Here is our shack and antennas as of February 2008
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Our operating position.
Left to right. Home made switch box so I can switch all my antennas
(except the discone) between my 2 main radios.
My book case radio rack top to bottom. The radio on the top shelf
is a Motorola 5000 series, 800Mhz public service radio from Campo Fire, part of the San Diego County Regional Communications
System. See my main page for links.
Top of the house. No Name Discone and 900Mhz wireless LAN transponder. Diamond Discone. 11M whip. Diamond 6m/2m/70cm.
Cushcraft R7000 40M th 10M vertical. Mounted about 50 feet South of the house. With 60 MPH + wind gusts during the Santa Anna winds we need lots of guy wires up here.
My latest, Feb. 2008, fun antenna project. A 160M Carolina Windom. Located South of the Cushcraft. Our retirement home is on 8 acres, 500 x 1000 feet so I had plenty of room to put up a full length 160 Meter antenna. The guy wire coming off the top left of the antenna is moved towards where ever the current wind event is coming from.( Update: I now have 4 guy wires so I don't have to move the one anymore when the wind changes.) Below are some details on the construction. The wire is a FLEXWEAVE™ 14 AWG with extra tough Black Polyethylene jacket from the wireman.com. The formula to compute the length is the standard 468/frequency with the 4/1 Balum at 62.2% from one end.
With Xena Warrior Princess in the background this is the center support structure for the Windom. The wood is a 4x4 pressure treated buried in 360 pounds of post hole mix. This bottom section of the mast is the top rail material used in a chain link fence. From the bottom to the top is 37 feet of assorted pipes and TV masts from our local East County Lumber. I just kept sliding stuff together till it looked like that was as high as I could get without the winds blowing it over.
Up and down the 4x4 post are 4 of the brackets designed to hold the chain link fence to your support pole, that is if you were actually building a fence with it. This top one makes my pivot point so I can drop the antenna. The next one down is 90 degrees from this one and so on down the pole. This pulls the mast tight against the 4x4.
I think next time I will put in a taller 4x4 to give me a little more leverage. Behind you can see the position of the Windom in relation to the house. The feed line is fed underground through PVC pipe.
Here is the 4/1 Balum mounted to a 12" shelf bracket with a chain repair link to hold it away from the top of the center pole. The shelf bracket is screwed to the mast. I don't know if this is necessary but it seemed like a good idea as the Carolina Windom uses the vertical feed line as a radiating element.
Above is my answer to a common mode choke. To see the discussion on how I ended up with the above go to my saga of the Balun page.
Here is the base for my 20' end poles. The PVC pipe is held in place with 120 LBS of post hole mix. I use 2ea guys in addition to the antenna wire to hold the end poles up.
My end pole guys are attached to one of those steel stakes they use to hold up concrete forms. With decomposed granite as my ground they stay in place. With soft ground you may need some concrete. Note my liberal use of chain repair links to tie the dacron guy wire to. I also use them to hold the pulleys on the end poles to hold the antenna wire up. So that's the latest from Campo. Hope you enjoyed checking out my projects Craig Williams W6CAW
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