About the Airspy software defined spectrograph

Many thanks to the following sources:

http://www.rtl-sdr.com/tag/airspy/

http://forums.radioreference.com/software-defined-radio/280617-airspy-sdr-sdr-author-6.html

http://www.kmitocty.cz/?p=1709

March 2015 Airspy Radiouser  article by Mike Richards
http://www.pwpublishing.ltd.uk/radio-user/

https://www.google.com/search?q=airspy+sdr+images
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