Separately Detect Electric and Magnetic Field Remotely?
Separately Detect Electric and Magnetic Field Remotely?
(OP)
How can I separately detect electric and magnetic field remotely?
I am aware of the Faraday Effect, but because the magnetic field is so weak I won’t be able to detect the polarization change.
I am aware of the Faraday Effect, but because the magnetic field is so weak I won’t be able to detect the polarization change.





RE: Separately Detect Electric and Magnetic Field Remotely?
DC?
AC? Frequency? Frequency range?
What are you trying to attempt?
What polarization change? H/V, RHCP/LHCP?
What do you mean remotely? How far away?
RE: Separately Detect Electric and Magnetic Field Remotely?
I am trying to attempt is to SEPARATELY detect and measure the electric and magnetic field remotely. At a distance up to 5 miles or more.
RE: Separately Detect Electric and Magnetic Field Remotely?
TTFN
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RE: Separately Detect Electric and Magnetic Field Remotely?
The impedance of free space (Wiki) is the hard and fast relationship of electric and magnetic fields (provided that you're measuring in the far field). Measuring them "separately" is essentially a flawed requirement (unless I'm misunderstanding you). Measure the RF field strength and the E/H fields can be calculated on the back of an envelope.
Top post mentioned the difficulty of detecting polarization changes. Invalid. Detecting the polarization is almost as easy as detecting the signal. Although detecting CP would be another experiment.
As stated by IRstuff, to cover five miles you'll need a proper medium power transmitter (not normally permitted in these typically unlicensed bands), or dedicated and ambitious experimenters with high gain antennas.
RE: Separately Detect Electric and Magnetic Field Remotely?
RE: Separately Detect Electric and Magnetic Field Remotely?
RE: Separately Detect Electric and Magnetic Field Remotely?
If telluric currents could muster enough Faraday effect to be even hypothetically detectable, then the Earth's baseline magnetic field would have humanity's RF signals spinning like windmills. We would have noticed that.
RE: Separately Detect Electric and Magnetic Field Remotely?
TTFN
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RE: Separately Detect Electric and Magnetic Field Remotely?
RE: Separately Detect Electric and Magnetic Field Remotely?
Commercial magnetometers are able to measure variations in the Earth's magnetic field from low-Earth orbits.
TTFN
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RE: Separately Detect Electric and Magnetic Field Remotely?
Red signal is the ISM RF signal (902-928 MHz, or 2.4-2.5 GHz), V is the Verdet constant for the material, B is the delta magnetic signature (at about 100 ppm of the baseline), and the polarization rotation angle ß (basically zero point zero zero zero zero zero zero zero...).