Since you already suspect that any EMP will come from above why didn't this guy simply turn the trash can upside down and place it over the test setup?

There would be no need to seal anything since the can has a continuous rolled seam. Just use a standard trash can instead of one of those kitchen trash cans that likely has a plastic bottom for easy clean-up.

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lostlogin 3 hours ago | parent | next [-]

That wouldn’t help I don’t think. I’ve had very small holes in a faraday cage results in rf leaks - slots thinner than a credit card.

	▲	doodlebugging 3 hours ago \| parent [-]
		I see what you are saying and understand that problem but I was picturing something like this type of can from Home Depot: https://www.homedepot.com/p/Behrens-31-Gal-Galvanized-Steel-... I use these as planters for my orchard fruit and nut trees. They have no open holes. I have to drill the bottoms or side to add drainage so that the trees don't drown.

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beezle 3 hours ago | parent | prev [-]

Presumes the floor (or other surface) is perfectly flat, perhaps not the best assumption?

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toast0 2 hours ago | parent | next [-]

And that the floor will attenuate any reflected EMP/signal from underneath (should be small in a basement, but ...)

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doodlebugging 2 hours ago | parent | prev [-]

In a reply to another comment I gave a link to the type of trash can that I was thinking about for the cage.

While there may be imperfections in flatness on standard, uncarpeted floors that can allow RF signal to find a path inside (reflections from below or from other angles as another comment mentions) or you could live in a house like mine where flat had a non-standard definition with lots of slop, I believe that you solve those issues by setting the lid upside down on the floor, placing your apparatus inside the lid, then covering and sealing it with the inverted trash can.

You should have plenty of signal attenuation either way.

	▲	toast0 36 minutes ago \| parent [-]
		Trash can lids are usually not so flat, which makes the whole thing wobbly. The ones you linked lack a handle on top, but it's a common feature on metal cans.