| Summary: | Detection of B-mode polarization from the cosmic microwave background would provide compelling evidence for the inflationary paradigm and has thus become a principal goal for experimental cosmologists during the last 5-10 years. A number of high sensitivity experiments have been developed and many are under construction, including the E and B EXperiment (EBEX), a balloon-borne experiment scheduled to take data in 2010. The design of EBEX is presented here, including the scientific motivation for the experiment, and an overview of all its components, with particular attention paid to the read out electronics for its array of over 1300 biometries detectors. In the read out of such a large array of bolometers, which must be kept at ∼250mK, running many signals down the same wire (i.e. multiplexing) is vital. The digital frequency multiplexing (dfmux) electronics designed and tested at McGill addresses this as well as providing the control required to tune the bolometers and super conducting quantum interference devices (SQUIDs) used in readout. How these electronics accomplish both of these goals is described with an in-depth description of the recently designed tuning algorithms required to take the detectors from initialization to fully-operational. Finally, some tests of the readout system on cold bolometers in a test cryostat are presented. These measurements are encouraging with 98% success rate of automated tuning on a test sample of 47 bolometers. Improvements to achieve a 100% success rate have been proposed and will be implemented for the upcoming integration of the bolometer camera with the telescope in November 2008. A test-flight for the experiment is planned for spring 2009, and the science flight for 2010 from Antarctica.
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