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Technical Topics => Equipment => Topic started by: ChrisSmolinski on December 13, 2018, 1315 UTC

Title: Some more LoG (Loop on Ground) results
Post by: ChrisSmolinski on December 13, 2018, 1315 UTC
I decoded 40 meter WSPR last night on my KiwiSDR, from 2300-1300 UTC this morning. This is with the 350 foot LoG antenna. Pretty decent results. My next step is to build a smaller LoG again, keeping the larger one, and compare results, especially on the higher bands.

(https://i.imgur.com/aYth3Iy.png)
Title: Re: Some more LoG (Loop on Ground) results
Post by: refmo on December 13, 2018, 2246 UTC
Several nice catches there.  ZB2BU runs 200mw to a 30' wire, on top of the Rock of Gilbraltar.
Looking forward to seeing results with the smaller loop.
Title: Re: Some more LoG (Loop on Ground) results
Post by: Josh on December 13, 2018, 2250 UTC
Is this thing a circular loop, or are you altering the layout to exhibit some directionality? Some log writeups say they lay the wire out in a "dual diamond" config or whatever it is.
Title: Re: Some more LoG (Loop on Ground) results
Post by: ChrisSmolinski on December 14, 2018, 1118 UTC
The 350 ft loop is an irregular rectangle in shape. Time permitting I am going to re-lay it out as a square to increase the cross sectional area.

I set up the smaller loop yesterday afternoon, it is roughly a square 12.5 foot on a side. I made it with a 50 ft section of coax, using the shield, hoping the lower inductance of the large diameter shield vs #16 wire will help.  By the time I got it done, the higher bands were starting to close already, but some quick tests showed it generally produced stronger signals on 25 meters and up, vs the larger loop, which seems reasonable.
Title: Re: Some more LoG (Loop on Ground) results
Post by: ultravista on December 24, 2018, 0141 UTC
Are either loops amplified or run straight to the radio?
Title: Re: Some more LoG (Loop on Ground) results
Post by: ChrisSmolinski on December 24, 2018, 1509 UTC
Straight into the radio (though matching transformers), no amplifiers.