*Building A Simple Dipole*
To find the length of a ½ wave dipole for 10-meters you first need to decide what frequency area you will be operating in. Let’s assume that a Novice or Tech + is building this. For voice, they are stuck between 28.3 & 28.5 MHz. 28.400 is center frequency, so that’s what you’d want to use for calculations.
468/28.400 MHz = 16.48 feet. That is the overall length of the antenna. Split it in half and you get 8.24 feet.
You can use practically anything for wire. I use 12 gauge braided because it’s cheap to get and it very strong.
(HINT) If you use black wire, it blends in with trees and surroundings better.
Alright, cut 2 pieces of wire 8.24 feet long. I always install a SO-239 connector on my antennas for ease of swapping out coax. You can just strip back some of the coax and solder the center conductor to one element and the braid to the other. Crude yet effective. If you go this route, be sure to seal it with silicone.
I use a strain relieve at my feed point. Just a small chunk of wood with holes drilled through it. The connector screws to the wood and the elements pass through it. Then there’s no worry of ripping the connector apart if trees start swaying. Notice below how the wire passes through the wood. By drilling the holes at an inward angle, all tension is released from the connector.
Simply solder each element to the connector. After it cools, whop the silicone to it, water intrusion is not a good thing.
Completed antenna
Ok, head outside and string it up somewhere. I set this one up about 6’ off the ground and it was sagging in a V. On 28.4 MHz the SWR was 1.2 As I progressed up to above 29.0 MHz the SWR never went above 1.5
1.2 @ 28.400 MHz
It's easier to tune the antenna by shortening than lengthening. So having the elements a little long is no big deal. I'm anal so I keep my SWR below 1.5 If you're SWR is higher on your upper frequency, (28.5) shorten the elements (1/2" to a time). If SWR is higher on the lower frequency (28.3), lengthen.....I hope not. When you're done tuning dab the ends with silicone.
My elements are actually 94" long. Just a little under what the calculation came out to.
73’s
Jaden
www.alpharubicon.com
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