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<DIV><FONT face=Arial size=2>If we are talking about a passive diode ring mixer
the MMIC is not to provide gain but to teminate unwanted mixing products.
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<DIV><FONT face=Arial size=2>The LT2204 on Merc is likely marginal but toally
zapped by the 55Mhz LPF.</FONT></DIV>
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<DIV><FONT face=Arial size=2>Some of any excess gain can conviently be lost in a
BPF ahead of Merc or the 2nd IF.</FONT></DIV>
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<DIV><FONT face=Arial size=2>Shel CT1IZU</FONT></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=anthonytaylorengg@yahoo.com
href="mailto:anthonytaylorengg@yahoo.com">Anthony Taylor</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=hpsdr@openhpsdr.org
href="mailto:hpsdr@openhpsdr.org">hpsdr@openhpsdr.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Friday, September 10, 2010 11:18
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [hpsdr] New HPSDR card for
VHF/UHF ?</DIV>
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<TD vAlign=top>Further amplification after the mixer may not be required
due to the 20dB ADC driver already present before the ADC, i'm getting
good results with no MMIC after the mixer, adding more gain may degrade
the dynamic range.<BR><BR></TD></TR></TBODY></TABLE>
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