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Re: Radio communication

To: Bryan Savage <basavage@earthlink.net>
Subject: Re: Radio communication
From: Ralph Forsythe <rf-list@centerone.com>
Date: Fri, 14 Feb 2003 15:56:44 -0700 (MST)
On Fri, 14 Feb 2003, Bryan Savage wrote:

> That sounds very interesting Ralph. RF communication with a car seems to
> work fine up to
> about 140-180 MPH when the S/N ratio appears to drop towards 1. I have
> no idea what the
> xmit power input was in these cases. I suspect it was low (1-10 W).
>
> Bryan

Yeah, I'm thinking legally blast enough RF to get it through.  I don't
know why speed would affect the signal strength since that is more based
on distance and environmental characteristics.  I'm not familiar with how
the electrical properties of a huge body of salt react with radio
communications (other than probably reflecting it), am I missing something
there?  Could it even be static off the body of the car at speed affecting
the transmission?  Just random guesses.  What about the antenna being
pulled back away from the connection to the coax from wind drag?  How were
the vehicles were this was tested set up radio-wise?

I am a former systems engineer for a paging company, and still have access
to their toys.  As I'll be at speedweek, if someone wants to rig their
ride with comm gear I can bring the gear out and maybe help find a
solution, since there aren't a whole lot of places to run near 180mph
around here... :)  (Plus my 4runner just doesn't get that fast, and I
don't have a headset in the bike helmet. Oh yeah, that whole jail thing is
a deterrent too...)

I really think it's something simple that maybe just got overlooked.  RF
doesn't care about 180mph...

- Ralph

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