[Milsurplus] NVIS Propagation Model

[J. Forster]

>From the VMARS (UK) Group, FYI.

-John

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---------------------------- Original Message ----------------------------
Subject: [vmars] Re: NVIS
From:    "Michael Buckley" <M1CCF at talktalk.net>
Date:    Wed, November 11, 2009 3:26 am
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NVIS propagation prediction model
Posted by: "George Lane" glane at erols.com   glaneprop
Tue Nov 10, 2009 2:08 pm (PST)


Greetings:

This message is prompted by the sad news I received today that the
renowned Ionospheric scientist, Ernie Smith, died recently. He mapped
the worldwide E layer and the sporadic E layer maps. This almost ends
all of the scientists and engineers who worked on the US Government
Ionospheric systems performance prediction programs. When the USA
entered the war in 1941, there was a frantic effort begun in the War
Department in Washington DC to develop a prediction method for planning
and operating HF links all around the world. By the end of the war, the
US Army Radio Propagation Agency had been established for supporting our
strategic HF worldwide communications links. In the 1950's Pres.
Eisenhower established the Environmental Science Services Administration
(ESSA) at Boulder, CO. It was here in the mid-1960's that the Institute
for Telecommunication Sciences (ITS) developed the first full HF Skywave
Performance Computer Model (ITSA-1). VOACAP is a direct decendent of
that program which had required the largest computers in the nation.
The current VOACAP model runs on a PC and is very fast thanks to Greg
Hand who used to work for ITS until he retired.

At this time there are very few of us still alive who know about this
program. Greg Hand is now retired and he has set up a web site where
you can still download VOACAP for free. He has also put up the ordering
information for the Rockwell Collins VOACAP Users Guide which is now
FREE on CD with a $5 or $10 shipping charge.

Time is marching on and some day all of this will go away as neither
Greg nor I are funded to do any of this. I am really happy to know that
Rockwell is now giving away the User's Guide.

If you are really serious about NVIS, then I think you need to design
your operations using a prediction program that is proven to work after
67 years of development. Sooner or later this free service will die, too.

http://greg-hand.com/pc_hf/rockwell/

If you want the program for free download go to greg-hand.com/pc

Neither Greg nor I stand to make a dime whether you take advantage of
this or not. We both believe it is important to return to the HF
community what has been developed and now abandoned by the US Government
which views HF as dead already.

Regards,

George Lane

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