Here&#x27;s a very old (1997) examination of 3 devices: <a href="http:&#x2F;&#x2F;www.robertnz.net&#x2F;true_rng.html" rel="nofollow">http:&#x2F;&#x2F;www.robertnz.net&#x2F;true_rng.html</a><p>I see a few hardware RNGs, and they&#x27;re usually uncased.  I think I&#x27;d want it in a good quality shielded case.