[KK7NIL]

> ferrous shield would warp magnetic flux lines

It wouldn't, the only way to "shield" from magnetic fields is to get them to induce Eddy currents and but that requires more and more length and as the wavelength gets longer and essentially infinite for the Earth's field which is very slow moving.

> RF ground up there. "ground" is relative and not at all required for a Faraday cage to work.

[spwa4]

However that is still vulnerable to the microwaves. The issue is that this setup catches microwaves and while, yes, it prevents the waves from entering the electronics it does so by converting them to heat. So if this cage has caught 100J * volume (say 100W for slightly over 1.5 minutes), the electronics are above 100 degrees, and the solder joints are releasing.

The advantage of microwaves is that unlike lasers, kilowatt strong microwaves are easy to generate, it is an incredibly well studied problem, because that's how early radar systems worked. They are what secured the skies above London against the Nazi air force.

Israel seems to be trying another approach with lasers. They decided it doesn't matter if the laser is powerful, if you just have hundreds of 2W lasers aimed at the same target.