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Using monopole antennae is simple and convenient for practical use, but they introduce unwanted complexities which are against the purpose of the experiments. After searching for a while I finally found this source which I think is the best solution for the problem. http://vk5ajl.com/projects/baluns.php#current QuoteCORE TYPE CURRENT BALUNHighly recommended. This is a very low loss balun and ideal for use with a tuner.This balun works by controlling currents. THERE IS NO TRANSFORMER ACTION. The two windings must be in the same sense (dots at the same end). The magnetic fields of opposing balanced working currents will cancel each other out and so present very little impedance (other than the resistance of the wires) to these currents. On the other hand, common mode currents will produce a mutually inductive magnetic field and face a high impedance.This means the more turns the better, up to a point. In this case, the windings are a transmission line that has losses but these are much lower than the losses transfering energy from one winding to another through a core.Design considerations are really very minimal. Since the losses of balanced lines are low compared to coax, you aren't losing much except for the resistance of the wires which is very low compared to radiating resistance anyway.The current balun shown here, wound around a steel bolt, is probably a little crude but why not? Steel or iron is not normally used for RF because there are too many eddys making it too inefficient for transformers. In this application, since there is no magnetic effect for the desired currents, it doesn't matter. For common mode currents on the other hand, inefficiency is an advantage. Not only is a high impedance presented to common mode currents, the energy from them is absorbed by the bolt.I'd like to hear if someone here has a second opinion.
CORE TYPE CURRENT BALUNHighly recommended. This is a very low loss balun and ideal for use with a tuner.This balun works by controlling currents. THERE IS NO TRANSFORMER ACTION. The two windings must be in the same sense (dots at the same end). The magnetic fields of opposing balanced working currents will cancel each other out and so present very little impedance (other than the resistance of the wires) to these currents. On the other hand, common mode currents will produce a mutually inductive magnetic field and face a high impedance.This means the more turns the better, up to a point. In this case, the windings are a transmission line that has losses but these are much lower than the losses transfering energy from one winding to another through a core.Design considerations are really very minimal. Since the losses of balanced lines are low compared to coax, you aren't losing much except for the resistance of the wires which is very low compared to radiating resistance anyway.The current balun shown here, wound around a steel bolt, is probably a little crude but why not? Steel or iron is not normally used for RF because there are too many eddys making it too inefficient for transformers. In this application, since there is no magnetic effect for the desired currents, it doesn't matter. For common mode currents on the other hand, inefficiency is an advantage. Not only is a high impedance presented to common mode currents, the energy from them is absorbed by the bolt.
Did you wrap the power supply / battery in aluminium?
The outcomes of your experiments will be in accordance with Maxwell's equations.What are the experiments/ videos for?
How else would you get those information?
Quote from: hamdani yusuf on 20/04/2022 07:25:24How else would you get those information?Look at all the experiments that have been done in the past.
“It's impossible for a man to learn what he thinks he already knows.”― Epictetus
I've recorded some videos experimenting on radio wave using dipole antenna. I think it will give us access to explore further on polarization, wave direction by phase shifting, and some other phenomena which are harder to demonstrate using spring antenna.
Why don't Submarines use Radio or GPS?
As BC has already pointed out radio waves behave exactly as Maxwell's equations predict, no more, no less. Any experiment one can think of will already have been done, countless times. Radio is one particular of physics that has received a colossal amount of experimentation.
True, but I think the outcome will be consistent with Maxwell's eqns.
Maxwell's equations predict, no more, no less.
This assertion is where my concern lies.
The Faraday paradox or Faraday's paradox is any experiment in which Michael Faraday's law of electromagnetic induction appears to predict an incorrect result. The paradoxes fall into two classes:Faraday's law appears to predict that there will be zero electromotive force (EMF) but there is a non-zero EMF.Faraday's law appears to predict that there will be a non-zero EMF but there is zero EMF.Faraday deduced his law of induction in 1831, after inventing the first electromagnetic generator or dynamo, but was never satisfied with his own explanation of the paradox.
It is tempting to generalize Faraday's law to state: If ∂Σ is any arbitrary closed loop in space whatsoever, then the total time derivative of magnetic flux through Σ equals the emf around ∂Σ. This statement, however, is not always true and the reason is not just from the obvious reason that emf is undefined in empty space when no conductor is present. As noted in the previous section, Faraday's law is not guaranteed to work unless the velocity of the abstract curve ∂Σ matches the actual velocity of the material conducting the electricity.[30] The two examples illustrated below show that one often obtains incorrect results when the motion of ∂Σ is divorced from the motion of the material.