You can receive digital TV with a standard antenna, but you will get stronger signals and more stations with an antenna configured for the new frequency. I am using a powered Terk antenna at present, and some stations break up a bit and more distant ones do not come in at all. An indoor rabbit-ear antenna works rather poorly when you use it with digital signals.
The $56.00 digital tuner is not only unavailable, they want nearly $19 to send it. That is rather a lot more than $50. The best way to get a digital signal would be to buy a DVD or DVD/VHS player with the tuner included. These are mostly available only on line.
If you should venture to a retail electronics store, like Brands Mart, and ask about digital antennas, they will try to sell you a thousand dollar TV that still will only work with cable or dish. They have never heard of digital tuners, or digital radios or digital anything other that "HDTV ready" TVs.
It is incredible how utterly ignorant commission sales clowns such stores are . I do not think many of them could empty piss out of his shoe if the instructions were written on the bottom of the sole.
Of course, I meant that the DIY antenna will pick up a digital signal only by use of a digital tuner. This seemed too obvious to mention to a genius like Ami, who seems to feel we are unaware of his omniscience.