Project RNG: Radiation-Based Random Number Generator Team Oregon Chub Colton Hamm (Team Leader) Alex Brotherston Ashley Donahoo Matt Johnson Advisor: Dr. Hoffbeck, Dr. VanDeGrift, Dr. Osterberg Industry Representative: Mr. John Haner Bonneville Power Administration University of Portland School of Engineering

Introduction Our project generates random numbers from radioactivity Building a radiation sensor, designing a MOSIS chip and using 7-segment displays University of Portland School of Engineering

Scorecard Completed Final Report v0.9 Interfaced Geiger tube with CPLD University of Portland School of Engineering

Additional Accomplishments Gathered over 3700 bits of data to be analyzed for statistical tests. Replaced function generator with batteries to power device. 3 batteries University of Portland School of Engineering

Plans Conduct statistical tests Complete Final Report v.95 Add reset and hold buttons to device Work on Founder’s Day presentation University of Portland School of Engineering

Milestones Status Description Original Target Previous Present Completed Construct and test the prototype voltage multiplier. 14 Feb 11 11 Feb 11 Construct final voltage multiplier 21 Feb 11 20 Feb 11  Interface pulse generator, transformer, voltage multiplier, and Geiger tube 14 Mar 11 22 Feb 11 Missed Final Report v0.9 13 Mar 11 25 Mar 11 Interface Geiger tube and CPLD 30 Mar 11 21 Mar 11 Interface all aspects of device 29 Mar 11 On Track Final Report v0.95 1 Apr 11 Final Report v1.0 8 Apr 11 Founder’s Day Presentation Complete 12 Apr 11 Toward the end of this file are two slides titled “Understanding Milestone Dates” and “Color Coding Milestones” respectively. Review these carefully before completing this slide. University of Portland School of Engineering

Concerns/Issues Concerns regarding battery power, especially with the large display for Founder’s Day. Concerned about statistical tests proving that our numbers are truly random. Concerns that case may not be done by Founder’s Day and shielding issues. University of Portland School of Engineering

Conclusions The Geiger tube, CPLD, and display have all been interfaced and are working. Statistical tests will show if numbers are truly random. University of Portland School of Engineering

Questions? University of Portland School of Engineering

Secret Geiger Tube Slides Model: Geiger Tube as a Switch Switch=open, V=500v Switch Closes, V= 500v*10M/(1M+10M)=455v The capacitor blocks DC, so the signal starts at 0 volts, and falls by 45 volts when the switch closes V University of Portland School of Engineering

A Geiger–Müller tube consists of a tube filled with a low-pressure inert gas, such as neon, and an organic vapor or a halogen gas. The tube contains electrodes, between which there is a potential difference of several hundred volts, but no current flowing. The walls of the tube are either entirely metal or have their inside surface coated with a conductor to form the cathode while the anode is a wire passing up the center of the tube. When ionizing radiation passes through the tube, some of the gas molecules are ionized, creating positively charged ions, and electrons. The strong electric field created by the tube's electrodes accelerates the ions towards the cathode and the electrons towards the anode. The ion pairs gain sufficient energy to ionize further gas molecules through collisions on the way, creating an avalanche of charged particles. This results in a short, intense pulse of current which passes (or cascades) from the negative electrode to the positive electrode and is measured or counted. -Wikipedia 0v -40v University of Portland School of Engineering