Digital Tv Tuner And Antenna For Cars Is HDTV Supposed To Do This??? (No Pay Service, But I Do Have A Digital Tuner TV)?

Is HDTV supposed to do this??? (No pay service, but I do have a digital tuner TV)? - digital tv tuner and antenna for cars

Ok, juuust my family a new digital television, 42 ", bright, blah, blah, blah. Looks good. And yes, it has a digital tuner.

OK, now ... We do not have cable TV. Or satellite. ... Thus, normally, pay-TV is not completely free (yes, there are a dozen people like me) still on this earth. Basically, we use the roof antenna for the reception.

It does not have an HDTV digital converter box ... But I thought the digital tuner takes care of them.

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Problem ...

Many times - and obviously related to the weather - our image of the TV and sound "jump" at all, like a CD player in your car if you hit a big pothole or something. It flashes and choppy.

I do not understand?? Our previous TV to 100% very well with the front desk. Not a glimmer, nothing.

So it is normal that new HDTV know too well? This would facilitate the establishment of a converter? (remember, we already have a TV tuner).