As to your LED transmitter observation, I have only a UHF two-way radio in my automobile, so I haven't noticed the "LED effect" on VHF high band. They have lots of LED traffic lights in my area, so that part of the equation is in place. & don't forget about all those red LEDs in automobile tail lights now. I haven't noticed anything from the LEDs directly on FM broadcast channels either, including IBOC stations, but that is more a reflection of our having such strong broadcast signals in my area of the country.
In answer to your other observation, yes, the FCC doesn't give a twiddly-damn about the RF spectrum or its purity. I think that this trend started well over a decade ago, & it is fueled by deeply-held policyowner positions within the Commission. First, they badly require to get out of the regulatory enforcement business. They don't get any major brownie points or funding from Congress for jogging the Field Enforcement Bureau (or whatever it is called now), spectrum enforcement is a bottomless pit for them, & it is a never-ending chore. They would auction the spectrum off & tell the happy purchaser, "You look after the cleanliness of *your* bands! We are outta here!"
The second is the deeply-held regulatory notion that "cellular transmission" with its concurrent frequency re-use is the highest & best use of the spectrum. In case you do cellular, you don't must worry much about the ambient noise level as the transmitters are always proximate to the users. The cellular regulatory model is at work not only in public land mobile, but also in private land mobile (where it is very hard to get new PLMRS licenses for wide-area mountaintop or major tower stations, & in case you do get about the most station you can then run is "walkie talkie" power levels. & in broadcasting (LPFMs & LPTVs, which also conveniently use up all obtainable channel slots). & in unlicensed consumer Part 15 wireless LANs. "Et cetera, et cetera, et cetera," as the King of Siam would say.
Don't know whether you caught it at the time, but a few years ago the Commission floated an NPRM which proposed to *allow* interference sources onto licensed channels (in this case, microwave), using an idea known as the defined "Interference Temperature!" The idea was that "smart radios" in the interference generator source would "know" when the source had gone bridge far & would then shut itself down. Lacking that degree of equipment capability by the interferers, the licensee of the channel could always monitor & scream when the measured "interference temperature" rose past established limits.
The industry quickly shot that *^@(&^ idea down!
As soon as some clever businessman figures out a use for the three degrees Kelvin cosmic microwave background radiation, it will be quickly licensed & finally auctioned off.
So, driven by these philosophical points, the Commission now says, "Please proceed to trash the spectrum with lots of unlicensed low power devices, singing power lines, chirping power meters, high speed digital logic with femtosecond switching times (I exaggerate, but not by much!), screeching LEDs. They don't care, & they don't enforce the law here in Dodge City any longer!"
You & I, being elderly timers in this art & science, understand the invaluable resource that the RF spectrum represents & they respect it & they do what they can to maintain it in lovely working shape. The Commission, in later years, has been directed & run by lawyers, economists, & politicians who don't know the physics behind electromagnetic transmission, have not of the "vision thing" for the future non-economic makes use of for which quiet spectrum could be employed, & think about the spectrum mostly as an exploitable economic lovely. What would you expect?
Adding to this outrage, there is much transference of communications today from wired to wireless modes. Most people don't require "Web service to the belly-button!" Now my eleven year-old granddaughters are getting their own cell rings. Give me a (&#%$@& break!
Lots of, lots of services could be well & cheaply provided by wire, if they had a broadband Universal Fiber Network in this country. But that is yet another Commission failure in the "vision thing." The Asians & perhaps the Europeans will "clean our clocks" on this failure alone.
So, sayonara RF spectrum, my dear elderly love! I will always keep in mind you as you were in those long-ago days when you were still young, fresh, & exquisite.
LBA is your source for RF interference & RF shielding solutions.
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