{"id":320,"date":"2023-07-11T12:47:54","date_gmt":"2023-07-11T10:47:54","guid":{"rendered":"https:\/\/www.bexus.org\/?p=320"},"modified":"2023-07-11T12:49:08","modified_gmt":"2023-07-11T10:49:08","slug":"successful-test-of-a-geiger-muller-counter-in-vacuum","status":"publish","type":"post","link":"https:\/\/www.bexus.org\/index.php\/2023\/07\/11\/successful-test-of-a-geiger-muller-counter-in-vacuum\/","title":{"rendered":"Successful Test of a Geiger-M\u00fcller Counter in Vacuum"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">For a Weatherballoon mission lead by the <a href=\"https:\/\/www.rhs-kiel.de\">Ricarda-Huch-Schule<\/a> we prepared and tested a Geiger-M\u00fcller Counter  module.  The challenge is to operate the high voltage supply of the tube in the partial vacuum of the stratosphere. We may encounter a <a href=\"https:\/\/en.wikipedia.org\/wiki\/Corona_discharge\">Corona discharge<\/a>, which may destroy the electronics or at least impact the measurements.  We are all happy to leave Corona behind us.  The second issue is the internal pressure of the tube.  We passed all tests.  Down to 1mbar pressure the unit worked flawlessly.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4656-1024x768.jpg\" alt=\"\" class=\"wp-image-318\" srcset=\"https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4656-1024x768.jpg 1024w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4656-300x225.jpg 300w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4656-768x576.jpg 768w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4656-1536x1152.jpg 1536w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4656-2048x1536.jpg 2048w\" sizes=\"auto, (max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">First, the tube was tested individually. It survived low pressure.  The HV was calibrated to 400V as prescribed in the <a href=\"https:\/\/github.com\/SensorsIot\/Geiger-Counter-RadiationD-v1.1-CAJOE-\">manual<\/a>. Then we removed the calibration connecter and a power connector that were too close to the HV electrode of the tube.  The board was coated twice with a space grade 2-component silicone encapsulant, in particular the HV supply and the area close to the HV end of the tube.  We obtained an insulation distance of about 4cm.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/Paschen-Air-40mm-1024x768.png\" alt=\"\" class=\"wp-image-321\" srcset=\"https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/Paschen-Air-40mm-1024x768.png 1024w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/Paschen-Air-40mm-300x225.png 300w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/Paschen-Air-40mm-768x576.png 768w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/Paschen-Air-40mm.png 1200w\" sizes=\"auto, (max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">The <a href=\"https:\/\/en.wikipedia.org\/wiki\/Paschen%27s_law\">Paschen Curve<\/a> tells us that we should be good down to a few mbar.<\/p>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-1 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" data-id=\"317\" src=\"https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4657-1024x768.jpg\" alt=\"\" class=\"wp-image-317\" srcset=\"https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4657-1024x768.jpg 1024w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4657-300x225.jpg 300w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4657-768x576.jpg 768w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4657-1536x1152.jpg 1536w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4657-2048x1536.jpg 2048w\" sizes=\"auto, (max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"1024\" data-id=\"316\" src=\"https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4658-768x1024.jpg\" alt=\"\" class=\"wp-image-316\" srcset=\"https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4658-768x1024.jpg 768w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4658-225x300.jpg 225w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4658-1152x1536.jpg 1152w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4658-1536x2048.jpg 1536w, https:\/\/www.bexus.org\/wp-content\/uploads\/2023\/07\/IMG_4658-scaled.jpg 1920w\" sizes=\"auto, (max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><\/figure>\n<\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">First, we tested in a glas chamber, to visually observe the test. But that pump could not go below 60mbar.  Then we used our regular thermal vacuum test stand for balloon missions, shown above.  The test was performed at room temperature.  We used only the rough vacuum pump, which took the chamber pressure down to 1mbar.  The output of the module was monitored with an oscilloscope.  A \u00b2\u2070\u2077Bi souce was place inside the chamber to increase the counting activity.  It worked well.  Unfortunately, we did not take any pictures.   <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Vio did the coating, see the log sheet above.  Ronja soldered the feedthrough harness and performed the Vaccum tests. S\u00f6nke observed radiation safety. Matti provided the counter module.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Now we are waiting for the <a href=\"https:\/\/www.stratoflights.com\/tutorial\/wetterballon-tools\/flugroutenvorausberechnung\/\">flight forecasts<\/a> to predict a landing site on land.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>For a Weatherballoon mission lead by the Ricarda-Huch-Schule we prepared and tested a Geiger-M\u00fcller Counter module. The challenge is to operate the high voltage supply of the tube in the partial vacuum of the stratosphere. We may encounter a Corona discharge, which may destroy the electronics or at least impact the measurements. We are all happy to leave Corona behind us. The second issue is the internal pressure of the tube. We passed all tests. Down to 1mbar pressure the unit worked flawlessly. First, the tube was tested individually. It survived low pressure. The HV was calibrated to 400V as prescribed &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/www.bexus.org\/index.php\/2023\/07\/11\/successful-test-of-a-geiger-muller-counter-in-vacuum\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Successful Test of a Geiger-M\u00fcller Counter in Vacuum&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_crdt_document":"","footnotes":""},"categories":[9,8,11],"tags":[],"class_list":["post-320","post","type-post","status-publish","format-standard","hentry","category-hardware","category-sensors","category-weatherballon"],"_links":{"self":[{"href":"https:\/\/www.bexus.org\/index.php\/wp-json\/wp\/v2\/posts\/320","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bexus.org\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bexus.org\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bexus.org\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bexus.org\/index.php\/wp-json\/wp\/v2\/comments?post=320"}],"version-history":[{"count":1,"href":"https:\/\/www.bexus.org\/index.php\/wp-json\/wp\/v2\/posts\/320\/revisions"}],"predecessor-version":[{"id":322,"href":"https:\/\/www.bexus.org\/index.php\/wp-json\/wp\/v2\/posts\/320\/revisions\/322"}],"wp:attachment":[{"href":"https:\/\/www.bexus.org\/index.php\/wp-json\/wp\/v2\/media?parent=320"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bexus.org\/index.php\/wp-json\/wp\/v2\/categories?post=320"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bexus.org\/index.php\/wp-json\/wp\/v2\/tags?post=320"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}