[RFI] Weather Station on 433.92? (Cortland Richmond

[David Garnier]

Hi Cortland,

I have written about these devices before...

Having briefly looked at Part 15 regulations for transmitting devices,
they scary the crap out of me... I don't have to deal directly with these
devices at work yet, the 433.92 MHz frequency sounds awfully like
an ISM frequency slot. (Years ago we used to test product @ 3 V/m
80% AM modulation on our OATS site, I think that's the frequencies
called out by CISPR11.)

My rudimentary understanding of the regs for Part 15 transmitters is
1) 3 meter limit for RE that "falls off" (some curve) with frequency,
2) Can darn near operate anywhere _however_, 3) Without causing
"harmful interference" (whatever the FCC definition of the day is.)

Do I got it right?  I sure there's other folks who work in a test houses
and are more intimately knowledgeable with them than I am...  I love
this business.  ;-)

(( Lin/KJ6E, Ed Hare for sure would know the answer since it intrudes
into the bottom of 450 band.  _If you think this is bad_, look at the 
905 MHz
ham band once. ))

dave garnier - wb9own

========================================

Date: Sun, 8 Apr 2007 20:35:04 -0400
From: "Cortland Richmond" <ka5s at earthlink.net>
Subject: Re: [RFI] Weather Station on 433.92?
To: rfi at contesting.com
Message-ID: <380-220074190354734 at earthlink.net>
Content-Type: text/plain; charset=US-ASCII

Lin, 

That falls under Part 15.   15.209 says 200 microvolts per meter at 3
meters, so it's pretty loud.    A Part 15 user is responsible for stopping
interference to a licensed one, of course.  That's no help if you're both
of 'em!

Cortland
KA5S