[TowerTalk] Fw: Feeding single band HF yagis 500+ ft from the shack

Wes wes_n7ws at triconet.org
Tue May 17 14:54:57 EDT 2022


I have no idea of what the towers and antennas are in this installation, except 
there seems to be more than one and there will be monoband Yagis installed.

I've already stated that I think OWL is a mistake, so what are the options?  In 
my case, I have a modest 45' tower with a small triband Yagi and a couple of 
wire inverted vee dipoles.  The tower is about 150 ft from the shack and I run 
7/8 Heliax to the tower for the tribander and 1/2 Heliax for the dipoles.  
But... I bought this stuff as reel ends years ago and paid $100 for the 7/8 and 
who knows how much for the 1/2".  I bought the tower and rotor used for $300 and 
put it up myself 20+ years ago.  If this tower was 500' from the shack and I 
wanted to run 7/8 Heliax today, the cost would be comparable to the whole 
installation.

Contrast this to a couple of local friends who have super-duper motorized 
Tashjian towers and ginormous rotors spinning huge Steppir beams.  They have 
$25-30K in these installations.  In this case the cost of 500 ft of 7/8" (Heliax 
AVA $3.81/100 at Tessco)) cable adds about 10% and 1 dB loss @28Mhz.

I know that we are programmed to want big coax for long runs, but consider 
dropping down to 1/2" Heliax.  The cost is about 40% less ($2.30/ft at Tessco) 
and the loss is only 1.7 dB @28MHz and proportionally less at 20 meters.  In 
fact on 20 meters, you would be hard pressed to tell the difference.

Wes  N7WS


On 5/16/2022 3:39 PM, dave arruzza via TowerTalk wrote:
>   To all...
> I have a new QTH and the towers for the monoband yagis will be 500-600 feet away from the shack.
> I remember reading about utilizing 2 transformers and open wire line to minimize loss.
> One transformer at the tower base to transform the yagi coax to open wire.
> A run of open wire line to another transformer at the shack end.
> Then coax to the shack.
> I know that I can buy hardline to accomplish this but that becomes costly.
> 73 Dave W1CTN / 4
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk



More information about the TowerTalk mailing list