Re: another major BPL deployment

[nobody@xxxxxxxxxxxx (Dave Houston)]

Wow! I found an extensive quote from a real ARRL expert that seems to
contradict much of what you are saying. It's from...

http://www.eham.net/articles/12322

and I'll provide the entire quote. Otherwise, you might be tempted to
mischaracterize it. ;)

<quote>
RE: New ARRL Petition Seeks to Resolve BPL Standof     	 Reply
by W1RFI on October 24, 2005 	Mail this to a friend!
> Interesting. So, where's the data from Ed Hare's
> exhaustive testing to show that the two products do
> not cause any interference to any amateur bands?

You are right, Lee; you are confused. From a regulatory perspective, the
goal is NOT to set limits and conditions that would make interference
impossible. You would not want those limits placed on Amateur operation,
would you? To unconditionally protect Grade B TV service would require 110
dB of harmonic supression, IIRC. If Amateur Radio were being proposed and TV
broadcasters asked the FCC for regulations that were stringent enough to
make interfernce impossible, none would think them reasonable.

Remember, this is a petition for rulemaking that is intended to set
reasonable rules under which BPL can function, but without widespread
harmful interference. Just like the rules that apply to our stations, in
which limits are set that will limit our harmonics to a degree, then depend
on the "no interference" clauses in the rules to require some of us to add
low-pass filters when needed.

Good regulations have balance, and a supportable regulatory goal is to have
restrictions that will reduce the number of interference problems to a small
enough number that is practical to handle them on a case-by-case basis, thus
allowing the rules about harmful interference to have a chance at working.

> ARRL was quick to criticize, based on data. Now, its > sufficient to say the Current Technologies'
> configuration is FB?

"Sufficient to say?" Do you really believe that all ARRL has done is to just
say so? C'mon, Lee. That sounds good echoing from your soapbox, but I have
personally put three years into studying and analyzing BPL, and ARRL would
not take these steps unless there were good reasons for them. However,
seeing as you presume deception or incompetence unless you are personally
given the background, let me provide you with some of it. (Most people would
be sure that they had justification before jumping on a public forum and
cricitizing, btw...)

Current Technologies systems use HomePlug technology. (See
http://www.arrl.org/~ehare/rfi/HomePlug/HomePlug_ARRL.pdf). The HomePlug
modems operate between 4 and 20 MHz, with the amateur bands notched. They
operate only from 120/240 volt wiring, thus have a much smaller geographical
footprint than overhead power lines. They are dead quiet except when in
acutal use. Their ham band notches are about 25 dB lower than the present
FCC limits and, in most cases, house wiring appears to radiate somewhat less
than the FCC's limits, from all I have seen.

When you combine these, a simple calculation (you did all those simple
calculations before you wrote your post with all the "news for ARRL", didn't
you, Lee?) shows that this level should be enough to protect mobile amateur
operation.