Can i use a dvd recorder instead of a dtv converter?

This might be a dumb question, but I heard on TV that you could use a DVD recorder as a dtv converter for getting digital television channels. Is this true, or will it need some kind of modifications? My TV is pretty old, maybe 5 or 6 years old, so I'm sure I'll need something.
I wonder, how successful would it be to get handy with a soldering iron and just replace the old NTSC tuner in any old TV, with a new ATSC tuner, voila! Instant DTV.