Strange anomaly detected in my data

[Jan Helebrant]

Hi,

I just uploaded one file from one of our bGeigies:

https://api.safecast.org/en-US/bgeigie_imports/30233

and got warning about possible anomaly.

OK, I noticed sligtly elevated values in one direction but not such a big one.

The API says I have one point with value 0.86 microSv/h and 288 CPM:

However I do not see such value in QGIS displaying the same LOG data:

But says it is about 0.3 microSv/h and about 100 CPM. The raw data also seems to be OK:

$BNRDD,2833,2017-07-30T13:49:53Z,71,6,8632,A,4954.7511,N,01417.9147,E,424.60,A,7,121*4E

$BNRDD,2833,2017-07-30T13:49:58Z,73,8,8640,A,4954.7586,N,01417.8840,E,426.00,A,8,113*47

$BNRDD,2833,2017-07-30T13:50:03Z,75,5,8645,A,4954.7656,N,01417.8819,E,427.50,A,8,113*49

$BNRDD,2833,2017-07-30T13:50:08Z,81,11,8656,A,4954.7746,N,01417.9058,E,428.80,A,9,93*48

$BNRDD,2833,2017-07-30T13:50:13Z,102,24,8680,A,4954.7843,N,01417.9331,E,430.20,A,9,93*70

$BNRDD,2833,2017-07-30T13:50:18Z,108,7,8687,A,4954.7900,N,01417.9528,E,428.30,A,9,93*47

$BNRDD,2833,2017-07-30T13:50:23Z,107,6,8693,A,4954.7950,N,01417.9694,E,426.70,A,9,93*4F

$BNRDD,2833,2017-07-30T13:50:28Z,103,5,8698,A,4954.7954,N,01417.9848,E,425.60,A,8,113*79

$BNRDD,2833,2017-07-30T13:50:33Z,103,8,8706,A,4954.7984,N,01417.9991,E,424.00,A,8,111*75

So what is wrong? Did I miss anything?

thanks

Jan

[Nick Dolezal]

Hey Jan,

This particular warning can be disregarded.  The anomaly detection is firing here based off the CP5s, rather than the CPM.

If you look in your screenshot, the values from the log file for that point are 102 CPM and 24 CP5s.  24 * 12 = 288 CPM.

Both values are used by the bGeigie Log Viewer, with the CP5s being used preferentially at higher count rates.  However, presently only the CPM value will appear in the apps or on the web map.

[Jan Helebrant]

OK,

it looks like we have a faulty bGeigie. I just looked on this one (did not submit it after noticing that values):

https://api.safecast.org/en-US/bgeigie_imports/30378

and in one direction the data are looking normal while on the way back there are values like 4 or even 12 microSv/h.

We will have to ask current user to return this particular device and perform some diagnostics. Did you already experience such kind or malfunction? I was first thinking about some source of electromagnetic interference but the above mentioned is a walking trip. So maybe a cold joint somewhere.

regards

Jan