For my money, a triple burrito wrap of foil and ziploc gives 90+ dB attenuation plus moisture and mechanical protection.
Also nitpick, but the E1 pulse doesn't fry beefy transformers, instead it's the long-period E3 pulse (seconds to minutes) that raises the grid voltage and overvolts the transformers.
Technically I'm measuring in the "wrong direction" since I would be very surprised if an EMP were initiated inside a trash can in my basement, but shielding works the same in both directions so this doesn't matter.
It really doesn't, with 1.5GHz you're still in near field regime inside the can.
I did a much lower fidelity experiment this past week with one of my kids.
I have some radios I threw in metal boxes on the off chance something like this happened so we’d have some way to get emergency alerts. To check how well it shielded we threw my phone in it and they called to see if it rang. It did.
So we tried some other things - the microwave (worked), a tool chest (didn’t), a faraday bag (worked), miscellaneous storage boxes (didn’t).
Fortunately, the box with the radio was an old box and some paint had worn from the edges. We made a “seal” out of aluminum foil and tried again. It worked.
This only tested high frequency signals and probably doesn’t reflect real EMP risk in any way, but it was fun to do.
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.
https://www.youtube.com/watch?v=aMct99DiZak
For my money, a triple burrito wrap of foil and ziploc gives 90+ dB attenuation plus moisture and mechanical protection.
Also nitpick, but the E1 pulse doesn't fry beefy transformers, instead it's the long-period E3 pulse (seconds to minutes) that raises the grid voltage and overvolts the transformers.
It really doesn't, with 1.5GHz you're still in near field regime inside the can.
I have some radios I threw in metal boxes on the off chance something like this happened so we’d have some way to get emergency alerts. To check how well it shielded we threw my phone in it and they called to see if it rang. It did.
So we tried some other things - the microwave (worked), a tool chest (didn’t), a faraday bag (worked), miscellaneous storage boxes (didn’t).
Fortunately, the box with the radio was an old box and some paint had worn from the edges. We made a “seal” out of aluminum foil and tried again. It worked.
This only tested high frequency signals and probably doesn’t reflect real EMP risk in any way, but it was fun to do.
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.