This month marks the 50th birthday of a pretty good idea, as evidenced by the cover story in the August 1970 issue of Popular Electronics. The article was penned by Russ Alexander, W6IEL, who was likely the originator. The article specifically addresses how to use a compact antenna from an apartment, and it makes use of Hustler mobile antennas.

The Hustler antenna is still available today, in more or less identical form. It amounts to a center loaded vertical antenna. The bottom half is a mast that attaches to the car. On top of that is a loading coil, and on top of that is a whip antenna. The loading coil and whip are tuned to a specific band. And because you need different coils and whips for different bands, the coil and whip are sold as a one-piece resonator.

So it’s fairly easy to change bands: You stop the car, get out, and swap out the resonator. But that doesn’t work very well if the antenna is mounted on the roof of your apartment building. And it doesn’t work very well if you want to change bands without getting out of the car.

So the author went to his metal shop, and made a piece which allowed him to mount up to four resonators on the same mast. For bands that are not being used, the coil acts as a trap, so the unused resonators have little impact on the transmitted signal.

The idea caught on. I first remember seeing one of these as a young ham in the 1970s in the parking lot at a hamfest on the car of prominent Minnesota ham Tod Olson, K0TO (then W0IYP). I remember thinking that it was a pretty good idea. Chances are, it originated with the magazine article shown here.

Shown in these pictures is the mobile antenna of W6LEN, an avid WWFF activator of Southern California parks and beaches. He uses the Hustler mobile antenna on a magnetic mount on top of his minivan. While the magnetic mount is probably too small to use in motion, he has had good success with this antenna, and it takes only a few minutes to deploy when he arrives at his destination.  As with the 1970 article, he uses a homemade bracket to mount the four resonators.

Hustler eventually realized that using multiple resonators was a good idea, and they now sell the part, shown at right, so you don’t have to have your own metalworking tools. The author of the 1970 article recommended having the part plated with copper and then cadmium, after which “the finished bracket will look like a commercially marketed item.”  The 1970 Popular Electronics version had room for four resonators, whereas the commercial product has only three wings.  However, a fourth resonator can be added in the middle.