sega rally 2 deluxe
 

hi! does anyone have any experience repairing these arcade machines?
this has a 3 gun projection screen has vertical collapse r,g,b line across
screen i have removed and soldered scan coil pcb and tested coils with meter
all are ok have checked deflection cables etc ok all i can think is that the
vertical deflection pcb which has an stk ic on it is faulty can anyone help?