Author Topic: B-Field or H-Field?  (Read 594 times)

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Offline miraculon

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B-Field or H-Field?
« on: August 05, 2014, 03:58:01 PM »
Everyone uses the term "H-Field" to describe the magnetic field of the lightning.

I thought H-Field involves permeability. Is the magnetic component of the incoming E-M wave actually "B-Field" and becomes an H-Field once it enters the ferrite antenna? (describing the internal field within the antenna)

Is the incoming field from the lightning actually B-Field, and H-Field exists within the antenna?

Inquiring minds want to know....


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Offline JonathanW

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Re: B-Field or H-Field?
« Reply #1 on: August 05, 2014, 04:40:43 PM »
I was wondering when someone would say something about this :)

It's been 10 years since I took a "fundamentals of magnetics" class.  I'll have to go to my notes.

Offline Cutty Sark Sailor

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Re: B-Field or H-Field?
« Reply #2 on: August 05, 2014, 04:43:55 PM »
Have fun: It's sorta like this: The H field strength used to be measured in oersteds.
H represents the "magnetic field strength". B is the density of the flux lines, M is magnetization of any material inside the H field. B is the induction and H is the field generating the induction. M would be the magnetic force induced in the material. H is measured in amperes per meter, B by number of lines per unit of measurement, and M could be joules or amperes per meter.
M would be what exists within the antenna. So given an H-field of a certain strength crossing an inductive material of a certain density/permeability  would create a B field of so many lines, which would induce an M energy of so many joules or amperes.  More or less.

Work it all backwards for a transmitter.  More or less.
Now .... "Leave Brittany Alone!"....
« Last Edit: August 05, 2014, 04:50:03 PM by Cutty Sark Sailor »