You could also do a vertical dipole the way k9yc did…
Feed it with coax that forms the bottom half and use a choke to set the
electrical length of the bottom 1/4-wave.
He has a more detailed description on his site.
73, kelly, ve4xt
Sent from my iPhone
> On Jan 12, 2026, at 23:17, Tom Hellem <tom.hellem@gmail.com> wrote:
>
> My hat is off to all of you fine gentlemen who contributed to this
> discussion.
> You have helped me see the light.
> I think the reasonable conclusion is that a center fed vertical dipole is
> a very difficult thing to make work, especially if the feedline cannot be
> brought away from the antenna horizontally for an appreciable distance.
> I’m going to try base feeding it with an LC network and see if I can get
> better results.
> Many thanks to everyone who provided input.
>
> Tom
> K0SN
>
>> On Mon, Jan 12, 2026 at 6:57 PM Jim Brown <jim@audiosystemsgroup.com> wrote:
>>
>>> On 1/12/2026 5:23 PM, Jeff Blaine wrote:
>>> Tom, I'm emphasizing what Jim mentioned earlier. If the antenna
>>> resonant point moved by adding the choke, then that means the feedline
>>> was participating to some extent as "part of the antenna."
>>
>> Yes, but in Tom's configuration, even with the world's greatest choke,
>> the feedline can still be a parasitic element.
>>>
>>> My belief is that without a feedline choke, you simply cannot guarantee
>>> that the feedline will not participate. So every antenna here (19 of
>>> them) has a feedline choke of some form.
>>
>> Yes. And feedline chokes also reduce interstation interference, whether
>> SO2R or multi.
>>
>> 73, Jim K9YC
>>
>>
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