Using an RF signal to determine the material of an object

I see, thank you for your insight. I will definitely have to factor that in as well and start thinking of the concept in the same way.

Could it be possible to hard code that a certain range of attentuation of the signal would be a certain material?

Thank you for your reply!

That video just shows simple data connection between two modules, it has absolutely nothing to do with what you are trying to do.

You can’t just put something in the way between the transmitter and the receiver. These are radio waves they will bounce all over the place. You need an radio dead anechoic chamber to remove them. Any object less than the wavelength of the radio signal will not block the radio signal it will simply go round it. So in this case 433MHz is about two 70cm, so to make sure the radio wave goes through an object at these frequencies you will have to have the object at least a meter in both dimensions.

You simply will not get any results with what you are trying.

No, physics does not work like that, especially at those sorts of frequencies.

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I see...after reading more of what the others have sent and researching more, is it possible then to measure the strength of the signal in any way at the receiver antenna using an Arduino board and a receiver module?

Thank you for your reply!

Not with those modules. They have either a huge gain with limiting, or an active ALC (automatic level control). The strength of the signal is lost in those. Even if not, achieving the directionality that you would need to detect an obstacle between transmitter and receiver, is beyond the simplicity of what you have in mind.

In short, it's a dead duck. :grin:

Not going to happen.

Or you can use a metal detector, the regular ones are not reliable, but mine, which I built a long time ago, was tuned to a specific metal with 100% reliability.

You can, but the strength will depends to the thickness of material, you need to measure the phase of reflected signal ......