If I read Nick's 2nd doc correctly, the station's saturable core reactor was able to follow the FSK mark and space freqs to keep the antenna resonant for each. Impressive for "bearskin and stone knives" technology.&nbsp;<div><br></div><div>73 de</div><div>Gene Smar AD3F&nbsp;</div><div><br></div><div><br><br><div id="ymail_android_signature">Sent from my Radio Shack TRS-80 model 100 laptop</div> <br> <blockquote style="margin: 0 0 20px 0;"> <div style="font-family:Roboto, sans-serif; color:#6D00F6;"> <div>On Sat, Dec 17, 2022 at 1:41 PM, Ken Krausgill via MRCA</div><div>&lt;mrca@mailman.qth.net&gt; wrote:</div> </div> <div style="padding: 10px 0 0 20px; margin: 10px 0 0 0; border-left: 1px solid #6D00F6;"> ______________________________________________________________<br clear="none">MRCA mailing list<br clear="none">Home: <a shape="rect" href="http://mailman.qth.net/mailman/listinfo/mrca" target="_blank">http://mailman.qth.net/mailman/listinfo/mrca</a><br clear="none">Help: <a shape="rect" href="http://mailman.qth.net/mmfaq.htm" target="_blank">http://mailman.qth.net/mmfaq.htm</a><br clear="none">Post: mailto:<a shape="rect" ymailto="mailto:MRCA@mailman.qth.net" href="mailto:MRCA@mailman.qth.net">MRCA@mailman.qth.net</a><br clear="none"><br clear="none">This list hosted by: <a shape="rect" href="http://www.qsl.net" target="_blank">http://www.qsl.net</a><br clear="none">Please help support this email list: <a shape="rect" href="http://www.qsl.net/donate.html" target="_blank">http://www.qsl.net/donate.html</a> </div> </blockquote></div>