In the past, I had a 180 feet low Beverage (~3 feet) terminated in 470 ohms facing about 340 degrees. Antenna wire was THHN stranded fed to a transformer to 75 Ohm coax. It was quiet and worked. But it was 'facing' North so somewhat limited. I was also using a crude vertical at the time.
Then I put up a proper multi-band quarter wave vertical. Still quiet and omni-directional. I could hear much more than the Beverage, including noise, especially in the lower bands. The Beverage and crude vertical came down at this point and I used only the quarter wave vertical.
I have gotten to the point where I would like some directivity, especially in the lower bands. I have a HOA lot, so towers are out of the question.
To keep it stealth, I'm going to try a 4-way BOG array, that will be far shorter than ideal. I’ve had decent results with 180 feet. And, this is a RX only array.
To implement all four directions, I need a little over 1,000 feet of coax. I currently have about 600 feet. The feedlines eat up much of the coax since there are two equal lines per feedpoint. My longest run will be for the E-W Beverage, 400 feet of feedline. I will start with the E-W leg since I have everything I need to start on hand.
Also, it may easy to test F/B using WWV to the West. I should see a signal decrease when listening to WWV on the East leg compared to the West leg. Maybe I’m wrong or my F/B will terrible.
Having issues posting images to the forum so here is a link for the time:
https://gr0undplan3.staushbrews.com/HFU/BevArray/BevArray.MAP.jpgThe lengths listed above are the total length of the coax. The feedline run measures to just over 200 feet (x2). Sections D, E and F will require connecting each section into the total 218 feet. Not certain how I will join those sections yet.
The reversible BOG is based on section 2.15.5 in
ON4UN’s Low-Band DXing. Excellent book with an excellent section on receive-only antennas. The concept is based on using both the braid and center conductor as two separate wires. 2:4 transformers wound on binocular cores are used at each end to terminate either the center conductor, or the braid.
Since my ‘wires’ will be on the ground, Z
SURGE is estimated to be 300 Ohms. And I’m using 75 Ohm coax and my transformers (T1 and T3) measuring between 305 and 308 Ohms.
The feedpoint contains both the feedpoint to the shack (2X) and the other 2:4 transformer for the antenna section. Gas discharge tubes (GDT) to ground rods are used at each end for lightening protection.
https://gr0undplan3.staushbrews.com/HFU/BevArray/BevArray.ETU.jpgThe end termination will go on the West leg and the feedpoint/termination will go on the East leg.
https://gr0undplan3.staushbrews.com/HFU/BevArray/BevArray.FEED-TERM.jpgI’m currently getting rain at the QTH and I’m hoping to get the E-W leg installed externally this week. Much easier to pound ground stakes into soft ground. Not much rain recently and very dry.
I’ve also built an entrance panel with GDTs and braid-breaker transformers on each line. More on that to come as this progresses this week.
Thanks for looking.