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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.