However I don't think you'd be able to easily manipulate the random stream.
By triggering the random tube you just generate a random number, but even by triggering it continuously you cannot directly manipulate the bytes. The counter is not reset after every event.
Moreover: the timer/counter is clocked at 20M, for a 16 bit timer it overflows every 3ms. The tube is inhibited for a similar amount of time by a monostable 555. And this inhibit time is controlled by an RC network that is separated from the timer/counter crystal. So even noise and fluctuation on this two clock sources generate some randomness.
I'm not saying that it is impossible to manipulate, I'm saying congrats if you figure out a way.
A Geiger-Müller tube has a dead-time after a detection event where it won't register a new event. Thus it's possible to saturate the tube. This would drastically reduce the entropy it generates, from what I can gather.
I should try and see. The inhibit from the monostable timer could somewhat "transfer" the randomness source from the geiger to the time constant of the 555
However I don't think you'd be able to easily manipulate the random stream.
By triggering the random tube you just generate a random number, but even by triggering it continuously you cannot directly manipulate the bytes. The counter is not reset after every event.
Moreover: the timer/counter is clocked at 20M, for a 16 bit timer it overflows every 3ms. The tube is inhibited for a similar amount of time by a monostable 555. And this inhibit time is controlled by an RC network that is separated from the timer/counter crystal. So even noise and fluctuation on this two clock sources generate some randomness.
I'm not saying that it is impossible to manipulate, I'm saying congrats if you figure out a way.