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L.A. Building's Lights Interfere With Cellular Network, FCC Says
alphadogg writes "When a certain Los Angeles office building lights up, it's a dark day for nearby cellphone users, according to the Federal Communications Commission. Fluorescent lights at Ernst & Young Plaza, a 41-story tower near the heart of downtown, emit frequencies that interfere with the Verizon Wireless 700MHz network, the agency said in a citation issued against the building owner. The FCC's message comes through loud and clear in the filing: the building owner could be fined up to $16,000 a day if it keeps using the interfering lights, up to a total of $112,500. The alleged violation could also lead to 'criminal sanctions, including imprisonment,' the citation says."
Isn't this a case where the manufacturer of the fluorescent fixtures needs to fix them so they don't emit interference? Don't electronics of that type have to go through FCC testing?
Who are they planning to imprison for this? The president of the company? The guy who changes out the lightbulbs? Will they build a giant prison around the building?
Neither Ernst nor Young are around to throw in the slammer, both having started their corps. in the early 1900s.
What ever happened to the ubiqitous 47 C.F.R. 15.5? How did this building even find noncompliant lights to install, in the US? And weirder still, why the hell would a lighting system use 700MHz?
As the decriminalization of marijuana continues along it's mary way, there will develop a need to fill prison beds.
Happiness in intelligent people is the rarest thing I know.
Ernest Hemingway
Measurements will reveal that the emitted frequency is actually 666 MHz, pointing to a less divine source. ;-)
The Tao of math: The numbers you can count are not the real numbers.
Why not something more specific.
comp.misc.slashdot perhaps?
You clearly don't know Usenet rules. A more specific group for comp.misc would be comp.slashdot. Which could then be split up into comp.slashdot.developers, comp.slashdot.ask, etc. with comp.slashdot.misc for the stuff that doesn't go into one of the more specific groups.
However given the group creation rules (assuming they are still enforced), it would be easier to create alt.slashdot instead of comp.slashdot (alt.ALL is a hierarchy with much more relaxed group creation rules).
The Tao of math: The numbers you can count are not the real numbers.
As Verizon (especially) lights up LTE they bring in trucks that look for problems in the 700MHz bands. They are taking a proactive approach to cleaning up the band before RFI causes problems. This makes sense since LTE uses QAM and high symbol rates to push data, meaning that the carrier to noise requirements are much higher than 3G. Most cable companies use the same frequency band, up to 750MHz. To make matters worse, cable systems use QAM carriers too, so the demodulators can get confused and pick up the wrong carrier.
Cable companies monitor their plant for signal egress from broken coax, cracked housings, poor craftsmanship, etc (leakage), but usually around 115MHz, in the aeronautical bands (since there's been cases of planes lining up on leaks instead of the glide path). Because some types of leaks are frequency dependent, a system that looks great in the aeronautical band might leak like a sieve at 700MHz. In fact a certain set top box happened to have vent slots that made a perfect antenna at 700MHz.
http://www.slideshare.net/Cisc...
"Well, good luck finding a judge that doesn't run a bestiality site."
Most LEDs I've seen are a little more efficient fluorescent bulbs, plus they last a lot longer.
Two things: CFLs are less efficient than standard linear. light fluorescents. Second, commercial CFLs and fluorescents last a lot longer than cheapie ones you might get from most stores: tubes exist for ratings up to 30k hours.
Thirdly...
Our three main points are: 1) linear tubes, 2) longer life and 3) don't forget to compare modern tubes on modern ballasts and starters. And an almost fanatical devotion to the pope.
Our points include: 1)...
SJW n. One who posts facts.
It doesn't matter what GE does if the building keeps the old fixtures in use.
The building management was notified of the problem last April by the FCC. The management claimed they knew about the problem and were investigating. They agreed to send a report of the problem and remediation plan in 60 days. At that time, no fines were contemplated. Here we are 10 months later and no report and no remediation. Given that, the FCC has no reason to believe they'll ever do anything about it without significant prodding.
Back in April, they had plenty of time to contact GE and insist on replacements and compensation for the cost of swapping them out. Had they done it then, they could have avoided major disruptions.
After a bunch of anecdotal reports we did some measurements of radio interference caused by LED lighting (and the power supplies included in these globes).
Most were OK, but there are a bunch that spray out a large amount of broad band interference. Some spectrum graphs are here showing a few lights in their on and off states.
http://www.ledbenchmark.com/fa...
Interference was seen in the digital radio bands, FM radio, DAB bands, everywhere really. So the only thing surprising about this post is the lack of publicity the problem has been given to date.