| T O P I C R E V I E W |
| Petrovski |
Posted - 05/27/2016 : 13:17:37
Tube power was set to 60kV and 50mA. Energy of the K-alpha is around 18 keV. Source was about one meter away from the 320+. I noticed that the radiation was detected instantly after opening the tube shutter, and stabilized around 5000 CPM after 30 seconds. It took the 320+ a while (over a minute) to cool down and detection levels returned to background.
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Sorry no intensity graph, forgot to set the logger function to take a sample every second. |
| 8 L A T E S T R E P L I E S (Newest First) |
| Petrovski |
Posted - 06/07/2016 : 10:58:59
First I'll try the experiment again with new firmware. I've sent an email to GQ customer support. |
| Distelzombie |
Posted - 06/06/2016 : 12:33:38
Try to build a faraday cage. I once made one that worked great using a sieve and some cardboard with aluminum foil around. |
| Petrovski |
Posted - 06/02/2016 : 11:11:04
@ Distelzombie: you mean like EMC interference? Could be, but since it's in an radiation tight enclosure I'm pretty sure it's just X-rays and the GMC itself in there.
@ ZLM: I have revision 4.12. |
| ZLM |
Posted - 06/01/2016 : 23:46:40
Petrovski: What is your GMC-320 firmware version? The latest version should take care the task priority between counting ,data logging and display task. The counting task always be a highest priority task. |
| Distelzombie |
Posted - 06/01/2016 : 12:50:58
Could it be affected by some electromagnetic radiation? (it can be, I tested it) |
| Petrovski |
Posted - 05/30/2016 : 08:24:02
Today I've repeated the test. I've put the 320-Plus on a sample stage so it was now ~10 cm away from the X-ray tube's aperture:
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I started again with the tube at max power (60kV/50mA) but as soon as I opened the shutter the 320-Plus saturated and the firmware rebooted.
So I lowered the power to 15/5 and checked the 320-Plus's response while I slowly increased the power. At 40/20 it was well in the 30k CPM range:
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The logged data does not reflect the experiment however. The max CPM on display is not logged, and also it does not show the increase of CPM while I increased the tube power:
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If I had to guess, it seems the firmware was too busy detecting radiation and the data logger task got low priority. Perhaps someone from GQ can confirm this?
Update: actually on a logarithmic scale you can see the first power ramp-up. But after that, none:
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| Petrovski |
Posted - 05/29/2016 : 09:37:41
Well, it's simply lying at the bottom of the enclosure of an X-ray diffractometer (at my work). I can choose between multiple X-ray tube anode materials, and can control the HT generator's power.
I'll repeat this test with data logging set to 1 second interval, I'm sure it will produce an interesting graph. |
| ZLM |
Posted - 05/27/2016 : 22:45:05
Great!
Can you provide detailed information on how you did that? |
