This report describes the WR-10 waveguide vacuum feedthrough used in the local oscillator train of the ALMA Band 6 receivers. The vacuum window is a short section of epoxy-filled waveguide. A second identical window spaced ~8g/4 from the first matches the feedthrough over the desired band (73.7-88.3 GHz). The electrical characteristics and leak rates of the epoxy-filled windows are compared with those of the simpler but less satisfactory Mylar window.
View a pdf version of ALMA Memo #536.
Last modified: 2005-09-15
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