Erm........ that's a bit like saying a dinner plate receives the same signals.......... or your Avic GPS receives the same signals. They both do, of course, but the thing is, they won't both neccessarily work. Different types of radio/micro wave transmissions require the (same) appropriate antenna to gather the signal before it's processed by the receiver. So I still think what you said is wrong, but if I ever see a car with a dinner plate attached to it's roof, I'll have a pretty good idea who is driving
Wiretap is 100% correct on this. A tv antenna with the same reception characteristics is the same regardless of claims to be 'HD' or otherwise. All you're looking for is for it to be tuned to the appropriate frequency range and have the correct focus type (omni, directional, etc) and adequate gain. An antenna with higher gain will have a narrower focus. The advertising claim of some antennas to be designed for HD or digital purposes is complete garbage. The data coming across the antenna has nothing whatsoever to do with its design.