>BTW, I am curious why nobody has tried exploiting the MMDS band
>(2.5 to 2.7 GHz) for broadband service. Fixed costs are probably
Sprint tried offering fixed wireless service using a proprietary
protocol in the SF Bay Area a few years ago. The service was great, but
they could not make money on it at $50/mo, and discontinued the
service. The service was in a band near 2.4 Ghz, not 802.11b, for which
Sprint had a primary allocation. You had to be LOS to one of two
mountains. My boss had a pizza box antenna way up on a 20 ft pole. He
did suffer some attenuation from rain and fog, but said the service was
great - this was back in 1999 or 2000.
Some ISPs are offering 802.11b based service. A college friend runs a
successful ISP out of Hamilton, Texas, and covers a 10,000 sq mi area
with 802.11b service. He can get 10 mile links without an amp and 20
miles with an amp, and says it works well. (up to 4W EIRP is legal Part
15, that's 1W with 1 6db antenna or equiv.)
>> i think our power meters are read using some kind of rf over
powerline,
>> but is seems to me it is on uhf or higher.
These systems run at VLF frequencies. I think I get them on HF from my
power line - every once in a while during the day I pick up a noise off
the power line that sounds like a rotary telephone dialing, except it's
radiated at HF. I've DFed it to the power line and it's not a telephone
signal. It doesn't happen all the time, and it's not the X-10/BSR
remote control devices as far as I know because I have them and they do
not cause interference (they use a very low, almost audio-freqency
carrier.)
By the way, PG&E is finally doing something about the arcing pole
across the street from me. It took a 60-day wait and a certified
letter. but Tuesday a lineman came out and poked at the crossarm with
his hot stick, and big time interference ensued, along with the
crossarm nearly falling off. (our lights have been flickering at home
for a couple weeks, too.) I feel sorry for the line guys - it's
management that held my case back, because it wasn't dispatched to the
lineman's supervisor until Monday.
-Wiley KF6IIU
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