I was particularly interested in the aluminium foil option given how convenient it is [0] At the time I also had internet issues, no wired internet available and slow 4G, with only a handful of devices in the household it's easy for a rogue one to consume all the bandwidth (mainly Apple devices which basically do whatever they want).
I actually went ahead and tried different tin foil methods, mainly the "big bundle of aluminium foil" idea, and it worked out pretty well as both an LTE and wifi blocking when I needed to reliably disable an apple device.
I found that neatly folding is a bad idea, it seems to be too difficult to remove the gaps, and so regular structures just make these gaps into effective antenna ports... but if you just go with the layered irregular approach, it seems to work pretty well. My armchair theory is that although it's still not a very well closed structure, there are so many reflections at so many angles with so many compartments of different shapes and sizes that even a broad spectrum signal attempting to propagate along those paths cancels itself out. To be clear, I'm aiming to create the longest path of propagation when wrapping these, so you can't just wrap around one axis and fold the sides, you need to go nuts, wrap all orientations and make it crumply.
The main issue with this approach is speed and poor re-usability, i.e covering and uncovering a device is slow and usually destroys the aluminium foil too much for many uses. Another interesting options to fix the re-usability might be space blankets which unlike aluminium foil do not break so easily.
I was particularly interested in the aluminium foil option given how convenient it is [0] At the time I also had internet issues, no wired internet available and slow 4G, with only a handful of devices in the household it's easy for a rogue one to consume all the bandwidth (mainly Apple devices which basically do whatever they want).
I actually went ahead and tried different tin foil methods, mainly the "big bundle of aluminium foil" idea, and it worked out pretty well as both an LTE and wifi blocking when I needed to reliably disable an apple device.
I found that neatly folding is a bad idea, it seems to be too difficult to remove the gaps, and so regular structures just make these gaps into effective antenna ports... but if you just go with the layered irregular approach, it seems to work pretty well. My armchair theory is that although it's still not a very well closed structure, there are so many reflections at so many angles with so many compartments of different shapes and sizes that even a broad spectrum signal attempting to propagate along those paths cancels itself out. To be clear, I'm aiming to create the longest path of propagation when wrapping these, so you can't just wrap around one axis and fold the sides, you need to go nuts, wrap all orientations and make it crumply.
The main issue with this approach is speed and poor re-usability, i.e covering and uncovering a device is slow and usually destroys the aluminium foil too much for many uses. Another interesting options to fix the re-usability might be space blankets which unlike aluminium foil do not break so easily.
[0] https://news.ycombinator.com/item?id=29415451