Hello I'm from Portugal and I have a passion for the arcade, I have a hantarex polo 20 ", but the image is not well, I can not expand it more vertically ( if expand more goes out of the borders) and it is as seen in the images, I tried to regulate the potentiometer next to the tda1675a but does not change, the chassis still have not changed the capacitors, does anyone know which component regulates the size of verticality of image? sorry for my English