Comparison between “on ground” and “underground” coax

Days of work and testing here at HamTenna station, taking advantage of the sunny days of the Swedish summer.
In these days I  took the opportunity to also bury the coaxial cable of the 110m long wire.

Below is a comparison between the response on the 1-20MHz spectrum of the longwire with the cable placed on the ground and buried 20cm :

 

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