I have been tasked with repairing a Huntron ProTrack I. When I turn it on the LCD displays the name, then says Calibrating Offsets. After that the screen gets a dark line across the top of it and dark lines flash and scroll down it, until the display eventually goes blank. The CRT never turns on as far as I can tell, but voltages are present at the back of it. None of the buttons seem to function either. Any ideas?