The Antenna System
Amateur and CB antennas are not restricted in the RV Resort (mainly because I sat on the committee making the rules) but I wanted to be reasonable with my antenna system. After all, the rules can always be changed.
Since I'm in the business of making antenna systems, it was difficult to choose someone else's product for my station. In fact, I had originally planned to use a 22' whip and build a tuner to mount on the piling just below the antenna mount. However, following the KISS principle, I decided to just go with a trap vertical and accept the compromises. Choosing the vertical was not all that easy. My criteria was somewhat different from that of an antenna I'd choose for my home station. First, the water in the bay is brackish, so the antenna would have to be able to withstand the corrosion. This meant that all those fancy verticals with all sorts of pieces hanging off them were out of the question. They wouldn't last a month in this environment. Oh, and I forgot to mention the salt spray from the ocean which is only a couple of hundred yards to the east of the trailer. Second, the antenna had to be self-supporting. Guy-wires where out of the question. As it worked out, I had to modify the selected antenna to give it enough strength to survive the winds which can reach 50 M.P.H. during summer thunder storms. The third requirement was, 80 - 10 meter coverage with the ability to handle the output of a linear, and fourthly, I wanted a very low visual impact. This place is too nice to spoil the view even with antennas. As you may have noticed, if you checked out the sunsets, the vertical antenna appears in almost every view. It was my purpose, in most of these photos to show the antenna installation and location as well of the sunset. This is the view of the setting sun from the RV's patio.
After all these considerations, I finally decided on a Hustler 6-BTV. This antenna met all of my criteria except for the guying requirement. I didn't see any mention of a guying requirement in the ads! Anyway, a call to the factory netted a suggestion that I reinforce the base section with a wooden rod which I did. We'll see if the antenna survives the winter.
To add further corrosion protection, I painted the entire antenna with clear Krylon paint. The ground connections to the antenna's mounting base are already showing corrosion, so I will have to clean that up and find another solution next summer.
I seem to get out very well from this location using only the vertical. Of course, the excellent ground system helps as does the location. With the Atlantic Ocean only a few wavelengths away to the east and with the antenna sitting over the bay water with the way clear for at least a couple of miles from the northeast to the southwest, I anticipate really excellent results. The computer models show amazingly low takeoff angles on all bands. I'll let you know how it works out because most of the odd jobs are done now and next summer (1998) I should be able to put in some serious time on the air.
This is not the most flattering picture of my QTH at Outdoor Resorts of Virginia. The truck and utility trailer, along with all the junk sitting around are there only because of the modifications and installations taking place. This is a work week. I have just brought in a trailer load of 2" rope to use for decorating the dock pilings and to make a rope fence between pilings. It is during this week that I, with the help of my son Jamie, built the hamshack into a closet inside the trailer, installed the vertical antenna and its elaborate ground system. You can't see my son's boat tied up to the dock because we are in it taking picture. Unfortunately, the roll of photos featuring the more usual and casual life-style with the awning down and burgers cooking on the grill as neighbors stool by was lost by that famous neighborhood discount store whose initials are Wal-Mart.
When you have a place on the water, especially slightly salty water, one obvious idea comes to mind - "I wonder how a vertical would work sitting over water with an elaborate ground system installed?"
The ground system consists to several hundred feet of 1/2" tinned-copper strap. There are two runs along the bulkhead. I have 75 feet of frontage on the water, so there is a 75 foot run of strap one foot above the average water level and a second 75 foot run one foot below the average water level. The idea was to have one of the grounds either in or near the water at all times. There are times when the bay empties out and there is no water for a hundred yards, but that only happens once or twice a year. Most of the time one of the bulkhead ground runs is underwater.
Actually, there is always some contact with the water unless there is no water because the ground straps start at the base of the vertical and run down the sides of the pilings to the bottom and then back up the other side of the piling. Since we land boats at the dock, the ground straps had to be run under the dock until they reached the bulkhead. The ground straps are bonded with another 1/2 inch tinned-copper strap which runs all the way to the shack. There is a ground rod driven into the soil where the tinned-copper strap terminates and a 1/2 inch, tinned-copper ground-braid is routed on into the RV and the hamshack. The ground-rod was the hardware store variety and all traces of copper eroded after only a few months. I'll replace that rod with either stainless steel or pure copper when I install the remainder of the ground system. As a final step, I plan to run copper wire completely around the cement pad the trailer sits on as well as running a length of copper in the soil along the bulkhead. However, I want to see how everything survives the winter because I may have to go back to the drawing board if everything becomes uselessly corroded over the winter.
So, the final results is a very effective ground system. I hear station clearly at this location which are far weaker at home even though I have better antennas there. All of you who have enjoyed an ocean QTH have certainly had a real advantage over us city-dwellers!
|You must think that I'm into sunsets. I am
and that's probably because I never witness sunrises. I'm a night-owl so
this is one part of nature I can enjoy.
Here is a picture of the antenna shown against the backdrop of one of our nicer sunsets. Click on the pix to get a better view.
Shack at the beach