Don,
I'm no electronics wiz by any stretch. A lot of the loaded antennas I've seen had nothing more than an added resistor to make the receiver "think" the antenna is physically longer than it really is. I'm pretty sure this has nothing to do with the antenna's ability to capture the signal and usually hinders it. I guess that is why some have amplifiers. At that I'm still convinced of the "garbage in - garbage out" principle.
Rich