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Hi Cliff,<BR>
<BR>
I've been waiting until I can empirically test audio performance before I complete my post. Right now I'm having trouble (as reported by others) with noise when using the Penelope microphone input. <BR>
<BR>
I can confirm that interfacing the amp is straight forward and unmodulated output looks good. I measured output of a tad over 10W depending on drive from Penelope. As expected, you will need to filter the output (or the next stage if you are using this board as a driver) as there are unwanted harmonics. I recommend switching the amp on with a tx keying circuit (Pin 13 on Penny's 25pin) rather than relying on the the SDR preamp's RF detection circuit as that will produce a more reliable way to vary output power.<BR>
<BR>
73,<BR>
Dan (N7HQ)<BR><BR><BR>
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From: boatguy1964@gmail.com<BR>To: hpsdr@hpsdr.org<BR>CC: dquigley@msn.com<BR>Subject: K5OOR SDR Preamp<BR>Date: Mon, 26 Jan 2009 13:44:34 -0600<BR><BR><BR>
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<P class=EC_MsoNormal><FONT face=Arial size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Dan, </SPAN></FONT></P>
<P class=EC_MsoNormal><FONT face=Arial size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"> </SPAN></FONT></P>
<P class=EC_MsoNormal><FONT face=Arial size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I just ordered one of Virgil’s K5OOR SDR preamps from HF Projects and look forward to getting it built. I saw the notes that you made regarding the buildup, and haven’t seen anything about it, since then. I was wondering if you might give any impressions that you have, now that you have gotten it (I assume) integrated, and are using it.</SPAN></FONT></P>
<P class=EC_MsoNormal><FONT face=Arial size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"> </SPAN></FONT></P>
<P class=EC_MsoNormal><FONT face=Arial size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">73,</SPAN></FONT></P>
<P class=EC_MsoNormal><FONT face=Arial size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"> </SPAN></FONT></P>
<P class=EC_MsoNormal><FONT face=Arial size=2><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Cliff-KE5FJV </SPAN></FONT></P></DIV></body>
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