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by BSVogler 36 days ago
I once read that noise of camera in total darkness is apparently a good source.
3 comments

You can already have a good entropy source from a single resistor.

https://en.wikipedia.org/wiki/Johnson%E2%80%93Nyquist_noise

This is what gets me - entropy is hard, but not that hard. I get it goes against everything a computer is built to do, but so does telling time.
Would a CRT TV tuned to channel 3 and no RF input be a good source?
I imagine that there might still be a way to swing by with RF equipment and tip the scales in your favor. And if you're important enough, I'm sure there'll be someone motivatd enough to do this. After all, Polymarket was motivating enough for someone to take a hair dryer to a weather station...

https://www.theguardian.com/world/2026/apr/23/hairdryer-or-l...

In the sense that RF noise can be a source of entropy: Sorta*. But one doesn't need the whole thrift-store television set to do that; the visual aspect of a CRT displaying analog video snow just adds style points**.

*: Sorta, because if someone discovers that the entropy is derived from an analog TV tuned to channel 3, then they also know how to influence it from outside.

**: Style points can have value; it's OK to have fun with work. But that's a secondary function.

better to just switch to... random channel every while :) Not perfect but something.
The noise probably makes the lava lamp wall just as effective as pointing the camera at the Mona Lisa - the lamps themselves are not that unpredictable frame-to-frame.
For the record, the lamps and camera are present in their lobby afaik, so you can actually go there, stand in front of them, and slightly affect the entropy.

A cool parlor trick, certainly.