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<div class=Section1><pre><font size=2 face="Courier New"><span
style='font-size:10.0pt'>><i><span style='font-style:italic'> According to the comments in the code, the frequency sent to Mercury by PowerSDR is "the indicated frequency less the 9kHz IF". As a consequence, the firmware adds 9kHz to the frequency to determine which filter to engage.<o:p></o:p></span></i></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'><o:p> </o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>> I guess I'm lost a little here... what 9kHz IF?<o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'><o:p> </o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>The 9 KHz is the offset that was/is used by the SDR-1000 to keep the frequency of interest away from the 0-Hz "no-man's land" where there is a lot of noise present in sound-card based QSD systems.<o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'><o:p> </o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>Thankfully, HPSDR does away with that issue. Hopefully, the HPSDR version(s) of PowerSDR will be modified to do away with this frequency error being sent to Mercury, which is causing the incorrect switching points with Alex.<o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'><o:p> </o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>Bruce, N1RX<o:p></o:p></span></font></pre>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
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