Aha, Joe is right!
Sorry, I assumed Low Band.
Sometimes it helps when one can READ! ☹
NO PROBLEM:
https://www.dj0ip.de/vertical-antennas/80m-on-12m-pole/
Here you will find the typical lengths for 80m.
Of course lengths vary slightly from one QTH to the next.
The Top-Hat wires are about 20 ft. long. Same rules. Use thin wire for the
top-hats.
73 - Rick, DJ0IP
(Nr. Frankfurt, Germany)
May the Sunspots be with Us!
-----Original Message-----
From: Topband <topband-bounces+rick=dj0ip.de@contesting.com> On Behalf Of Joe
Subich, W4TV
Sent: 11 April 2021 14:36
To: topband@contesting.com
Subject: Re: Topband: 43’ 80 Meter Vertical
On 2021-04-11 5:25 AM, Rick@dj0ip.de wrote:
> Let's put this in perspective: for the short pole Bob is using, the
> top-hat wires are going to be in the neighborhood of 100 ft. long.
> So we do need a lot of space for this.
That is for 160 meters. Bob is building for 80 meters (3545 KHz) so use the
info here:
<https://www.dj0ip.de/vertical-antennas/80m-on-12m-pole/>
73,
... Joe, W4TV
On 2021-04-11 5:25 AM, Rick@dj0ip.de wrote:
> I agree with Rick; its better to use 4 top-hat wires.
>
> On my Vertical Antenna page, I originally showed plans for verticals with 2,
> 3, and 4 top-hat wires.
> I now only show the 4-wire version, except for the Inv.-L.
>
> Let's put this in perspective: for the short pole Bob is using, the top-hat
> wires are going to be in the neighborhood of 100 ft. long.
> So we do need a lot of space for this.
>
> The more top-hat wires, the shorter they need be.
> But try to keep them equally spaced around the pole and at equal heights.
>
> And, if space is an issue, the only solution is a longer pole.
> For instance, with the 60 ft. Spiderpole, the 4 top-hat wires are only about
> 82 ft. long.
> And with the 85 ft. Spiderpole, the wires are about 23 ft. long. (If not
> for darn HOA's . . . )
>
> With these longer poles, the top-hat wires should not exit from the top;
> these poles are too thin.
> Drop down one segment and connect the top-hat wires there.
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt, Germany)
> May the Sunspots be with Us!
>
> -----Original Message-----
> From: Topband <topband-bounces+rick=dj0ip.de@contesting.com> On Behalf
> Of Richard (Rick) Karlquist
> Sent: 11 April 2021 00:35
> To: Chortek, Robert L. <Robert.Chortek@berliner.com>; TopBand List
> <topband@contesting.com>
> Subject: Re: Topband: 43’ 80 Meter Vertical
>
>
> On 4/10/2021 1:16 PM, Chortek, Robert L. wrote:
>> Hoping to get some guidance from the antenna gurus here.
>>
>>
>> Can someone tell me if I added two top hat wires 16 GA THHN sloping at 45
>> degrees “about” how long they would need to be to resonate at 3.545 MHZ.
>>
>> Bob/AA6VB
>> Robert L. Chortek
>
> After SWR, the most overrated goal for ham radio antennas is resonance. You
> should use the amount of top loading that maximizes the radiation resistance.
> Then put an appropriate reactance in series with the antenna to provide a
> resistive load to the transmitter at 3545. The reactance may be turn out to
> be inductive or capacitive. You will also want to make the series reactance
> variable somehow unless you only ever want to operate on 3545.
>
> You would also be advised to use 4 top loading wires instead of just
> two. There is a substantial advantage for 4 vs 2. Beyond
> 4 top wires (say 8) the benefits aren't worth the trouble.
> This is explained by the fact that 4 is the maximum number of top wires that
> don't couple to each other.
>
> It is also advantageous to pull out the top loading wires to a more gentle
> slope if you can.
>
> You can use bare aluminum electric fence wire to reduce weight and wind
> loading on the vertical.
>
>
> 73
> Rick N6RK
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