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Author Topic: 13.56 MHz Antennas  (Read 470 times)

k6sti

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13.56 MHz Antennas
« on: June 13, 2021, 0033 UTC »
Four antennas over three types of ground:

http://ham-radio.com/k6sti/hifer.htm

Brian

Offline Prairiedog

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Re: 13.56 MHz Antennas
« Reply #1 on: July 16, 2021, 1657 UTC »
I appreciate what you're trying to do.  Problem is, the results that your page calls "flawed" are far closer to the truth than your "correct" ones. What you term an "invalid" conversion factor and a "technical error" are in reality the international standard for EMC compliance measurements, not an error on ANSI's part or the FCC's.  This is pointed out accurately, if somewhat wordily, in a July 11 post on the subject in the LWCA message board.

Offline Finman

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Re: 13.56 MHz Antennas
« Reply #2 on: October 08, 2021, 1959 UTC »
You need to provide the entire quote...

"Part 15 incorporates ANSI C63.10, which contains a technical error. It says to measure the magnetic field and multiply by 377 to get the electric field. But since the field strength ratio near ground varies widely from this free-space value, the result is invalid."

To over simplify, the point being, "free space value" is not reality in the case of a typical part 15 hifer beacon.


« Last Edit: October 08, 2021, 2001 UTC by Finman »
Right now at the temporary listening post = Icom IC-7610, 130ft end fed sloping random wire into manual tuner.