For this weeks project, we will be building a 1/4 wave ground plane antenna. This type of antenna is very easy to build and I recommend all beginners to give it a try. Many hams use a SO- 239 chassis mount connector. You can solder the radiating element directly to the connector and use the mounting holes for the ground plane
I want to try something a little different than the typical ground planes you see. Instead of using solid copper or tubing, I was curious how stranded wire would perform. Using stranded wire would give me the possibility of using this antenna portable. There is also the advantage of rolling it up and storing it easily.
There is a ton of 14 gauge thhn wire lying around the shop. The RG-58 is from a past project and is being repurposed. The enclosure is 3d printed.
First, cut the elements to length. This antenna will be for 146 MHZ. There are many calculators on the web if you want another frequency. I have listed a site that has a calculator and some other nice projects on it. For this project the radiating element will be 19.21 inches. The ground plane elements will be 21.51 inches. Cut the elements a little long just in case. If they are to long, excess can be cut while tuning.
After feeding all the wires through there holes. Solder the ground plane radials to the outer brade of the coax. Solder the center conductor to the radiating element. Use heat shrink to keep solder joints from touching. Tuck wires in neatly and install the cover.
Loop the end of the radiating element around the insulator. Do not secure to tightly. During tuning, you may need to adjust your length.
To keep the ground plane separated, I cut 2 pieces of ceiling grid wire 30″ long. Unfortunately, I ran out of daylight and was unable to tune the antenna. A quick test showed that without any tuning SWR was not to bad. During the week I will tune this antenna and do a functional test. There will be an update post after testing.
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