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to be honoust: I never understood radiowaves; how I can receive radio in my house? Transferring a complete video through air from laptop to router? Never a clue.

So with that (lack of) knowledge my question: I am sending data with a little sending device which runs at 433,92 MHz (something like this http://nl.aliexpress.com/item/wholesale-Free-Shipping-1pcs-lot-315MHz-433-92MHz-Wireless-Remote-Control-Transmitter-Board-Module-TDL-9912/359001088.html). (it's attached to my raspberry pi)

Now I want to finalize the project, so I thought to wrap it up in a nice plastic box (the led lights will be popping out of the plastic box, but as I don't think the sending device is pretty, it will be INside the box). And now the question: will the signal be influenced?

I guess it probably is in some way, but are we speaking in the terms of 1 or 2 percent, or does plastic (like a drink cup plastic) always take 50% of the signal or....

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As long as the plastic is non-conductive — e.g., not filled or coated with anything containing carbon or metal — you should be fine.

The plastic functions as a dielectric, which passes electromagnetic fields with minimal loss, similar to how a piece of glass passes light.

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  • \$\begingroup\$ Thanks, especially the compare with glass makes sense to me. \$\endgroup\$
    – Michel
    Commented Mar 27, 2013 at 20:25
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I read a great tip for this. Put your case in the microwave. If it gets hot, it is probably absorbing microwaves and will absorb various other similar radio waves.

Use this method at your own risk.

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  • \$\begingroup\$ I remember this method being used to test usability of plastic covering for WiFi cantennas. \$\endgroup\$
    – AndrejaKo
    Commented Aug 24, 2013 at 12:33
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    \$\begingroup\$ If you try this, also put a cup of water with it in the microwave, both to protect the microwave's magnetron and to limit the rate of heating if the plastic is going to heat. Assuming, of course, that you merely want to know if the plastic will heat, as opposed to witnessing its destruction. :) \$\endgroup\$
    – JRobert
    Commented Aug 25, 2013 at 0:23

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