[Amps] 10dB and propagation

[Michael Tope]

----- Original Message -----
From: "Jeremy Alexander" <oaxaca at oregoncoast.com>
>
> "The power emitted by these ionospheric heaters is QRO in terms of
man-made
> radiated power but is only a fraction of the energy which the ionosphere
> receives from the Sun."
>
>
> Reference is being made to Solar energy per cubic whatever. I think if you
> look at solar energy at any hf wavelength, you will find the power density
> no where near a kW per m^3, only these power levels are realized in the
> upper end of the EM Spectrum. Perhaps most strongly, near-IR and up. I
> believe this statement is usually used to describe the Sun's total, DC to
> Daylight+ power density, in our breathable atmosphere.
>

That is quite correct, but it is precisely the energy in the
X-ray/UV regime that effects the ionosphere, so I don't think
it's so imprecise to include the energy in the upper wavelengths
when comparing solar effects with a system like HAARP.

> Having worked on the HAARP with the Brown and Root boys, the thermopile
side
> of the construction, I find the above a bit incorrect. After copying their
> CW broadcast on HF when they turned it on, and measuring 0.2 milliVolt
> signals from it in Idaho, I would say she is quite robust, especially at
> NVIS radiation patterns.

Don't forget that the effective aperture of an HF antenna is
many square meters, so a power density of microwatts/cm^2
can still add up to a big signal at your RX terminals.

> Anyone that has watched the HAARP in ops, would Never tell you it does NOT
> change the ionosphere. Power density above the facility can approach
levels
> that the beam pattern through atmospheric gases, well below the clouds can
> be seen as "warmer" air through an IR viewer.
>

At tropospheric altitudes you are much closer to the transmitter
so power density is much higher than at say 100 KM where
you get into the ionosphere. So this is not suprising, especially
when you consider that they are capable of ERPs approaching
a Gigawatt.

> The HAARP is a fascinating device. In ops, and modulated at say 22 hz,
these
> data easily travel the entire globe penetrating the oceans in the southern
> polar regions. It's probably the best comms the Navy has ever had. A great
> way to listen to this stuff is simply couple your biggest chunk of
> wire/ferrite directly into your sound card and run a software like
Spectrum
> Lab... absolutely fascinating! Weak signal at its finest!
>

Yes, a pretty cool way to communicate.

73 de Mike, W4EF...............

> 73 to all and thanks for letting me into this way to busy reflector!
>
> Jeremy w7eme
> http://www.oregoncoast.com/oaxaca
>