vertical problem

[thefixer]

hello every body ,I have Siera tv model sa2110 it has analog processor and analog processor tda9381ps/n3/2/1831.vertical chip is la78040.i checked its voltage supply it is about 16v .i substitute that chip but in vain .I think that there is no vertical signal .any one tohelp me with this .thanks in advance.

[minnie]

Have you replaced the pump up cap? Replace all the caps around the vertical IC. Depending on the age, the B+ should come off the flyback, go threw a protect resister then diode. You probably fried the IC again.

[thefixer]

[quote="minnie"]Have you replaced the pump up cap? Replace all the caps around the vertical IC. Depending on the age, the B+ should come off the flyback, go threw a protect resister then diode. You probably fried the IC again.[Yes i verified all cap around it .all components are ok.Finally i find that 7808 regulator doesn't work well .it was the cause.Thanks again for your advice