Hi David,
>>Maybe you can disclose at least the the 3dB BW of this kind of antenna?
>Hi Clemens, I'm not sure I understand your question.
The 3 dB bandwidth is f0/Q and Q is defined as X/R
where X is the reactance of the inductor and the capacitor at the
resonant frequency.
The lossless-Q of a small antenna is a useful academic quantity, and is
the reactance divided by the radiation-resistance. It gives the maximum
theoretical Q for any given small antenna, and then the actual Q can be
measured on the real antenna. The radiation efficiency is the lossless Q
divided by the actual Q, by the equations:
Qlossless = X/Rrad,
Qactual = X/(Rrad+Rloss),
Qactual/Qlossless = Rrad/(Rrad+Rloss) = radiation efficiency.
An interesting limit for small antennas is the minimum lossless Q that can
be achieved, and was derived by Chu in 1948 from only the frequency and
the size of the antenna.
73
Clemens
DL4RAJ
>-----Original Message-----
>From: [email protected]
>[mailto:[email protected]] On Behalf Of David Hine
>Sent: Saturday, February 10, 2018 7:13 PM
>To: [email protected]
>Subject: Re: VLF: 1.6 Hz from Kiruna?
>
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