Dave Shrader wrote in message .net...
The ARRL site, http://www.arrl.org/tis/info/HTML/plc/#Field , provides
links to the following information:
"PLC is a "carrier-current" system, designed to intentionally conduct
signals using electrical wiring. Although a carrier-current device is an
unintentional emitter, because the power lines have such a significant
potential to radiate and because a practical carrier-current device
generally needs more signal than the permitted conducted emissions
levels for unintentional emitters, carrier-current devices are not
required to meet those conducted-emissions limits, but are required to
meet the general radiated emissions limits in Sec. 15.209.
§ 15.209 states that the radiated emission limits of intentional
radiators generally can't exceed the field strength levels specified in
the following table:
Frequency (MHz) Field Strength (microvolts/meter @meters)
0.009-0.490 2400/F(kHz) 300
0.490-1.705 24000/F(kHz) 30
1.705-30.0 30 30
30-88 100 3
88-216 150 3
216-960 200 3
Above 960 500 3
Carrier-current devices are "Verified" as described in the Part-15
rules. This means that the manufacturer is required to test them to
ensure that they comply with the FCC regulations. Under the present
rules, they must be tested at 3 typical locations. "
What's the FCC definition of "typical locations"??
Note that the HF Spectrum allows a S8 to S9 signal level, 30 uV/m at 30
meters distance.
15.209 is the problem, it's grossly outdated, did not foresee anything
like BPL and the limits needs to be revised downward which is one
piece of this brawl. Ref: Tailpipe emissions regs, same basic problem,
different pollution media.
Another piece of it is that the BPL crowd wants permission to bust the
already inadequate limits in 15.209. They're playing the regulatory
loopholes game. The Japanese jumped past their regulatory Catch-22
techo-babble and abolished BPL period. We need to follow the Japanese
lead and we're working on it.
w3rv
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