Radio or wi-fi signals inherently different from electromagnetism?

radio and wifi signals are defined by the parts of the EM spectrum they use. I don't think there's anything except wavelength that specifically differentiates them from any other kind of EM activity.

Electromagnetic waves very only in there wavelength, so sunlight, ultraviolet, microwave, radio waves all have a different wavelength. It is possible to stand beneath a high tension power cable and light a handheld fluorescent tube from the waves coming from the cable. most animals have sensors that can detect different frequencies It is said Dolphins can see using sound waves and some snakes can see heat using their tongues. So your alien problem would be perfectly feasible but difficult to solve.

Mind you, different wavelengths of RF do have different effects. Microwaves work because the RF frequency is specifically selected to excite water molecules. Color receptors in the eye are designed to pick up particular wavelengths of light. X-rays work because biological tissue is transparent to them. Shortwave is useful because it reflects off the ionosphere and therefore defeats line-of-sight limitations.

One of the aspects of RF detection is that the detector has to be larger than a half-wavelength, IIRC. So human-sized beings would be less likely to detect 60 hz, for instance, than wifi.

Fiender said:

My question is, does it make technical sense that these humans would be able to utilize electricity? Is there something inherently different with the waves/energy given off by, say, an active radio tower or a modern phone, and those given off by an in-use battery or power line?

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They would have to have a DC-based electricity grid rather than AC as we have.

https://engineering.mit.edu/engage/ask-an-engineer/whats-the-difference-between-ac-and-dc/

-cb

This may be of interest as well regarding radio waves, and the different allocations:

https://upload.wikimedia.org/wikipe...locations_Chart_2016_-_The_Radio_Spectrum.pdf

cbenoi1 said:

They would have to have a DC-based electricity grid rather than AC as we have.

https://engineering.mit.edu/engage/ask-an-engineer/whats-the-difference-between-ac-and-dc/

-cb

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Note that long distance high voltage transmission lines tend to be DC. This is done to avoid inductive losses.

Your wifi, cell phone and other things built to be radios should give a far more powerful signal than things not designed specificly to do that and could be shielded. See Faraday Cage for shielding.

Fiender said:

My question is, does it make technical sense that these humans would be able to utilize electricity? Is there something inherently different with the waves/energy given off by, say, an active radio tower or a modern phone, and those given off by an in-use battery or power line?

Click to expand...

One chief difference is that power lines are meant to move energy around from A to B while a radio antenna is meant to broadcast a signal as far as it can go.

If you point a flashlight at something, the light is going in one direction. Someone standing to the side or behind you generally isn't going to get splashed by the light. However, if you light up a flare (or take the head off a maglite) you now have a light blasting out in all directions. Folks are definitely going to notice that. By analogy, a radio antenna is like that flare or big ball of light.

What's neat is that you can direct these radio waves around - use a directional antenna with a super tight beam. It won't be as easy to pick up the signal, but it won't be blasting its noisy self all over the place. That might be a workaround for how folks communicate without annoying their alien neighbors.