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Old 11-14-2016, 3:03 PM
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Join Date: Nov 2003
Location: Downsouthsomewhere
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Originally Posted by Coyote-Frostbyte View Post
Ah !, Neat- the topic swings to the exotic... Moon Bounce, meteors... and one not yet mentioned- I'll introduce- Aurora....
Of the three, Moon Bounce, or EME, fascinates me the most. Truly, if you are the ham that can assemble and master a station capable of communicating via EME on 50Mhz you are in a League Unique... I stand with bow'd head in your presence. At amateur power levels, things have to be so cutting edge techy that its borders on the obsessive- but then I should not talk.
In university days I had the opportunity to operate a government station that boasted a lot (!) more power output than ham radio-- high power into a large dish... this was not on low band vhf (and to this topic, 50Mhz,) but in the near microwaves... During off-hours, unrelated to what we were supposed to be doing with that station, we students would steer the dish at the moon and 'ping it' ('kerchunk" it?-- smiling; after all, the moon is a repeater, albeit a huge passive one.) The +2 second round trip delay was haunting. No one doubts the speed of light, and in our terrestrial environment we just assume everything is instantaneous-- to this day, this remains for me,- the most poignant example in physics of light speed.
We had the capability of modulating our beam with analog voice. The return signals sounded very eerie-- for consider that big round reflector that returns them.... the difference in distance between the lunar poles and its equator induce a distortion in the completed signal's path.... echoey voices return, delayed by seconds, coming from outer space. (Now visualize a small group of grad students with their cylinder-of-helium-of- a-radio station, making like the Munchkins singing 'Follow the yellow brick road' in the Wizard of Oz.... your tax dollars hard at work!)
I admire anyone who will devote their energy's and resources to their hobby to achieve something like this on Six..... Its what makes ham radio very special.
I have some more about Six, aurora and meteors, but later ....
There's something about young people and gas... I 'spose helium was acceptable if nitrous oxide wasn't immediately available. My grad school had neither, and was considerably more boring.

Interesting phenomenon on echos. I always wanted to play with EME, but several thousand miles east of you in "the quiet zone." I have no practical use to do so, though.

Interesting theoretical - how would this planar (?) distortion affect, say, an OFDM signal that one might want to recover and demodulate?

I've heard auroral propagation several times and worked a few CW contacts in the 80s. I've also heard some signals bounced from meteor trails, but only during contests. Gee, we need to get the activity back up so weak signal is popular again!
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