After Modeling This Antenna I Have Came To The Conclusion That It Would Be A Massive Waste Of time And Energy - Will Upload EZNEC Data Later

002b46d403f93d486c9e547f477dfb94.jpg I have been reading and studying the article - "The Long Wire Loop: an Omni Directional, Multiband, Low Angle Radiator Wire Loop Antenna" by Steve Cerwin, WA5FRF which I have uploaded here for all to be able to learn from and have decided to make my next antenna project the 1,100 foot +/- 160m long wire loop in a 40° triangle configuration. Based on the EZNEC performance data presented by Steve I can clearly see why the 500 foot 1 wave length 160m sky loop that I had up once before was not the performer I thought it would have been. 

The problem I experienced with my previous attempt at a loop antenna stemmed from the lack of the harmonic properties the loop would have exhibited at twice the wave length to create a null above the radiated signal, thus lowering the take off angle immensely, making it a much better DX performer as well as not being the "cloud warmer" that the 1 wavelength version exhibited even when rag chewing locally (600 to 800 miles or so). I eventually took the loop down and focused on my 160m doublet dipole which was reported to me as being a much better performer. 

Today I am still using the 160m doublet at about 75' to 80' at the apex and being fed with 150 feet of 600 ohm ladder line all the way into the shack and terminating at the tuner. It works reasonable well but the data shows that the harmonic loop will outperform the dipole with even lower angles of radiation, and the impedance match will be a comfortable 20 to 200 ohm (easily tuned by either the Dentron Super Tuner or the Palstar AT2K). 

The photo above is a depiction of the 160m doublet dipole that I already have up as well as my planned path for the 1,100' loop in the (approx) 40° triangular formation. Although I have 5.56 acres of land to play with, the tract is relatively narrow so making it fit within the confines of the property boundary might be a bit tricky however it is also heavily wooded which should hide it from even the most eagle eyed. 

Hopefully I can get this done before winter rears its ugly head .....  



Forward To The Corrected Models


Results from EZNEC with the 1100 feet delta loop (sort of) vs my existing 160m Inverted V at 75' height and 240' long



Side by side comparrison of the model and then graph

160m Doublet 240 feet Long  1100 ft Delta Loop 
 160m Doublet 240 feet Long 02  1100 ft Delta Loop 02



By the models presented above it seems to show that although the doublet in an inverted v configuration at 75' seems to show a slightly better low take off angle although it falls short of the delta's purported 6.14 gain by just a little over 2db. You may also notice that looking at the graph on the horisontal plane (red) the doublet creates quite a larger overall radius in pattern as well as a more uniform current prediction with the highest current being towards the middle two thirds just as I have read about before. The model seem to have proved that right.

In order for me to create any extremely good low angle of radiation from the doublet I had to raise the apex to approx 240' (1/2λ), a height that is simply prohibitive in the real world and in my case. I should also note that any and all tests that I did with radials below the apex of the doublet (no matter how many or how long) did not alter the pattern save for the least little bit. An absolutely out of the question endeavor considering nothing to be gained. 




 Corrected Model For 1100' Loop

Current  Radiation  Pattern 



Any corrections would be most appreciated.









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