Dipole is 2 x #12 AWG copper twisted, redials are 1/8" aluminum welding rods.

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Here are the results:

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I was shooting for a resonance of 146.520, but I really didn't want to cut any more off of the dipole.  I won't be able to put it on the mast until next weekend to see how it performs.

I built one a few weeks ago using steel rods as the radials and ring terminals to attach them to the SO-239.  The weight of the radials caused the ring terminals to bend too much and they are hanging at about 60 degrees rather than the preferred 43 - 45 degrees.

Looks good!  Some thick-walled and glue lined heat shrink around the thin part of those ring terminals might stiffen them up a bit to help with the bending.

Also, just a point on your use of the word "dipole" here is incorrect.  What you're describing is the radiating element.  A dipole is a type of antenna, and in a manner of speaking the entire ground-plane antenna is a type of "dipole", the radiating element is one "pole" and the ground plane is the other.


ETA: scan the SWR up on the 440 band as well, you might find it has a decent resonance point around there since it's about the 3rd harmoninc of 2 meters.  It wouldn't have great low-angle gain on that band, but it would be usable.

I built one very similar back when I was licensed.

I had a Kenwood handheld and the performance on 5 watts was impressive.

EDIT: I think I even twisted the center pole like you did, but I left a small loop at the top so I could tie a string/rope to it and hoist it up into a tree.

Very nice. Now you can build a version 3 that is even better, since your confidence level that you know what you are doing is at maximum

Did you see my folding quarter wave vertical thread? A brass or aluminum rod, with the end turned or ground down to fit into the center conductor of the connector, will be much more robust. In fact, why not use the welding rod you have?

I tried soldering the welding rod to the base of the SO-239, and no go, melted the teflon insulator.  So I ended up using JB Weld.  It certainly would not have soldered to the center pin.  Maybe a brass rod?

I tinned a brass rod, tinned the center pin, used lots of flux, and had no problem.

I used 12 gauge solid wire for my first one.

It worked pretty well.

How long is the vertical element OP?

19-3/16" more or less

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I thought it looked longer than that.

One small niggle ......... that is not a "dipole" it is a quarter wave with a ground plane.

The radials droop to make the feed impedance more or less 50 ohms.

You might screw around with that angle and see how it affects the SWR,

Once the antenna is resonant, farting around with the impedance may improve the match and reduce the SWR even more.

(do this at the resonant frequency)

I made one for 2 meters, 220 and 440 a few years ago. I used brass brazing rod. Soldered the radials to a chassis mount 239. They worked great! Handy to have when portable or an emergency.