--> ap/xxxxx

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Second set of scrying board prototypes from: (pcb#16)

http://pcbcart.com

Working succesfully.

Sidenote: Now resolved on 6min30s for Artoz pastel foggy paper!

USB-interfaced Hardware RNG with avalanche noise transistor: (tech_notes2#33)

Based on designs in white noise workshops and on:

http://www.cryogenius.com/hardware/rng/

and:

http://robseward.com/itp/adv_tech/random_generator/

Schematic:

http://1010.co.uk/images/noise2.pdf

PCB:

http://1010.co.uk/images/noise2-Component.pdf

Code:

[Also as reference for avr-gcc/ATmega8 analogue signal input and serial RX/TX]

http://1010.co.uk/noise_ser1.c

Notes:

Reverse-biasing of a 2n3904 transistor across 20V (produced by MAX232), generates avalanche noise which is amplified by one more transistor and further amplified and transformed into a square wave by Schmitt trigger 74HC14. This signal is sampled as a 1 or 0 by the digital input of an ATmega8. The sample is unbiased after Von Neuman and accumulated towards a single byte which is transmitted to the PC by way of USB/serial interface (FT232RL).

Testing:

Using dieharder from:

http://www.phy.duke.edu/~rgb/General/dieharder.php

cat /dev/ttyUSB1 > testrnd

dieharder -a -f testrnd -g 66