Written by: Norio Watanabe
Safecast Volunteer from Koriyama
On a cloudy day in early summer, Safecast members and volunteers gathered in Aizu-Wakamatsu to hold a bGeigie Nano-assembling workshop. The workshop took place at the IT company Eyes, JAPAN Co., Ltd. courtesy of the company president Mr. Yamadera.
Through the first round of measurements by car, Safecast mostly completed the radiation map of Fukushima Prefecture in 2011. The map is available on the Safecast.org website. Data has been collected at 10 million points so far and is being updated every day. The radiation map is becoming more detailed as volunteers take measurements while either cycling or walking in order to measure radiation in places that cannot be accessed by car.
The bGeigie Nano is small, light and much easier to use than the original b-Geigie. It has a measuring mode and a recording mode. In measuring mode, you can take the bGeigie Nano out of the case and measure surface contamination. The measurements can be converted from CPM to Bq/m2. In recording mode, CPM measurements are recorded on the microSD card along with the GPS coordinates, the time and the name of the person taking the measurements (the owner’s name is registered in each bGeigie Nano). The data can be shared and shown on the map by uploading it onto the Safecast website.
If you have soldering experience, assembling the bGeigie Nano should be relatively easy (although, with my old eyes, some parts are difficult without a magnifier). It does not require detailed soldering of ICs for example because most of the circuit parts are provided in the form of commercially available add-on boards, called “breakouts.” All you need to do is solder resistors, capacitors, transistors, switches, connectors, and some wires. (If your kit contains any incorrect parts, I recommend that you use the opportunity to visit nearby parts shops or to communicate with a Safecast member or volunteer who has experience in making the bGeigie Nano. Both are fun experiences.)
Assembling the bGeigie Nano takes about an hour if you’re experienced. It may take half a day if you are a beginner and need guidance. The bGeigie Nano is not yet sold as a finished product, and it gives you the opportunity to enjoy learning how it works while assembling it. You will also appreciate that despite its high performance, the price of the kit is low.