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<DIV><FONT face=Arial size=2>Hi Francis,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>You asked </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>"<FONT face="Times New Roman" size=3>What is the
front end of this FPGA machine you guys are building.?"</FONT></FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>There are two options being considered at the
moment. The first is direct A/D at the antenna using the Mercury board ( see <A
href="http://hpsdr.net">http://hpsdr.net</A> under Mercury for a brief
description) and a more conventional mixer + local oscillator down
converter to the Janus "sound card replacement" A/D converter.
</FONT></DIV>
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<DIV><FONT face=Arial size=2>At the moment it looks very unlikely that the mixer
will be a QSD due to the 20dB odd increase in NF from 2 to 30MHz that this mixer
suffers from. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I'm presently working on a replacement mixer, still
using bus switches, that does not have this problem. Early results are very
encouraging. More details to follow.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>73's Phil..VK6APH </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
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