The HOPE conference was last weekend and [Nathan] spent some time with fellow members of Makers Local 256 developing this badge proximity sensor. They took one of the HOPE badges, which have a radio on board for the tracking network, and wrote code for its MSP430 to detect other badges nearby. It uses a Geiger counter they brought with them as an enclosure, re-purposing the analog gauge to reflect the level of active radio signals in the area. You’ll find their demo clip embedded after the break.
If you managed to get your hands on one of these badges, don’t be shy about sharing your hacks. We want to see them.
Continue reading “HOPE badge proximity sensor”
[Aaron] A.K.A. [A1ronzo] at SparkFun has put together a hackable USB Geiger Counter. In his tutorial, he gets the Geiger counter to work as a random number generator. Later, he analyzes and discusses how well it works as a random number generator. In the past, we have seen a number of radiation detectors hacks such as the Mr. Fission digital Geiger counter, a count accumulator, and a Polonium detecting pen, Besides our inital thoughts of speeding up the number generation, and using it as a special character device, what else can you come up with to do with this device?
[Sebastian Tomczak] was borrowing a homeade muon detector from his friend, and managed to hook it up to his computer through an Arduino. The detector itself uses 3 fluorescent tubes to detect radiation. Three separate tubes are used in order to filter out terrestrial radiation; cosmic radiation will fall in-line with the tubes and pass through at least two of them, whereas terrestrial radiation will only hit one. There is some basic circuitry to amplify the signal and then perform the OR operation.
[Tomczak] used an Arduino to take the raw data and feed it into his computer. He then used Max/MSP to analyze the data and filter out background noise, leaving only the cosmic ray data. He didn’t mention what he was going to use the data for, though. Maybe he’ll hook it up to a synthesizer.
Related: Digital Geiger counter
Worried about radiation levels? I’m not, but I still want to build one of these. Mr. Fission here was built by the same guy that’s behind the OpenTracker project. [Scott] based it on the Bargraph Geiger counter built by [Russel E. Cliff]. Both use a standard Geiger tube like the LND712. The tube works with high voltages – easy enough with older electronics, but it’s a slightly tougher challenge with todays low voltage gear. [Scott] used the high voltage power supply from the original project, and built the rest around a good ol’ Motorola HC86 series processor. [Scott]’s idea of using an inverter supply designed for a cold cathode lamp is definitely an interesting one.