Can anyone please tell me how to get the test grid up on the Seleco SVT150, I have moved the switch to the on position but nothing is displayed. I have had this machine given to me it was very clean on the outside but is dirty on the inside. I have also tried to get hold of the manuals but without any luck. I have seen this CRT working prior to it being taken down but I am now having a major problem with the red CRT (the image does not seem to want to line up with green! Can anyone help.