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 ID 1:EB072480 Waterford, MI 
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Joined: Wed May 01, 2013 7:18 pm
Posts: 55
Location: Waterford, MI.
http://netc.com/chart/view.php?n=1%3AEB072480 --CHART MEMBERS ONLY--

All,
Please ignore alerts for station 22 ID 1:EB072480 in Waterford, MI.

This morning my GMC-200 fell off my window sill and the case cover flew off. I didn’t have time to replace the cover before I left for work so just placed it back on the sill and then noticed the high counts and red icon on the map once I got to work.

So the counts are now higher than my sites NORM so it will be alerting until I get back home and replace the cover this evening.

This brings up a good question; should I leave the cover off or drill some holes in it to increase the sensitivity? I was surprised how much higher the readings got with just the cover off. Went from average CPM of about 14 up to 36 or so in just an hour.

Harlan, is there a way to reset my sites data if I do decide to leave the cover off, or at least place a note to show why the readings increased all of a sudden?

-Randy

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Station ID 1:EB072480 Waterford, MI, US
http://netc.com/chart/view.php?n=1%3AEB072480
Prepare, plan, stay informed and safe!


Thu Aug 22, 2013 7:41 am
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Joined: Mon Jan 28, 2013 6:51 pm
Posts: 746
Location: Arkansas
The cover does not make any different that would be detected by the geiger counter. It may be the electronic, tube that may get out of calibration. Turn of the power on the PI and GC and let it sit for 30 minutes. Then plug it in and lets see what the charts will read. Sorry you dropped it, some of the more expensive GC would not work if they were dropped.
harlan


Thu Aug 22, 2013 3:52 pm
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Joined: Wed May 01, 2013 7:18 pm
Posts: 55
Location: Waterford, MI.
ok i just got home and will give that a try. Interesting that it didn't seem to have a hard fall as it was hanging rom the power cord when i fond it. The cat must have knocked it over and it just knocked the top cover off. This is the GMC-200 and the cover just easily pops off, no screws required.

Now what scares me is that the spike occurred just as I was replacing it on the window sill, in the same spot is has been for the past 3 months and if you look at the graph it slowly returned to almost normal levels.

Could this be a real reading or has the detector been compromised?

I will post back once I power it off and replace the top cover.

-Randy

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Station ID 1:EB072480 Waterford, MI, US
http://netc.com/chart/view.php?n=1%3AEB072480
Prepare, plan, stay informed and safe!


Thu Aug 22, 2013 8:22 pm
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Joined: Wed May 01, 2013 7:18 pm
Posts: 55
Location: Waterford, MI.
ok i powered down for 30 and my site came back up at 10am EST with the cover back on.

I will let it run like this through tomorrow and if the numbers dont spike again I will take the cover back off and see what happens on Saturday.

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Station ID 1:EB072480 Waterford, MI, US
http://netc.com/chart/view.php?n=1%3AEB072480
Prepare, plan, stay informed and safe!


Thu Aug 22, 2013 9:15 pm
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Joined: Mon Jan 28, 2013 7:40 pm
Posts: 2879
Location: Illinois
I believe your readings were correct. You had such a slow climb and fall, it looks real. The storm that came through Illinois today caused all my equipment to show a rise too. Radiation levels often go up in front of the storm and I believe that happened to you today.

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MY OUTSIDE RADIATION MONITORING STATION:
South Beloit, Illinois - GMC200 Outside on HEPA air purifier, ground level, facing West.
http://netc.com/chart/view.php?n=1%3AEB5A139C


Thu Aug 22, 2013 10:40 pm
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Joined: Wed May 01, 2013 7:18 pm
Posts: 55
Location: Waterford, MI.
Well readings returned back to normal compaired to yesterday morning so you are probbly right. Scary as it didnt even rain at my house yesterday, all the storms were well south of Detroit so thats more then 40 miles south of me.

I will still pull the cover off tomorrow just to be sure this was not a coincidence. When the detector fell it was dangeling by the power and audio cord against the wall and when i placed is back on the sill the window was open and the reading began to slowly climb right away.

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Station ID 1:EB072480 Waterford, MI, US
http://netc.com/chart/view.php?n=1%3AEB072480
Prepare, plan, stay informed and safe!


Fri Aug 23, 2013 7:48 am
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Joined: Mon Jan 28, 2013 6:51 pm
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Location: Arkansas
Dust kills the tube, at least cover it with some paper.


Fri Aug 23, 2013 8:00 am
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Joined: Wed May 01, 2013 7:18 pm
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Location: Waterford, MI.
ok i will only keep the cover off for an hour or so tomorrow morning and will cover the tube with a piece pf paper so see if the readings go up.

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Station ID 1:EB072480 Waterford, MI, US
http://netc.com/chart/view.php?n=1%3AEB072480
Prepare, plan, stay informed and safe!


Fri Aug 23, 2013 9:45 am
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rdesrosi wrote:
Well readings returned back to normal compaired to yesterday morning so you are probbly right. Scary as it didnt even rain at my house yesterday, all the storms were well south of Detroit so thats more then 40 miles south of me.

I will still pull the cover off tomorrow just to be sure this was not a coincidence. When the detector fell it was dangeling by the power and audio cord against the wall and when i placed is back on the sill the window was open and the reading began to slowly climb right away.


Was the sun hitting the tube through the window? I recall hearing that light will cause a change in readings. If you cover it with paper, try black paper to limit the amount of light that gets through.

I am sure the storm had something to do with your rise in readings, but you did get past 60 CPM which when compared to a pancake unit like what I own would be well over 60 CPM. My inside pancake unit did reach a high of 60 CPM but on your unit, you would not reach 60 CPM with the same amount of radiation. If we assume you received the same as me... some other factor might be at play here. Although any air leaks from your window hitting the geiger counter would have allowed the beta radiation to cause a climb higher than my inside units were exposed to. I did verify yesterday during the storm a rise in beta radiation by testing readings inside and outside my car.

I did recently take off the cover of my GMC-200 running on Radiation Network. I then put the geiger counter inside a thin plastic ziplock bag, but my unit does not get direct sunlight. So far I have not noticed any changes but I will compare over time to the readings I get off my Polimaster with what readings I had during the recent storm.

_________________
MY OUTSIDE RADIATION MONITORING STATION:
South Beloit, Illinois - GMC200 Outside on HEPA air purifier, ground level, facing West.
http://netc.com/chart/view.php?n=1%3AEB5A139C


Fri Aug 23, 2013 12:12 pm
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Joined: Wed May 01, 2013 7:18 pm
Posts: 55
Location: Waterford, MI.
The window was open, as is normal when I am not expecting rain but I dont beleive that the sun would have been able to shine directly on the tube, i will confirm tomorrow. The open window seems to confirm what you noticed with an increase in beta. The storm was way south of me but the window also faces south as well.

i will open the cover again in the morning but keep the tube covered with some dark paper to see if there was an increase.

Thanks for all the replies, i am learning about rad monitoring every day..

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Station ID 1:EB072480 Waterford, MI, US
http://netc.com/chart/view.php?n=1%3AEB072480
Prepare, plan, stay informed and safe!


Fri Aug 23, 2013 8:21 pm
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