[TowerTalk] Coax Grounding on a tower.

ersmar at comcast.net ersmar at comcast.net
Tue Jun 27 10:47:32 EDT 2006


     Photo H in Bob's collection is similar to how I raised my Bencher Skyhawk into position on the tower, i.e., nose upwards.  The principal difference between our approaches is that I used two rope lines as tracks for the Skyhawk to ride on the way up the tower.  I fastened them to the top of the tower and at ground level about two feet off the tower base.  I used rebar pieces as stakes for the bottoms of the ropes.  

     In my case, I had trees surrounding the tower location and I couldn't raise the Yagi with the boom horizontal.  It took a bit of finessing at the top of the tower, but I was able to spin the Bencher on two axes to get the proper orientation for bolting to the mast plate.

     BTW:  I used the same approach for my SPG (single point ground), i.e., aluminum angle with barrel connectors and HD nuts (The Wireman P/N 1158 w/ P/N 1164 .)  

     Thanks for your photos, Bob.

73 de
Gene Smar  AD3F

 -------------- Original message ----------------------
From: "Robert Chudek - K0RC" <k0rc at citlink.net>
> Roger,
> Here's a couple pictures of the bulkhead assembly I made for the top of my 
> tower...
> http://tinyurl.com/rc9v2   See photo's D, E, and F.
> At HF there's negligible insertion loss through a couple extra connectors.
> BTW, I'm done fighting the PL-259 soldering issues and going with crimp-on 
> connectors for my Belden 9913 cable. I just ordered a couple dozen from 
> Tessco along with the proper die for my crimper. I'll see how these work 
> over the long run. I never was a crimp fan until I started working with 
> computer network cables and saw how secure the connections really were.
> Also, I run my cables down the inside of the south legs to gain some 
> shielding from the high-noon sun.
> 73 de Bob - K0RC
> ------------------------------
> Message: 5
> Date: Mon, 26 Jun 2006 22:02:13 -0400
> From: "K8RI on Tower talk" <k8ri-tower at charter.net>
> Subject: [TowerTalk] Coax Grounding on a tower.
> To: <TOWERTALK at contesting.com>
> Message-ID: <008301c6998d$b62e8ba0$6400a8c0 at SecondOne>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
> Due to basement work I've had to pull all the cables out of the conduit.
> Man, but I was sore the other day and was wondering whey until I realized
> I'd pulled between 1300 and 1500 feet of cable out of conduit the previous
> evening.
> This has put me off-the-air with the main station which is probably why
> 6-meters has been open the last couple of weeks.
> As this is turning into a rotator repair (It's hanging up again and the
> thrust bearings are free), antenna repair, antenna removal, replace the pig
> tails, and reroute the coax project I've decided that as long as the coax
> has to go through connectors at the end of the pigtails at the top of the
> tower I'm going to mount an aluminum angle across the face of the tower with
> 3" UHF feed throughs.  Each of the current 4 pig-tails will fasten to a feed
> through which will ground the brade to the tower at the top. The cables then
> run down the inside of the NE tower leg where they are joined by two more to
> the base and loop up into the junction box where they enter the 3" conduit
> to the house.  The cables will be jointed by at least one or two more part
> way down the tower, but there may be two less from the top.  The easiest is
> to just say the number may vary.
> My thoughts are to either use another set of bulk head connectors on
> Aluminum angle bracketed to the tower as at the top, or to clamp those
> brackets to the leg of the tower using a hose clamp and spacers so the
> center part of the feed through will be grounded to the tower leg.
> This will add one more set of connectors to the cables but from experience
> and information gleaned from TT I'd say the insertion loss of the one extra
> connector is going to be almost non existent. In addition the cables will be
> grounded to the tower where they are leaving the tower.
> The new junction box at the house entrance will be putting the shield
> grounds and the Polyphasors (sp?) right outside  the house at the point of
> entry where they are currently just inside the house.  I think this will be
> an bit of an added safety feature.
> One leg of the tower ground system will be entering the Hoffman box beside
> the conduit, grounding the back plate inside and then continuing into the
> house with the other cables. This #2 runs directly through to the house
> ground for the electrical service as it's the only way I can get it there.
> I'd have to tear up a rather expensive garage apron to get there outside and
> that would make the grounds different length.
> This is going to get rid of the conduit coming through the basement wall.
> It'll come in through the end plate of the floor joists and there will be no
> cables showing below the basement ceiling.  At least that is the plan.
> Remember it's normal for this installation to take at least three lightning
> hits a year and I think it's already had it three (or more) just in the last
> storm.
> Any socially acceptable suggestions?
> Roger Halstead (K8RI and ARRL 40 year Life Member)
> N833R - World's oldest Debonair CD-2
> www.rogerhalstead.com 
> _______________________________________________
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk

More information about the TowerTalk mailing list