My online geiger counter which I described earlier has been offline for some time. During that time I experimented with a standalone Arduino with the goal of making a dedicated board for the setup. I have now completed the board shown in the picture below.

In the picture you can see the HV generator on the top of the board, on the lower left the Arduino standalone parts along with a MAX232 as a level converter for easy serial hookup and on the right two tubes connected in parallel, a SI-29BG (beta and gamma) and a SI-12B for added alpha sensivity. Also shown are the USB>Serial adapter and a separate USB connector to provide 5V to the board. Read more »

With the developing nuclear disaster in Japan, I discovered that there is lots of money being made selling geiger counters. Prices of geiger counters on Ebay and various other places seem to have tripled instantly.

Well, you could say that’s the free market in action. But it wouldn’t surprise me if prices are driven up by people not actually needing geiger counters but buying them anyway out of fear while they are not likely to experience any effects of the disaster.

Today I saw something much worse, some German on Ebay trying to sell a “geiger counter” which actually is a high range survey meter, a CDV715 according to the picture. Read more »

I own a CDV-700 geiger counter of which the tube stopped working. It turns out that replacement tubes are both hard to find and expensive. The simplest option is to buy the LND 720 which basically is a drop-in replacement that should cost about $100.

It’s also possible to use cheaper, easier to find tubes with the CDV-700.  I found the following post from radio amateur K0FF on the “Geiger Counter Enthousiasts”  group on Yahoo groups. It describes a simple circuit to adapt tubes of varying voltage to the CDV-700. I built one, and it works! Read more »

I have always had an above average interest in radioactivity.  It’s a subject with political, sociological and scientific aspects. I have been mostly interested in the scientific part, but I also closely follow any news and other developments. With the earthquake in Japan and the following nuclear disaster the discussion about nuclear energy has  been fired up after being quite silent for years. In the Netherlands there was talk about building a new reactor next to the existing plant in Borssele. Well, I guess it will be a bit harder now to get support for this plan…

To be honest, watching the developments with the damaged reactors in Japan got me thinking again. Is nuclear energy a proper way of generating electricity? Sure,  for the immediate surroundings it is very clean. There are virtually no CO2 emissions and with proper shielding and maintenance you’ll need some pretty advanced equipment to measure any radioactivity coming from a reactor. Still, uranium mining is not very nice for the environment and there is no clear solution for storage of waste. And, if a reactor malfunctions there is the possibility of widespread contamination as currently seen in Japan. So, while I am not against nuclear energy my support for it has weakened somewhat.

Anyway, enough rambling, how to monitor radiation with your computer!

Update 18/4: Guess I am not the only one doing some monitoring: http://radgoes.blogspot.com

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Intro

Hoe moeilijk is het om aan een (zeer) kleine hoeveelheid radioactief materiaal zoals uranium te komen?

Gezien de afstand die het normale volk heeft tot “mysterieuze” zaken als radioactiviteit, redelijk moeilijk zou je denken. De beweging tegen kernwapens en -energie hebben hard hun best gedaan om dit onderwerp zo beladen mogelijk te maken en zijn daar zeker in geslaagd. Read more »