Yagi feed idea

[brandon7861]

The goal is to direct feed a driven element that is bonded through or welded to the boom rather than isolated from it. To avoid driving a short circuit, what would basically be a slot antenna is cut in the length of the boom so that the boom appears as an open circuit looking up and down the boom from the feed point at the driven. How would the slot antenna affect the pattern of the yagi? Could I treat it like an insulated driven and hairpin match it like normal?

Thanks!

Edit: and if that works, can I simply incorporate the hairpin into one side of the slot antenna?

 

[HarryUSA]

Interesting idea for a dipole, but then if it were just a dipole, you'd call it a dipole with a hairpin match, as for using a slot style antenna as your hairpin, I don't think that would work, at least not without doubling the length of the RF current path so that the "slot" doesn't radiate, but instead acts like a balanced line, where when the currents do finally encounter each other, they do so at at a high impedance-voltage loop, and the only place the RF current can radiate, is the low impedance of the 1/4 wave length radiating elements. But this seems like a lot of work just to make a boom that doesn't radiate. And I'd say if you are building a Yagi, and putting additional elements off of your balanced feed (that being your slot/hairpin matching stub), you are creating more active elements, each with their own complex impedances.

It would be interesting to model in software, and that should be where you start, but intuitively, I'm going to say that as with any other beam antenna design, at a minimum, you will probably need to insulate the driven element from the directors.