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Old 01-15-2017, 2:11 PM
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Coyote-Frostbyte Coyote-Frostbyte is offline
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Join Date: Feb 2016
Location: Colorado, New Mexico
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The other evening I was tuning across 28 Mhz when I heard it- the unmistakable sound of Aurora.... That weirdly distorted, practically unintelligible gibberish of a signal, accompanied by its strange squeals and squawks - the signals of Auroral scatter.
Then I recalled I wanted to say something about this- that was 2 months ago, and 6 metre's in particular. .
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I doubt any ham whose spent time on Six hasn't heard it at least once... certainly its effects can be heard on HF. The interesting thing, to me, about it and 6; you can use aurora to your advantage. By pointing a beam antenna North, regardless of where the other station is geographically, will be rewarding. At least 100 watts is generally required, and depending on the aurora, it may be impossible to use broadband modes, like FM. The physics of the spiraling ionized fields, distorted by a Doppler effect, warps any analog signal- and the wider the bandwidth- the worse the distortion... not to mention that each ionized particle becomes its own reflector-- all adding to the bizarre chorus of the signal. Sometimes, by patience, sideband can be used- but it requires a skill at talking slowly and clearly- most hams use old fashioned slow speed CW.
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The lower the latitudes, the less likely the phenomenon... but it does occur frequently to the Lower 48. There are Web sites one can go to see what the current activity is, and operate accordingly....... and from here on, I'm going to steer clear of anymore physics; sufficient to say that Auroras are awesome radio laboratories.
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So if you haven't completed your 6 metre EME station yet ( ) and are impatiently awaiting the return of the E skip, park your beam North and-- who knows??
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........................CF
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For those that want to tackle it, here is a site that gives some of the physics.
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. https://www.ursa.fi/ursa/jaostot/rev...o/enradio.html
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