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An X-ray machine has been built from a vacuum diode and then from real 1970s X-ray tube, overclocked TV transformer and a hospital X-ray screen. Some X-ray photos have been taken. As of 12/2014, the high voltage supply is broken and efforts are on building a better one.
Update: Since 12/2015 we got as gift old X-ray transformer but we must dry transformer first before filling by oil. Without insulating oil transformer burns up quickly. As insulating oil we bought 5l of special transformer oil Paramo MOGUL TRAFO CZ-A (thanks all for donations :)) https://eshop.paramo.cz/data/VyrobkovaDokumentace/ti_trafo_cza_z5.pdf
Jenda wrote a final exam work at the high school about it: http://jenda.hrach.eu/brm/ct.pdf
photos:
parallel_beam.py, mirror, patch:
30a31 > import matplotlib.pyplot as pl 383c384 < if (f_type.lower () == "none"): --- > """if (f_type.lower () == "none"): 387c388 < return filtered_proj --- > return filtered_proj""" 415c416,417 < raise ValueError ("rho_filter: Unknown window type: %s" % f_type) --- > #raise ValueError ("rho_filter: Unknown window type: %s" % f_type) > window = 1 419c421 < --- > print(filt) 428,429c430,432 < for i in range (proj_fft.shape [1]): < proj_fft [:, i] *= filt --- > if (f_type.lower () != "none"): > for i in range (proj_fft.shape [1]): > proj_fft [:, i] *= filt 435,436c438,442 < filtered_proj.resize ((proj.shape [0], filtered_proj.shape [1])) < --- > print(proj.shape [0], filtered_proj.shape [1]) > #filtered_proj.resize ((proj.shape [0], filtered_proj.shape [1])) > arr=filtered_proj[:proj.shape [0]][:proj.shape [0]] > print(arr.shape[0], arr.shape[1]) > filtered_proj=arr
We have two old X-ray tubes manufactured by Chirana in 1970 but the smaller one is broken (R.I.P). Actually we use the larger one DOK-70kVv
We use as screen original X-ray screen Agfa Ortho Regular 24×30 mounted in ClubMate box with mirror to prevent damage camera by heavy x-ray beam.