Pete, do “old fashioned” rabbit ears work? Do they receive a signal even though they aren’t HD antennas?
A decent antenna will work. It doesn't have to be HD specific. An example is the guy who came to hook up my Dish Network. He took a spool of thin gauge wire, unwound about two feet of it, and just shoved it into my "Antenna in" port on the back of the set. He just did it to shows us how the HD Dish signal looked, vs. antenna. Several of the local channels came in loud and clear (regular digital and HD). Some didn't show up at all. All those that did come in had far better resolution than the Dish signal ever gets.