&quot;It&#x27;s not unheard of to make trans-Atlantic contacts using 100mW, by bouncing the signal off the ionosphere. It&#x27;s possibly to reach most of the globe on 25W via PSK31, with sound cards handling the signal processing.&quot;<p>That&#x27;s freaking wild. I remember my brief forays into the subject also had me fascinated with the idea of meteor burst communication where I was bouncing stuff off exploding meteors. Haha. With further digging, the source of my first link was surprising:<p><a href="https:&#x2F;&#x2F;www.nsa.gov&#x2F;public_info&#x2F;_files&#x2F;cryptologic_quarterly&#x2F;meteo_burst.pdf" rel="nofollow">https:&#x2F;&#x2F;www.nsa.gov&#x2F;public_info&#x2F;_files&#x2F;cryptologic_quarterly...</a><p><a href="http:&#x2F;&#x2F;www.dtic.mil&#x2F;dtic&#x2F;tr&#x2F;fulltext&#x2F;u2&#x2F;a228641.pdf" rel="nofollow">http:&#x2F;&#x2F;www.dtic.mil&#x2F;dtic&#x2F;tr&#x2F;fulltext&#x2F;u2&#x2F;a228641.pdf</a><p>The second wasn&#x27;t as DTIC is one of the most badass, if little-known, resources for technical information. Obscure, but great, insights buried in that organizations records.