1) No video or sound in internal tuner mode.
2) I do heard the sound from my VCR connected to the TV when I switch the input to line input mode.
3) I can hear the slight "buzz" of the power supply when I turn on the TV.
The fact that I still have sound through the TV's speakers in line input mode tells me either I have a blown fuse, a blown capacitor or the tube is dead. Do CRT TV's have multiple internal fuses? If they only have one protective fuse, I wouldn't get any signs of power on the TV in the first place.
If you are thinking about fixing it, get it evaluated at an independent TV repair shop. They can fix TV's cheaper than an official manufacturer authorized service center.
For example a couple of years ago my parents had a 9 year old 50" rear projection CRT TV whose picture was unstable, and after a while would show no picture at all. I asked the technicians at an independent repair shop if it was worth fixing, and they said that if the problem was what they thought it was, it would cost a couple of hundred dollars to replace a few capacitors on a daughter card. The hardest part was getting the TV safely loaded in the back of an SUV to take it to the shop. They evaluated the TV, cleaned out the dust inside, and determined that the problem was in fact some worn out capacitors. We authorized them to replace the capacitors. They told us that a factory authorized shop would have just ordered a whole new daughter card that cost more than the whole repair cost my dad, and the total bill would have been about double what he paid. My parents have used that TV for a couple of years since the repair, and it works just as well as it did when new.