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Technical Topics => Equipment => Topic started by: ultravista on August 12, 2021, 1441 UTC

Title: Random Wire or Large Loop and Height?
Post by: ultravista on August 12, 2021, 1441 UTC

I have the space to run a random wire (+500 foot) and would like advice whether the same length configured as a loop would provide benefits?

Does the same length of wire configured as a loop provide any value vs. running the wire in (semi) straight line?

Also, I can easily add ceramic insulators to my trees at a height of 15-20 feet. Higher than that will be problematic.

Does a height of 15 feet vs. 30 feet provide a perceivable impact?

Title: Re: Random Wire or Large Loop and Height?
Post by: ChrisSmolinski on August 13, 2021, 1328 UTC

You have a few options, depending on your space:

Run the wire in a straight line as long as you can. Terminated, this is the classic Beverage antenna (search on this board for prior posts about this antenna, how to feed and terminate it, etc). It will be directional towards the far, terminated end, opposite the feed point end. Left unterminated, it will be directional in both directions. Beverage antennas are typically run 6 or 8 feet above the ground.

Run in a large loop, this is the classic Sky Loop antenna. Make it as large in perimeter and enclosed area as you can. Also search for posts here about this antenna type. A sky loop antenna's directivity is often unpredictable due to many lobes and peaks, especially as you go higher in frequency. With sufficient hand waving, you can assume it is mostly omni directional with those unpredictable variations.  Height generally helps improve low angle reception, but even 20 ft will "work".

I have both Beverage and Sky Loop antennas here, they both work well, for different applications. Again, some searching here will turn up many prior posts and discussions.