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enter image description hereI built my first 1:1 CMC transformer recently using 100 ohm CAT5e pairs in parallel. I used an FT-114-43 with 9 turns on each side and squeezed it into a small box with female coax connectors. I plan to use this only with 5 W QRP radio.

The SWR with a 50 Ohm load is good for my intended operation on 20 and 40 meters. I did a quick and dirty check on the rejection using a nanoVNA S21 measurement.

I also need a very light weight dipole antenna for my 5 watt HF mobile rig that will not break my TacMini fiberglass pole.

Can I simply convert the inline choke-in-a-box into a dipole antenna ?

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    $\begingroup$ I'm sorry that your question has gone untouched for so long. I'm also sorry to pick on your post, but it's phrased more for a chat-style forum site than a Q-and-A site, which is understandable because most of us have more experience with forum-style sites. Please edit your post to include a picture of your choke, if you have one. $\endgroup$
    – rclocher3
    Jan 27, 2022 at 14:55
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    $\begingroup$ I took the liberty of rewriting your title in the hope of attracting more attention. I hope you don't mind! (If you do mind, please feel free to roll the edit back.) BTW, please consider writing up your solution as an answer to your own question, and pictures would be great. $\endgroup$
    – rclocher3
    Jan 27, 2022 at 15:18
  • $\begingroup$ I'll update with picks today. The question is really so simple that it didn't make sense. I created an inline 1:1 CMC and wanted to know if this will also serve as a means to attach a dipole antenna directly. $\endgroup$
    – wbg
    Jan 29, 2022 at 17:34

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I'd say that anything that allows you to securely attach the quarter-wave wires, while being light and strong, is a good way to build your antenna. I'd be leery of attaching the wires to banana plugs and relying on mechanical friction of the banana jack and plugs alone. If that's a problem perhaps you could make a strain relief from a piece of PVC pipe and wrap the wires around the PVC to prevent the banana plugs from popping out.

I can't think of an ideal connector to use for such a thing, since very lightweight antennas aren't common compared to heavy-duty antennas intended to last for years. QRPers are ingenious at adapting equipment designed with other purposes in mind, and I don't think any QRPer would look down on a BNC-to-banana adapter.

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Check to see if your BNC to banana plug adapter has caps that unscrew to allow wires without banana plugs to be connected.

Or get a BNC to screw terminal adapter.

Or ger a short piece of coax with a BNC connctor and run the other end into a small box to screws coming out the sides of the box to attach the antenna wires. Then you could put a small eye bolt in the top of the box for hanging on your pole.

The top section of your pole probably won't support all of this, so hang it on the next lower section. Keep your coax tight to the pole with velcro strips or short pieces of wire to take some weight off the top. Sort of like how you support some of the weight of a bacpack with a belt at your hips.

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