magicsound MFMP

  • Male
  • from Santa Cruz, California USA (UTC -8)
  • Member since Jul 19th 2015
  • Last Activity:
Posts
369
Likes Received
495
Points
2,401
Profile Hits
2,750
  • magicsound

    Post
    (Quote from kirkshanahan)


    No Kirk, it was a test of the paper itself, to confirm that it did not produce detectable radiation away from the vicinity of the cell. Your proposed leaching behavior, though possible, is both less likely and more difficult to…
  • magicsound

    Post
    Below is the final event log of this test run (#1b). Additional details can be found in my online experiment log at https://goo.gl/4pW1T8

    J5 Test 1b Oct. 15-16 2018 Times CET (UTC+1)

    23:54 paper +SS placed on detector

    00:02 cover removed
    00:15 …
  • magicsound

    Like (Post)
    The situation so far. Again, preliminary OCR data:


  • magicsound

    Like (Post)
    magicsound

    There must be a 4-5 minute delay in the video stream or so because the count rate took quite some time to start decreasing and the provided times didn't seem to exactly match what I was seeing. EDIT: however I just realized that the time…
  • magicsound

    Post
    (Quote from can)


    Good idea. The running-average code for the DAQ needs to be reviewed. I looked at it briefly in the course of my adopting the project, but didn't give it the rigor needed.
    The pancake detector is now enclosed in a large anti-static…
  • magicsound

    Post
    (Quote from can)

    Yes, at 00:33 on your plot I covered the GMC detector with 1 cm of laminated lead. The count initially went low, then gradually increased by ~ 5-8 CPM. This may be due to secondary emission from the lead resulting from cosmic ray hits.…
  • magicsound

    Post
    (Quote from Bruce__H)

    It's far to delicate to be wiped, and has an Al screen to protect it. No attempt was made to remove dust from the detector, the test paper, or the metal plates during any of the tests.
    If I can find a big enough static shield bag,…
  • magicsound

    Post
    The test paper was put in place with the stainless steel cover, at 21:54 UTC. The GMC count dropped from ~30 to ~28 CPM (5 minute moving average).
    This is within the noise bounds of the background level, typically 26-31 CPM

    The sample was removed at…
  • magicsound

    Post
    After the usual struggle with Remote Desktop, I have the video stream running:
    https://www.youtube.com/watch?v=96YDyEQVZAg


    Note that the cell current is now shown in milliamps, rather than amps as labeled. The PA 1000 power monitor is set to low-power…
  • magicsound

    Post
    (Quote from kirkshanahan)


    I cut and folded a fresh strip of printer paper, taken from a closed ream package. I left the paper sitting face-up for ~12 hours next to the lead cave that is part of the test bench, about 20 cm from the cell. The test paper…
  • magicsound

    Post
    (Quote from JohnyFive)


    OK. 4.2 mA @ 11.8 V 50 mW

    Radiation test tomorrow 15 Oct 18:00 UTC
  • magicsound

    Post
    The cell resistance has continued its gradual increase. It's now at nearly 2 k ohms, measuring 1.8 mA @ 3.5 volts for ~6.6 mW power.

    Electrolyte appearance and level have not changed since my last report.

    AlanG
  • magicsound

    Post
    (Quote from Bruce__H)

    Yes, thanks for catching my goof - fixed now.
  • magicsound

    Post
    (Quote from StephenC)


    I'll be doing more tests for sure. But this is a slow experiment (especially in the preparation phase), so you won't get instant entertainment-on-demand.
    Regarding your request for pictures, the appearance hasn't changed since the…
  • magicsound

    Post
    (Quote from Peter)


    Yes, you are correct. The electronics package is a GQ GMC-320+, a relatively inexpensive unit I selected initially for its USB interface. It's not open-source so the schematic isn't made available. When I adapted it for the LND7317…
  • magicsound

    Post
    (Quote from nickec)


    I was motivated to perform a control test of the paper by Kirk's comments on paper chemistry. This test seems to have not produced detectable radiation, using the same measurement process as the the "live"test.

    My expectation was…
  • magicsound

    Post
    can  

    The time zone for the lab computer was set to CET for some reason in the past, and not noticed until the test had started.

    Rather than change it mid-stream I left it for the entire run.

    Following suggestions made earlier, I did a null run, using…
  • magicsound

    Post
    (Quote from can)


    Nope, due to the length of the experiment, I chose the 10 second interval. So another lesson learned here - do separate high-resolution data logging for the test interval of interest.

    Thanks for adjusting the graph, looks more correct…
  • magicsound

    Post
    The data files for the background and active runs are now available as zip archives:

    background: https://drive.google.com/open?…OWbRdC0cMyAvuf_7QgKYjAVGv

    active run: https://drive.google.com/open?…QwIkNTnAHXPPF6kbo2BXMTa3a
  • magicsound

    Post
    (Quote from JohnyFive)


    As was correctly pointed out by Robert Horst, Mica-window pancake GM detectors are very sensitive to false readings from static charge at the mica surface.
    The one I use (LND7317) is expensive ($200) and the mica diaphragm is very…