For the amateur radio operator with that on-the-go lifestyle, nothing is more important than having your gear as light and packable as possible. If you’re lugging even a modest setup out into the woods, every ounce counts, which is why we love projects like this packable dipole antenna feedpoint.
At its simplest, a dipole antenna is just two pieces of wire cut to a specific, frequency-dependent length connected to a feedline. In practical terms, though, complications arise, such as keeping common-mode currents off the feedline and providing sturdy mechanical support for the antenna to suspend it safely. [Ham Radio Dude]’s design handles both those requirements while staying as small and packable as possible. The design starts with a bifilar 1:1 current balun, which is wound on an FT82-43 ferrite toroid with 22 AWG magnet wire. One side of the balun is connected to a BNC connector while the other is connected to a pair of Wago splice connectors that are glued together. A loop of paracord for mechanical strain relief is added, and the whole thing gets covered in heat-shrink tubing. The antenna is deployed by attaching a feedline to the BNC, clipping quarter-wave wires into the Wago terminals, and hoisting the whole thing aloft. Full build details are in the video below.
People will no doubt be quick to point out that these Wago terminals are rated for a minimum of 18 AWG wire, making them inappropriate for use with fine magnet wire. True enough, but [Dude] was able to get continuity through the Wagos, so the minimum gauge is probably more of an electrical code thing. Still, you’ll want to be careful that the connections stay solid, and it might pay to look at alternatives to the Wago brand, too.
I love prototyping with Wago! I’ve used them for several ham radio projects.
https://www.instagram.com/p/COEpFbajD9z/?img_index=1
https://www.instagram.com/p/CaLjtParjDr/?img_index=1
https://www.instagram.com/p/CkXOwKTjjAe/
Small and light doesn’t need to be that flimsy.
My SOTA setup is similar! It’s a balun piggybacked onto a BNC-to-Banana terminal, feeding a linked dipole. The links are knockoff wagos – they “let go” under just the right amount of force to keep the wire from getting broken. That’s important when you’re using the lightest wire you can manage, and don’t want to bring a whole spool of extra wire.
Type 31 is a FAR better ferrite mix for a choke balun than the type 43 he uses. Type 43 is low loss, which makes it valuable for a transformer but in this application it can potentially form a series resonant circuit with the interwinding capacitance that defeats the choke function entirely. Type 31 is designed to have inherent broadband loss, which of course in this application only (and desirably) exists for common mode currents.
I would build it on a PCB or put it in a 3D printed case. Those wires are going to break off the BNC with a bit of use.