"Dick Carroll" wrote in message
...
Carl R. Stevenson wrote:

"Dick Carroll" wrote in message
...

[snip]

You raise an interesting question, Carl. How exactly should the
average ham go about proving that the RFI is indeed BPL, when the BPL
people say
"That's not us!'??



BPL has a unique "signature" (in the spectral/time domains) that can be
used to ID it.

Since there are different systems (SS from main.net and OFDM from
Amperion,
for example) they have different signatures, which are distinct from
other
sources
of interference and more traditional power line noise (of course the
utilities are
responsible for fixing the latter, too ... though their record is poor).


So to repeat, how does the average ham, whom you have exhorted to
"make sure it's BPL that you're complaining about", go about detecting
and sorting which is what, given that spectral analysis gear, and the
training to use it if it was available, is virtually nonexistnt in the
average hamshack? Is there a aural signature or more than one for the
different BPL modes? Is the Emmaus test site video/audio clip
reresentative enough to make the call, or is something more needed?

The Emmaus test site video (test area #3) should be pretty representative
of the "main.net" system ... test area #4 is the Amperion OFDM system.
There could be others that might have different "signatures" ...


I expect that if it was indeed BPL RFI it would follow the power grid
pretty closely with signal strength highest when close, and tapering off
with distance away from the lines. But from the one report posted here
of a ham who said he heard it from a distance of 60 miles, seems like
propagation will play into the picture-to be expected at HF as all
experienced HF ham operators know. Or maybe *he* mis-identified it!

I suspect that may be the case ... though it's not impossible that under
ideal conditions of terrain, propagation, with good antenna, etc. that
it *might* be detectable at some distance ... whether current levels of
deployment would cause truly "harmful interference" at such a distance
requires further study.

So who do hams call for assistance, the ARRL? I haven't seen anything
from them suggesting that.

My recommendation would be to e-mail a .wav file or other common
audio file format to Ed Hare, , and give him the particulars
of time, location, if you *know* that your utility is doing a BPL trial,
etc.
(I'd appreciate a cc: of the audio file and particulars to my main e-mail
address as well, just for my own information and
analysis.)

The MAIN thing is to NOT have a bunch of false "BPL interference
complaints."
The BPL industry is trying to paint the ARS as "exaggerating the potential
for
interference" and doing a lot of hand-waving ... inaccurate claims of "BPL
interference" at this point will do more harm than good.

Carl -wk3c