[hpsdr] An high dynamic QSD front-end

[Marco IK1ODO]

Hi all,

as a few members of this list already know, I did a lot of work about 
expanding the dynamic range of a QSD mixer.
Some results of my work are in http://www.spin-it.com/sdr/IK1ODO_SDR1.html .
Possibly this may be a good starting point for Phoenix; I am willing 
to cooperate, if possible.

Please have a look at the page and the other two, with more 
measuraments and tests. This may not be the ultimate SDR, but I think 
that the results are quite interesting, and it's simple to implement.

73 - Marco IK1ODO