Ask old curmudgeon from RF – "What about RF interference from LED devices?"

As for observing your LED transmitter, I only have a UHF two-way radio in my car, so I have not noticed the “LED effect” on the high VHF band. We have a lot of LED traffic lights in my area so part of the equation is in place. And don’t forget about all those red LEDs in car taillights now. I have also not noticed anything from the LEDs directly on FM broadcast channels, including IBOC stations, but that’s more of a reflection that we have such strong broadcast signals in my area of ​​the country.

In response to your other observation, yes, the FCC doesn’t give a damn about the RF spectrum or its purity. I believe that this trend started more than a decade ago and is driven by two deeply ingrained political positions in the Commission. First, they desperately want to get out of the enforcement business. They don’t get any major points or funding from Congress to run the Office of Field Enforcement (or whatever it’s called now), spectrum enforcement is a bottomless pit for them and it’s a never-ending task. They would rather auction off the spectrum and tell the happy buyer, “Take care of * your * bands clean! We’re getting out of here!”

The second is the deeply ingrained regulatory notion that “cellular transmission” with its concurrent frequency reuse is the highest and best use of spectrum. If you use a cell phone, you don’t have to worry too much about the ambient noise level, since the transmitters are always quite close to the users. The cellular regulatory model is at work not only in public land mobile telephony, but also in private land mobile telephony (where it is very difficult to obtain new PLMRS licenses for the top of a wide area mountain or major tower stations, and if You get one on most stations then you can run your “walkie talkie” power levels. And on broadcasting (LPFM and LPTV, which also conveniently use all available channel slots). And on Party’s license-free wireless LANs. 15. “Etcetera, etcetera, etcetera,” as the king of Siam would say.

I don’t know if it detected it at the time, but a few years ago the Commission released an NPRM that proposed * allowing * interference sources on licensed channels (in this case, microwaves), using a concept known as the defined “Interference Temperature! ” The idea was that the “smart radios” at the source of the jammer would “know” when the source had gone a bridge too far and then it would turn off. Lacking that degree of equipment capability from interferers, the channel licensee would always be able to monitor and shout when the measured “interference temperature” exceeds set limits.

The industry quickly shot down that * ^ @ (& ^ idea!

So, driven by these two philosophical points, the Commission now says: “Please proceed to destroy the spectrum with many unlicensed low-power devices, singing power lines, screeching power meters, high-speed digital logic with times of femtosecond switching (exaggerating, but not by much!), screeching LEDs. We don’t care, and we’re no longer enforcing the law here in Dodge City! “

As soon as some smart businessman discovers a use for the 4 Kelvin cosmic microwave background radiation, it too will be quickly licensed and eventually auctioned.

You and I, who are veterans in this art and science, understand the invaluable resource that the RF spectrum represents, we respect it, and we do what we can to keep it in good working order. The Commission, especially in later years, has been directed and directed by lawyers, economists and politicians who do not know the physics behind electromagnetic transmission, they have no “vision” for the future non-economic uses for which the silent spectrum could use and consider the spectrum primarily as an exploitable economic good. What did you expect?

In addition to this outrage, today there is too much transfer of communications from wired to wireless modes. Most people don’t really need a “navel web service”. Now my eleven-year-old granddaughters have their own cell phones. Give me a (& #% $ @ & break!

Many, many services could be provided well and cheaply over cable, if only we had a broadband Universal Fiber Network in this country. But that is another failure of the Commission in the “matter of vision.” Asians and perhaps Europeans will “clean our clocks” just with this failure.

So sayonara RF spectrum, my dear old love! I will always remember you as you were in those days, when you were still young, fresh and beautiful.

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