[VHFcontesting] SPLAT!

[James Duffey]

The ARRL internet surfer, WA1LOU, has just posted on the ARRL page an  
interesting summary of a web page called SPLAT!:

< http://cs.ecok.edu/~bw/SPLAT/ >

SPLAT! calculates path loss for frequencies from 20 MHz to 20 GHz. You  
input your location, antenna height, and frequency. It will calculate  
a coverage pattern for you using the Longley-Rice Irregular terrain  
model. It will calculate the path loss between two stations and  
display the path loss as a function of distance between two stations.

You need to input your lat and lon and it adds it to a database of  
other stations. You can calculate the path loss between any two  
stations that are on the list.

This is a web hosted version of the LINUX program SPLAT!, with which I  
was not familiar.

I entered a couple of my favorite rover sites and the results seem to  
qualitatively agree with what I have experienced. The path loss  
calculation lets you see what you need to do to work those stations  
that never seem to come back to you. It also lets you evaluate  
potential rover sites against working the usual contest suspects.

Using this you can calculate the effects of antenna height and sloping  
ground.

The are a couple of things one needs to look out for, I noticed that  
it calculates the path loss assuming vertical polarization and  it  
defaults to the temperate climate model. Assuming vertical  
polarization probably is a few dB down on horizontal polarization for  
troposcatter and in some locals a better climate model should be used.  
The desert option would be nice here in NM. The Linux version allows  
one to change these things, but you also need to download a whole lot  
of terrain data that the web page author has already done.

Try it out, it is a great tool for planning roves. - Duffey
--
KK6MC
James Duffey
Cedar Crest NM