(12-13-2021, 07:11 AM)wibble Wrote: It depends on the thermal paste, but I guess they picked one that's suitable for the job. Even thick thermal paste conducts better than an air gap. Similarly the thin steel shield isn't an ideal heat spreader but is better than nothing. I don't know if the shield is there to keep RF out or in, but operating without it probably counts as modification which licensing authorities don't usually like.
To be fair the harmonics it might radiate are in the mW rance and dissipate quickly.
FWIW I have never seen or heard of anyone getting their phone explored by regulators, even most pirate radio is ignored.