It very well could be the tuner giving the problems. One question though, does your TV have PIP? If so, when you loose the picture, try tuning the set with the PIP tuner. Also, when you say you are loosing the picture, is there snow on the picture? Can you get the menu to come on the screen when you loose the picture? When you are using the VCR, are you just using the coax cable, or are you using A/V cables. If you are using A/V cables, this signal is by-passing the tuner, and the IF circuits.
I'm using A/V cables, so bypassing the TV tuner
It's working thru the VCR, so that's what we'll do for now
No sense spending $$ on a 14 year old TV
My 26" 23 year old TV is still working
And my wife's 20 year old 19" TV
I'd be willing to bet the new LCD/Plasma TV's will not last that long
Especially with zero maintenance
I hate to tell you, but with the experience I have, people will be lucky to get 5 years out of them. They are NOT holding up like the old CRT TVs. Also, one of the biggest problems for some of the flat-panel sets is getting the parts. I have seen where a set breaks down in 10 months, and the parts are already discontinued. Also, with the flat-panel sets, in most cases, you have to replace a complete assembly, not just the bad parts. This means that the new sets can be a lot more expense to repair than the old sets.