[amsat-bb] Re: Fw: Re: More Clutter on 2.4 GHz

[John Champa]

Also, when a Part 15 station uses a dish, all that ERP only affects you when 
the dish is pointed directly at you...for the most part....and those 
beamwidths are very narrow for a 24 dBi dish.

73, John - K8OCL


>From: "John B. Stephensen" <kd6ozh at comcast.net>
>To: "Nate Duehr" <nate at natetech.com>, "Tony Stone" <w4tas at gte.net>
>CC: amsat-bb at amsat.org
>Subject: [amsat-bb] Re: Fw:  Re: More Clutter on 2.4 GHz
>Date: Mon, 9 Oct 2006 22:56:01 -0000
>
>If you're staying above the satellite segment then you're not creating
>problems for amateur satellite users. The long-term problem is that 
>non-hams
>won't care as much, especially as usage increases, and 
>47CFR97.303(j)(2)(ii)
>says that we must accept interference from all other users so we can't 
>force
>them to change frequencies. Interestingly, there is no statement that hams
>can't cause interference to unlicensed devices.
>
>73,
>
>John
>KD6OZH
>
>----- Original Message -----
>From: "Nate Duehr" <nate at natetech.com>
>To: "Tony Stone" <w4tas at gte.net>
>Cc: <amsat-bb at amsat.org>
>Sent: Monday, October 09, 2006 21:45 UTC
>Subject: [amsat-bb] Re: Fw: Re: More Clutter on 2.4 GHz
>
>
> > Tony Stone wrote:
> >> The part 15 rules for 2.4 GHz operation state that a maximum 
>transmitter
> >> output of 1 watt with a 6 dbi omni antenna is legal. This is 4 watts
> >> eirp.
> >> With a directional antenna you must decrease your transmitter power
> >> 1 db below 1 watt for every 3 db antenna gain over 6 dbi.
> >>
> >> Confusing as this may seem, it means that you can have 250 milliwatts
> >> of transmitter output with a 24 dbi gain antenna. That is 18 db over
> >> the original 6 dbi which is 6 units of 3 db each. This means that the
> >> transmitter power must be reduced from 1 watt to 250 milliwatts (6db).
> >>
> >> This is an effective isotropic radiated power of 64 watts and is
> >> perfictly
> >> legal.
> >>
> >> Check the gain of a 36 inch dish at 2.4 GHz and do the calculations to
> >> see if it is legal or not.
> >>
> >> 73
> >>
> >> Tony
> >> W4TAS
> >
> > Tony -
> >
> > Sorry if I got it wrong.  I was going off of some of Cisco's
> > certification documentation for certifying their Access Points, perhaps
> > they're being overly conservative on their numbers to assure
> > certifications.
> >
> > I couldn't find my old link to the REAL rules so I might have been a bit
> > overzealous in my numbers on the low side.
> >
> > Still: In reality it's a free-for-all... you could blast just about
> > whatever you want point-to-point with gain antennas and there'd be
> > little way to find that you were doing it, and even less desire to do
> > anything about it.
> >
> > Sorry to the list -- mostly the only reason it relates to anything
> > Satellite-related is the general noise level on 2.4 GHz, and I'm
> > creating more "noise" on the list than that... (GRIN).
> >
> > Happy to take this offline if someone wants to continue.
> >
> > Nate WY0X
> > _______________________________________________
> > Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
> > Not an AMSAT-NA member? Join now to support the amateur satellite 
>program!
> > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>
>_______________________________________________
>Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb