These circuits are really simple. Unless the NSA has backdoored solid-state physics it's no greater a risk than this approach. (The NSA very well could backdoor the camera you point at these pendulums).
Hmm, I had to check this and came across this thread on Reddit. NIST has a standard for it, but the exact point is that _that_ can be influenced by them.
Also, somewhere in the thread, they mention that it is probably too hard to verify how it is actually implemented in the hardware.
Also, somewhere in the thread, they mention that it is probably too hard to verify how it is actually implemented in the hardware.
https://www.reddit.com/r/crypto/comments/klcx4p/is_true_rand...
I guess in security only the paranoid prevails...
Or it is indeed just a cool gimmick...