Geiger Counter Gammascout

gammascout +heavy metal (Cd) in pelicase for underwater open Gammascout, rear side view


The Gammascout Geiger Counter is a calibrated measurement instrument for alpha, beta and gamma rays.
The central processor is a MSP430.
The USB version uses a FT232BM for the conversion USB to UART for the MSP430.
The hardware is good, but the software is awful: For a plot of the measured and read values (dose rate/count) you first have to use the Calculate-button and than you find a button for show; the Display-Button shows only a log. The program can't be terminated via Alt-F4, on my Notebook with a CoreDuo T2050 (1,6 GHZ, 1 GB RAM, MS-WinXP) it needs 1 minute to start (every Quake game starts much faster) and sometimes the mouse pointer is invisible in the program window. And the program can use one the first (virtual) ten serial ports which are often already used by a bluetooth driver.


Some measurement results

Indoor dose rate in Germany, Nuremberg (300 m AMSL): 185 ± 10 nSv/h
Outdoor Dose rate in Germany, Nuremberg, 4.5 m underwater (swimming pool):

About 90 nSv/h

Indoor Dose rate in Germany, Nuremberg, 30 cm underwater:

160 ± 10 nSv/h

Indoor dose rate in Germany, Mülheim (100 m AMSL): 230 ± 10 nSv/h
Indoor dose rate in Germany, Bremervörde (4 m AMSL): 170 ± 10 nSv/h
Indoor dose rate in Hongkong (10 m AMSL): 400 ± 50 nSv/h
Indoor dose rate in Taipei (100 m AMSL): 195 ± 20 nSv/h
Indoor dose rate in Tanzania, Dar es Salaam (10 m AMSL): 130 ± 10 nSv/h
Indoor dose rate in Tanzania, Moshi (900 m AMSL): 280 ± 10 nSv/h
Dose rate from 15 g potash directly under the gammascout and 200 g salt with 50 g K above:

25 ± 10 nSv/h (total dose rate: 210 nSv/h)

Dose rate from 200 g potash directly under and above the gammascout :

100 ± 10 nSv/h (total dose rate: 285 nSv/h)

Dose rate from 1 kg potash directly around the gammascout :

220 ± 10 nSv/h

Dose rate close to 90 g UO2(NO3)2.6H2O:

About 25 µSv/h

Dose rate from a 49 kdpm 14C standard capsule, placed on the window of the counting tube:

About 26 µSv/h

Dose rate close to 50 g ThO2:

About 120 µSv/h

Comments:
If not marked with about the value is an average of minimum two 24 hour averages, measured 2006 or later.
The comic ray intensity is anti-correlated with the sunspot activity and has therefore a period of 11 years, with a variation of 12 % around the average value (Physik Journal, March 2007, p. 60).
Measurements of the cosmic ray variations can be found here:
http://www.durangobill.com/SwindlePics/SwindleCosmicRays.gif
http://www.brighton73.freeserve.co.uk/gw/solar/cosmic_rays.gif
http://science.nasa.gov/headlines/y2005/images/afraid/doserates.jpg
and in the cosmic ray variations sites chapter at
http://helios.izmiran.rssi.ru/cosray/main.htm#links


Trip from Nuremberg to the highest summit of the Mount Kilimanjaro and back

gammascout on the kibo summit


Uhuru peak at 2008-07-14 (winter), at sunrise (6 am), Dose rate: 0.7 µSv/h, Wind: 8 m/s, 7.4°C, 495 hPa.

Plot of the dose rate
Short description
Data file
Raw data
Machame route profile

Outdoor measurement results i found in the web

Dose rate in Chernobyl 2006, source http://www.pripyat.com/de/news/journal/2007/03/21/1596.html :

30 µSv/h

Dose rate at the beach of Lake Karachay 2007, source http://de.wikipedia.org/wiki/Karatschai-See :

71.5 Sv/h

Comments:
At the beach of Lake Karachay you get a deadly dose in about ten minutes!
If you stay at this beach till you die, you need only about one hour to die!

Links