<html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv=Content-Type content="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 11 (filtered medium)">
<style>
<!--
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman";}
a:link, span.MsoHyperlink
{color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{color:purple;
text-decoration:underline;}
pre
{margin:0cm;
margin-bottom:.0001pt;
font-size:10.0pt;
font-family:"Courier New";}
span.EmailStyle18
{mso-style-type:personal-compose;
font-family:Arial;
color:windowtext;}
@page Section1
{size:612.0pt 792.0pt;
margin:72.0pt 90.0pt 72.0pt 90.0pt;}
div.Section1
{page:Section1;}
-->
</style>
</head>
<body lang=EN-US link=blue vlink=purple>
<div class=Section1><pre><font size=2 face="Courier New"><span
style='font-size:10.0pt'>What about the Elecraft K2 solution: R67 (1k5) and R68 (226R) against ground.<o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>Or in the KPA100: RF Choke of 100uH against ground.<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'>In HB9 we run the “National Mountain Day” contest every July. <o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>It’s a /p 80m CW event over 4h and max. 6 kg for the whole station (without OP).<o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>In 2002 a big thunderstorm with lightning crossed HB9 and damaged several rigs. <o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>Surprisingly more transistors in the PA were damaged compared to the RX frontend. <o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>The simplest solution found were: 50-100k against ground or 1-2.2 uH against ground (It’s 80m only).<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'>73 de Dominik, HB9CZF <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'>PS: in case you read German I can scan 10 pages with many more details.<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'>>A high value resistance to ground to prevent static buildup (100K to 1 <o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>>Meg) in parallel with a spark gap offers no distortion and clamps <o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>>induced surges (not direct hits by lightning, of course). Caps in the <o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>>front end filters should be rated somewhat higher than the spark gap - <o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>>you don't want to use 25V caps in a 70V-protected system!<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'>>Try searching Digikey for "surge arrestor gastube" for EPCOS' offerings. <o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>> The lowest voltage ones ought to be suitable.<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'>>73,<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'>>Lyle KK7P<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>
</div>
</body>
</html>