My tv rca

there is loose contact on the high voltage section in your tv.what you are going to do is open it,and reheat  with soldering iron and a piece of soldering lead the video chroma section and the high voltage section,near the flyback

what is actually happening is the unit is loosing the horizontal drive, causing no high voltage. to repair this: be certain the horizontal output transistor is not shorted and resolder the connections on the flyback and horizontal drive transformers and most importantly, the small coupling coil between the drive transformer and horizontal output base lead....this should get the HV back up.....i cannot recall how many of this type i have repaired doing nothing other that that......