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Re: [Amps] 10dB and propagation

To: amps@contesting.com
Subject: Re: [Amps] 10dB and propagation
From: K3BU@aol.com
Date: Mon, 7 Feb 2005 10:12:25 EST
List-post: <mailto:amps@contesting.com>
In a message dated 2/6/2005 11:12:46 AM Eastern Standard Time, 
david.kirkby@onetel.net writes:

>>Yet refraction of radio waves was understood well before 1980 when you 
wrote that. A Quick look at 'Cornell University's School of Electrical 
Engineering Publications'<<

I do not claim to "inventing" refraction. What I was trying to convey (with 
my rough English) that there is perhaps more refracting - ducting going on than 
just reflecting. Most if not all books at that time were showing way out of 
proportion drawings of globe and ionospheric layers (too high) and "nice" 
bouncy signals. Hardly any mention of ducting on HF.
After the article was published I got bombarded by mails, some saying that I 
am nuts (it ain't so) and some that this is nothing new. I guess depends who 
and how they look and interpret it.
Using my Razor antennas I was able to "see" some things that were not 
generally known and I tried to describe them as best as I could. There is more 
and 
more stuff being confirmed about possible, lets call it "refraducting". See 
Topband reflector about spotlight, skewed path and high angle propagation, 
about 
which I was ridiculed way back. 
>>Non-linear effects can be seen in many materials, but generally need 
high field strengths - not the sort of E or H field you could produce on 
the iosphere with a transmitter on earth. At least that is my 
"gut-feeling" - I may be wrong.<<

Call me old wife, but we have noticed that after the major contest, bands 
seem to be "conditioned" to propagate better for a while, about half an hour 
after the bedlam stops. I had numerous skeds with OK2RZ on 40m right after the 
contest and our signals would take a dive after about 1/2 hour. While at other, 
non-contest times, at the same time we did not see that effect.
If you consider really thousands of kWs and high gain antennas during the 
contests, in view of now knowing about ionospheric heating (HAARP), I would not 
completely dismiss the effect. There might be even selective "heat your own 
frequency" effect. 
Another interesting thing I experienced when trying to see if the same angle 
on receive and transmit applies. By switching stacked Razors and doing RX/TX 
tests my finding was that about 60% of the time it was not the same. Bite me 
for that one :-)  
When we are talking about "non-linear" ionosphere, we are implying properties 
not exactly reciprocal, biderectional or behaving like a coax. Rather than it 
is not simple mechanism and things could seem to be one way, weird signal 
levels and the rest of it.

I haven't been "up there" and measured how the atmo/ionosphere works, only 
able to observe some effects, results and trying to make some sense of it. 
Again, I am pleased to see Rich's notes about 23 dB, however "inacurate" it 
is, it supports rather than denies something that we observed. 
That's why I still fool around with radios, we don't know everything yet :-)


73  Yuri, www.K3BU.us
www.computeradio.us home of Dream Radio One
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