I agree with everyone about the incomplete cancellation of the field of a twin lead, but only at short distances: when you move away from the line, the distances with respect to each wire tends to equalize, with the result that the field of each wire cancels out, because current flows in the opposite direction. That is why twin lead do not radiate significantly.
With a coaxial cable we have more protection but it is not a panacea. I have a coaxial cable that is 2 meters long. When I connect it to the input of my VHF/UHF receiver, all local FM stations are received 10 to 30 dB above the background noise. With another one-metre coaxial, I receive the most powerful. Only with the 1 meter coaxial supplied with my Siglent generator or with a RG214 cable, 6 meter long, the receiver provides only background noise.
We need high quality coaxial cable if we are dealing with W or kW instead of hundreds µW or some mW from the radio, and are expecting to detect induction from a coaxial instead of artifatcs.
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"Open your mind, but not like a trash bin"
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