John,
Yes, I would prefer he insulate the elements. Using Hygain element clamps I
would probably use the equivalent diameter calculation from YO.
But first I would see what the effect would be to take a good design for a 20m
Yagi and then change the center 8 inches or so (4” either side) from 1.25” or
whatever it is to about 3.5” diameter. I just guessing, having not looked at
it yet that it won’t be significant since it is a section that’s lnot more than
3-4% of the total length.
If it makes a significant difference he will have to make elements that are
insulated. I don’t like guessing.
73…Stan, ZF9CW
> On Nov 4, 2025, at 8:46 PM, john@kk9a.com wrote:
>
> Maybe easy for you, Stan I have not done well designing multi-band Yagi's
> although I have not tried doing so with AutoEZ. I would be interested in
> seeing your WEQ file for this. Hy-Gain uses a large formed aluminum element
> clamp so you might have to make some guesses for modeling. Insulated
> elements are easier.
>
> GL
> John KK9A
>
>
> Stan Stockton K5GO wrote:
>
> Dave,
>
> This is pretty easy to do. Would probably end up being 3 on 20 and 4 or 5 on
> 15. The difficult part is inputting exactly what the lengths and diameters
> you are going to use for each element. AutoEZ will do the rest of the work
> using one feedline.
>
> If you give me the exact lengths and diameters of the first 3 elements on
> your 20m antenna and same info for what you want to use for the 15m elements,
> I’ll do it for you.
>
> No 10 meters?
>
> Stan, ZF9CW
>
> Sent from my iPhone
>
>> On Nov 3, 2025, at 11:40 PM, dave arruzza via TowerTalk <towertalk at
>> contesting.com> wrote:
>>
>> Has anyone successfully added, non trap, 15 meter elements to a 204ba.
>> 73
>> Dave
>> W1CTN / NC4DARADIO GASTONIA203-906-6209
>
>
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