust) and readjust the wave form when it is twisted.

(5) DC-DC Pack Voltage Set up Range
Vsetup : 185V ~ 225V Vsc : 90V ~ 120V -Vy : -60V ~ -80V

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