[Elecraft] OT - FCC Seeks "Noise Floor"

Fred Jensen k6dgw at foothill.net
Tue Jun 21 20:06:00 EDT 2016


Well actually, not quite.  Incidental radiators are the noisemakers such 
a power lines arcing.  They radiate RF but have no need to.  They also 
do it across broad frequency ranges over several tens of MHz.

Unintentional radiators are computers, wall warts and SMPS, plasma TV's, 
and the like.  They generate RF internally for their operation, but do 
not intend to radiate it.  Alas, thanks to James Maxwell, they do.

Intentional radiators are those unlicensed devices that must radiate RF 
to function ... WiFi, Bluetooth, cell phones, etc.  They tend to be 
confined to certain bands [usually ISM bands like 2.4 GHz].  Many are 
spread-spectrum types of signals, and in a narrow receive BW just raise 
the noise floor a bit.

Some intentional radiators are in other than ISM bands.  443.93 MHz, 
familiar to most hams, is full of beeps, squawks, and other very short 
bursts.  They're remote reading thermometers, and other sensors.  Some 
RFID equipment operates on that and a few other frequencies which can be 
a problem for hams near ports, large rail yards, and intermodal yards. 
Pacific Gas and Electric remote-reading meters are said to be around 500 
MHz in a mesh network of some sort.

The TAC in the original link points out that quantitative data on the 
noise floor is sparse at best and very hard to obtain and analyze since 
it depends on so many factors in an almost infinite number of locations.

As to FCC enforcement or the lack of it, in the 50's the Commission was 
very active in enforcement ... especially if it affected commercial 
communications.  Today, the FCC is very much more a "Coordinator of 
Communications" than an enforcement agency.

I've concluded that, "It is what it is," and there aren't many ways to 
quantify noise floor for a finite amount of investment dollars.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the Cal QSO Party 1-2 Oct 2016
- www.cqp.org

On 6/21/2016 10:39 AM, Barry LaZar wrote:
> David,
>     This is interesting. But, how does it relate to the regulations
> already on the books having to do with incidental radiation? That's the
> regulation set that controls conducted and radiated noise from
> powerlines, TV, computers, etc.
>
> 73,
> Barry
> K3NDM



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