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A lawsuit from a widow whose partner died as a result of the EMS being unable to properly dispatch its personnel in a BPL-enabled community.
Any company who operates a voice service prepares power backup and generation primarily for liability. They could care less if your phone service goes out because of a power failure - they only wish to limit their liability should you not be able to call 911.
Jeepster's right, the FCC should step in and do their jobs. Almost every electronic device I buy has the following:
"This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received, including interference that may cause undesired operation."
Why the FCC hasn't stepped in here and produced a set of maximum interference specifications is beyond me.
- Sherman |
XJMark
join:2004-01-10
Seminole, FL
2 edits | --snip--
Jeepster's right, the FCC should step in and do their jobs. Almost every electronic device I buy has the following:
"This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received, including interference that may cause undesired operation."
--snip--
The following paragraph pretty much sums it up, and is what I expected, (quoted from the ARRL story)»www.arrl.org/news/features/2004/···/1/?nc=1
"It's too soon to draw many firm conclusions from this one test observation. Amperion's tests show that their signals meet Part 15 guidelines, although those guidelines were drawn more to measure the leakage from a computer cabinet than from a long unshielded wire. Amateur observation of this and other BPL trials show that, Part 15 limits notwithstanding, the radiation is clearly enough to cause harmful interference in the immediate vicinity of the power line, which would violate Part 15, whether the signal is within radiation limits or not."
Of particular interest is the following statement: "Amperion's tests show that their signals meet Part 15 guidelines, although those guidelines were drawn more to measure the leakage from a computer cabinet than from a long unshielded wire."
As I suspected, the device was tested for type acceptance as just that, a stand-alone device most likely an unintentional radiator. BPL is a "system" and not a stand-alone device. While one piece of the system may exhibit field strength within limits for an unintentional radiator in a laboratory, out in the real world connected to its infrastructure it is clear that it is operating outside of Part 15 limitations.
Of course, while there is no way to fit the transmission lines, power pole transformers, and household wiring of an entire town into an RF lab or anechoic chamber it was clearly not taken into consideration. These infrastructure components make up the entire system and they all become intentional radiators because powerlines are of sufficient length to resonate at those wavelengths.
Part 15 clearly defines intentional and unintentional radiators:
47 CFR 15.3(z) and 15.3(o) describe unintentional and intentional radiators.
15.3(z)
Unintentional radiator. A device that intentionally generates radio frequency energy for use within the device, or that sends radio frequency signals by conduction to associated equipment via connecting
wiring, but which is not intended to emit RF energy by radiation or induction.
15.3(o)
Intentional radiator. A device that intentionally generates and emits radio frequency energy by radiation or induction.
Another interesting point is found in the FCC's own Notice of Inquiry text for ET Docket No. 03-104 Released April 28, 2003.
"8. In addition, the existing Part 15 rules do not provide a clear procedure for measuring emissions from carrier current systems. On May 29, 1998, the Commission adopted a Notice of Inquiry in ET Docket No. 98-80 to examine its Part 15 line conducted emission limits. As part of that proceeding, the Commission requested comments on its existing Part 15 carrier current requirements and measurement issues. The Report and Order in that proceeding harmonized the Part 15 requirements for conducted emission limits with the international standards developed by the International Electrotechnical Commission (IEC), International Special Committee on Radio Interference (CISPR). However, because of the ongoing development of systems using new BPL technology, the Commission also decided in that Report and Order to defer the consideration of carrier current systems and BPL system issues to a separate proceeding."
Interesting, The FCC concedes that "the existing Part 15 rules do not provide a clear procedure for measuring emissions from carrier current systems." That would explain why this BPL nonsense was type accepted to part 15 as stand-alone devices in the first place. Since there's no way to type accept the infrastructure of an entire town you type accept what you can (the individual unintentional radiators) and just deny the rest as just figment of imagination as the BPL lobby has been doing.
The FCC is ultimately responsible for this mess by allowing the type acceptance of these devices knowing full well that a set procedure for measuring carrier current emissions didn't exist.
Part 15 regs. can be found here: »www.access.gpo.gov/nara/cfr/wais···_02.html |
