Driving through town and listening to a local 1620 10KW AM station 20
miles away, the hash and birdies from government buildings completely
destroy the reception so nothing is heard. The noise from IT sources
carries about a block or so. Fortunately I live in the country or any
reception on 160 meters would be toast. These high noise locations
are increasing with more and more routers and Cat 5 cable running all
over the downtown buildings. I doubt if it will get any better. The
local power company was going to put in BPL here with Federal funds so
they could read meters remotely while also going into the internet
business with a 100 million dollar grant from NTIA designed for
underserved rural areas. Yet we have 5 active Wi-Max, DSL, and even
direct fiber by private companies. Isn't it just wonderful when the
mother government trys to compete with private industry?
Herb, KV4FZ
On 9/10/2013 7:40 PM, Tom W8JI wrote:
But we should clear up a potential for misunderstanding here. When
we talk
about allowing the noise floor noise to rise, this suggests broadband
noise
emissions limits would be raised. Typical sources of this kind of noise
are switching power supplies, digital devices, and UWB communications
devices. Last time I checked, Ultra-WideBand systems are required to be
bandwidth-limited (using simple filters), and they typically raise the
noise floor in the UHF and higher parts of the spectrum. So power
supplies
and digital devices (computers, routers, etc.) would be the main
culprits,
but I don't understand how you could exempt ham receivers from a rule
concerning them. Nothing can be exempted from noise that covers up
everything.
The linked article does not make much sense to me in perspective of HF
down to the AM band and lower.
The most common sources of noise, by far, are switching power supplies.
A distant second are digital devices connected to long cables or large
wiring systems.
Of all the devices that cannot bother 160 or HF, or especially AM BC,
smart phones and other digital handheld devices are near the very top.
They are so small and have such low power they would not likely be
noticed if hanging right on our antennas.
I agree with other comments that the real issue, and it has been an
issue since the 1980's, is lack of enforcement. We wanted deregulation
and the Government out of our business, and certainly we got what we
wanted with the FCC. :-)
73 Tom
_________________
Topband Reflector
_________________
Topband Reflector
|