John,
If you have sound, but no picture, then the fault could be any number of things.
If you are not a TV engineer or at least have good electronics knowledge, then you will certainly need the help getting this repaired.
If there is no faint raster, then it almost certainly means that you have no EHT (Extra High Tension) which is about 25 Kilo Volts for the anode of the tube which in turn requires all the power supply voltages to be present.
So, any good TV engineer would first test that all the power supply voltages were in place and go from there.
Assuming, there is no raster at all on the screen, then this is unlikely to be a tube fault.