"Fractenna" wrote in message
...
BPL comes into your house at the power company service box. Even if you
don not connect to it.


FACT: The Cedar Rapids deployment has a WLAN link from the pole. The
wires
carry the 2-80 MHz. How does that go from 2-80 MHz --into-- the house?

It is true that at least one (proprietary - they're all proprietary)
implementation of BPL forgoes the issues associated with coupling around the
transformer that steps the MV distribution down to 220 VAC for the feed to
the house by using 802.11b to link from a distribution point (essentially an
802.11b access point) to the computers in nearby houses.

However ...

It creates S9++ signals from 2 to 80 MHz.

Even the "flavor" that uses 802.11b to get from the pole to your house
radiates a LOT of interference in the HF/low VHF bands it uses from the
(nearby) distribution lines.

The "main.net" system operated by PP&L in Emmaus, PA measured -60 dBm
(that's S9+13 dB) of interference in a 3 kHz bandwidth, using an "Outbacker
Joey" short whip clamped to the roof rack of my Ford Explorer.

That rendered 20m SSB signals in the range of -80 to -100 dBm (which would
normally be quite usable) unintelligible.

FACT: Sure, if you drive your 1972 Nova with 'HAM ON BOARD' sticker (for
example) under the power line, this is a consistently true statement.
Otherwise, there are some, few, circumstances in which an unacceptabel
(pun
and sic intended) level of 'hash' will arise in that passband to the
annoyance
of some hams. Based on assumption, the number of hams affected nation wide
is
in the hundreds.

I'm not sure where you come up with the assertion that the number of hams
affected is "in the hundreds."

Are you referring to the number affected by the current, very limited "trial
area" deployments of BPL? If so, the numbers are probably relatively small.
HOWEVER, if BPL is deployed more or less ubiquitously, there will be few
hams far enough from a power line to not be SERIOUSLY affected.

For comparison, the number of hams affected by tower erection restrictions
is in the tens of thousands.

True, and that's a valid crusade as well, but how does the existence of that
problem imply that we should ignore the problem of BPL?
(Remember, BPL will not affect just those who want to/can afford to erect
towers, but ALL hams that use HF/6m ... even with simple dipoles or
verticals.)

You can't hear anything on your new 10,000 dollar ICOM 7800 or any other
radio except 'Data Hash'.


FACT: Sure, if very nearby and unfiltered, this could be a problem.
However,
the FCC rules require filtering for RFI mitigation in such circumstances.

Right now, the FCC rules don't require squat other than for the Part 15
device (in this case the BPL system) to shut down unless/until interference
can be eliminated. The radiated emission limits for BPL are WAY too high.
The "mitigation techniques" that the FCC and the BPL folks pay lip service
to are not in place, nor is it at all clear that they will be effective,
even if the power companies are responsive (and we've seen how responsive
most of them are [not]).

Is that clear enough??

Is that clear enough???

FACT: A vocal minority of hams want to 'kill BPL'. As opposed to working
with
the power companies to fix the problem.

I don't see it as a "vocal minority" ... all of the hams I know are
concerned that BPL will trash the HF bands and that the FCC and the power
companies will do little/nothing about it (the FCC hasn't acted on
complaints thusfar ... they've been buried in OET rather than being dealt
with in accordance with the existing rules.)

If someone could show me a technically sound way that BPL could use the HF
spectrum without trashing us, I'd have no problem with it. The problem is
that, as it is, it *does* trash us in any area where it's deployed and there
is no solution in sight.

There is one BPL technology - from a company called "Corridor" - that
appears to avoid the problem by not using the HF/low VHF bands ...

FACT: The press has used this exchange, in many circumstances, to view us
with
the jaundiced eye of being anti-technology and very out of date. Why is it
that
they just don't see it as reason to 'kill BPL'?

"The press" feeds on controversy and frequently distorts things - at best in
the interest of making the story more "sensational, at the worst because
they have taken sides and have their own agenda to promote rather than
objectively and dispassionately reporting the facts.

Carl - wk3c