Towertalk
[Top] [All Lists]

Re: [TowerTalk] tower & antenna project questions

To: "Tower and HF antenna construction topics." <towertalk@contesting.com>
Subject: Re: [TowerTalk] tower & antenna project questions
From: "Roger (K8RI)" <K8RI-on-TowerTalk@tm.net>
Reply-to: "Tower and HF antenna construction topics." <towertalk@contesting.com>
Date: Thu, 11 Mar 2010 21:58:08 -0500
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
This is what I did as far as the conduit from the tower to the house and 
tower to the shop.
http://www.rogerhalstead.com/ham_files/cablebox.htm

73

Roger (K8RI)

ke2d@comcast.net wrote:
>
> Good afternoon.   Finally, the 3rd sunny day in the 50s here in NJ, and time 
> to start the antenna work!  Hopefully we'll be pouring concrete in another 
> week or two for the new tower. Nothing like having a new tower delivered with 
> 24" of snow on the ground!  Now,...... 
>
>
>
> I am looking to purchase a few 6m/2m/440 yagis to stack above my HF antennas. 
>  In my last installation, I used Cushcraft antennas - 13B2 for 144, 719B for 
> 440, and A506S for 6m.   The VHF/UHF will be vertically polarized, as I work 
> more FM simplex than SSB.   6M, however, will be horizontal for SSB DX.   
> This time I am now looking at the M2 stuff, namely a 2M12 for 144, a 440-18 
> for 440, and a 6M7 for 6m.   
>
>
>
> Does anyone have any recommendations of one over the other (Cushcraft vs. 
> M2), or  recommend any other manufacturers for VHF and UHF yagis?  
>
>
>
> Also, I plan to stack a Hy-Gain 7-3 along with a TH-11DX.   I was thinking of 
> placing the 40m beam above the TH11, as the TH11 has the higher windloading.  
>  Anyone have any comments on which should be on top (am I correct in placing 
> the heavier antenna lower?), and also how much distance I should allow 
> between the TH11 and 7-3 40m antenna so as to minimize any potential 
> interaction? 
>
>
>
> In addition, I need to run grey conduit under ground from the base of the 
> tower to where the cables will enter my home.  I need to run 9 coax cables, 
> and a rotor control line. 10 cables total.  Each run will be approx. 210ft.  
> 100ft up the tower, then 50ft from the tower to the house, then 50ft along 
> the basement and up into the shack, then 10ft or so for movement in the 
> shack.   Due to the long runs, I was planning on going to LMR600 type cable 
> to cut down on the losses, especially at  50MHz and above.   I am thinking of 
> going with LMR600 right up to the antennas, making sure to oversize the rotor 
> loop.  I successfully used solid center LMR400 for 10 years, so I might 
> gamble this time again.  The loss figures for LMR400 keep pushing me that 
> direction! Any idea what size conduit I will need if I opt to run 9 runs of 
> LMR600 size cable and one rotor cable?  I was able to easily get 10 LMR400 
> size cables in either 2 or 2.5" conduit (can't recall, as the last tower/qth 
> was 10yr
 s ago).  I stopped at HD and looked at 3" conduit, but damn, that stuff just 
looks too darn big, especially when it will be going into the side of my home. 
I was planning on entering just above the concrete foundation, where there is 
an approx. 8" sill between the concrete and where the first floor rests. Same 
as the utilities do.    
>
>
>
> One other thing - my plan was to run the conduit from the house out to the 
> base of the tower, sink a few 4x4s into the ground near the tower base, then 
> mount some sort of grey weatherproof enclosure on them. Have the conduit from 
> the house go directly into the bottom of the box, then have another elbow 
> come out the bottom, allowing the coax cables to make a drip loop before they 
> head up the tower.  Inside, I was planning to install a copper plate to which 
> I would affix 10 or so Polyphasor arrestors, and the rotor control surge 
> arrestor.  Then bond the plate and tower to common ground rods near the 
> tower.  Can anyone recommend a suitable enclosure that will comfortably fit 
> 10 or so surge arrestors, plus some room to spare. I took a quick look at the 
> DX Eng website, but their stuff only accomodates two or three devices. 
>
>
>
> I also need to install an electrical outlet near the base for the tower 
> motor. So I will be running a 3/4" conduit as well, from the main panel out 
> to the tower base.  Any objection to dropping the electrical conduit in the 
> same trench as the coax conduit? 
>
>
>
> Finally, as far as grounding goes - is there any advantage to installing 
> three 8ft ground rods at the bottom of the tower foundation hole BEFORE I 
> pour the concrete, and run the ground wires up thru the concrete base, to be 
> attached to the tower once it is erect? Or just stick to three ground rods 
> into the dirt around the base of the tower foundation after it is done? 
>
>
>
> Thanks for your insight and knowledge.  I've been learning a lot just reading 
> the postings of the last month or two in preparation for this project. 
>
>
>
> Eric 
>
> K2WD
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>   

_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>