NOISE ADVANTAGE OF LONG WIRE ANTENNA FAR END TERMINATION

Useful information regarding antennas for SDR products.
glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: NOISE ADVANTAGE OF LONG WIRE ANTENNA FAR END TERMINATION

Post by glovisol » Tue Jun 11, 2019 8:02 am

NEW Vs. ORIGINAL ANTENNA TERMINATION - COMPARATIVE RESULTS, 3.6 MHz

Guys, I apologise for always posting diagrams, diagrams....but cannot be helped. If one converts the raw measurement data shown in these diagrams and compares with his own data, he can very well understand what is the noise class of the site he is in and maybe how noisy his antenna is.
Attachments
Noise floor compare 3.6 MHz.jpg
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sdrom33
Posts: 128
Joined: Sun Dec 09, 2018 4:38 pm

Re: NOISE ADVANTAGE OF LONG WIRE ANTENNA FAR END TERMINATION

Post by sdrom33 » Wed Jun 12, 2019 4:38 am

What you mean by "convert".?

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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: NOISE ADVANTAGE OF LONG WIRE ANTENNA FAR END TERMINATION

Post by glovisol » Thu Jun 13, 2019 11:49 am

NEW Vs. ORIGINAL ANTENNA TERMINATION - COMPARATIVE RESULTS, 7.2 MHz

Hi sdrom33, "convert" means converting the raw measured noise data on the power meter of the RSP receiver into the standard ITU value, to classify the noise level in one of the ITU categories, as explained in my thread "assessing the performance of the RSP receiver system in HF":

https://www.sdrplay.com/community/viewt ... f=5&t=3685

But even if you are lazy, the comparative data presented in the graphs shows the advantage obtained by modifying the antenna terminations. Even if in some points past levels seem better on a spot, the improvement on average noise level is quite noticeable. Please understand, as already explained, that the noise advantage becomes bigger when man made noise is effectively present and man made noise level tends to decrease with increasing frequency, so the best advantage was obtained in the lower HF. In the graph below, ignoring the big variations of October 2018, the advantage obtained in June 2019 over November 218 on 40 m is immediately apparent .
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Noise floor compare 7.2.jpg
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glovisol
Posts: 662
Joined: Thu May 10, 2018 6:42 pm
Location: Piedmont, Italy

Re: NOISE ADVANTAGE OF LONG WIRE ANTENNA FAR END TERMINATION

Post by glovisol » Sat Jun 15, 2019 6:24 pm

NEW Vs. ORIGINAL ANTENNA TERMINATION - COMPARATIVE RESULTS,14.2 MHz
Attachments
Noise floor compare 14.2 MHz.jpg
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