I also encourage everyone to send a donation to the ARRL's BPL fund - you
don't have to agree with *everything* the ARRL does to be willing to help
to overcome this major threat to our future on HF.

I don't agree with everything the ARRL does either, Carl, so we are even on
that score. I have seen ARRL board motions pass 8:7, so in that case, 7 members
of the ARRL board didn't agree, either.

Every year or two, I look at the big picture and decide to keep going. The
League's work on BPL this year has justified my 12 cents a day every single day
that I know of!

73,
Ed Hare, W1RFI

In article , Carl R. Stevenson
wrote:


Hi Carl,

I made a trip to the Cape Giradeu MO test area. This ws a very limited
test area encompassing maybe 10 - 15 homes judging from the inductors I
saw on the utility poles. I found that BPL seems to operate in an
"idle" mode and a active demand mode.

When in the idle mode the intereference from the upper BC band through
20 meters is quite noticable and was registering S7 - S9 on the meter
of my IC-737 connected to a Hustler antenna with 40 and 20 meter
resonators attached. It was also audible from about 1520 and up on the
BC band.

When in active mode, (probably when someone was downloading something)
the S meter readings went to 30+ over S9 and the top of the broadcast
band was seriously hacked up. I also detected effects at the bottem of
the FM broadcast band. The highest reading I saw was on the 20 meter
band. When in the active mode, I could detect serious levels of BPL
interference at 500 feet growing weaker out to about 1,000 feet when
it dropped below my traditional mobile noise level.

After hearing it and seeing it's potential for devestating interference,
I am of the opinion that it will be a serious problem for anyone using
the spectrum between 1.6 and 88 MHZ. In addition, I am willing to bet
that the radiation will be rich in harmonics.

73
George
K3UD

EX- WA3DNC, W3GEO

"W1RFI" wrote in message
...
Write or call your local AM broadcast stations and tell them that
thier signal is being wiped out and you can't recieve them.

When I was in Emmaus, PA, I turned on the car AM radio and didn't hear any
noise on the AM broadcast band. I believe that some of the reports may
have
been in error.

73,
Ed Hare, W1RFI

I can confirm what Ed reports above ... on my first drive through the Emmaus
BPL area, I didn't have my FT-817 with me ... I noted little/no BPL noise
in the AM broadcast band ... perhaps a bit of extra noise at the very upper
end of the band around 1600 kHz, but nothing like what exists on 80-15m.

Again, I want to help Ed drive the point home - false claims of "BPL
interference"
will do a LOT of harm to our cause ... I encourage anyone who thinks they
might
be experiencing BPL interference to communicate with Ed and let him help to
verify
things.

I also encourage everyone to send a donation to the ARRL's BPL fund - you
don't have to agree with *everything* the ARRL does to be willing to help
to overcome this major threat to our future on HF.

Carl - wk3c

"PDQ" wrote in message
...
In article , Carl R. Stevenson
wrote:


Hi Carl,

I made a trip to the Cape Giradeu MO test area. This ws a very limited
test area encompassing maybe 10 - 15 homes judging from the inductors I
saw on the utility poles. I found that BPL seems to operate in an
"idle" mode and a active demand mode.

You might want to contact this fellow.

http://iamnee.com/

I don't remember if he's a ham, I worked with him on a project there a
couple years ago. He does have nice spectrum analysis tools, and he lives
there in Cape G.

Ed, is there a URL where we can view the location of all the test sites
now in use? How about future planned test sites?

Email me privately. I have put one together, but it has a lot of Mapquest maps
that are copyrighted, so I am not posting it. It is essentially for the "fair
use" of HQ staff and those working on the BPL issues in the field.

73,
Ed Hare, W1RFI

Proximity to the power grid would be the main clincher, IMO, but what
about skywave propagation? That stuff could go around the world at QRP
levels!

No single signal will be heard by skywave; the power levels are too low.

Here's the math:

Power level: -50 dBm/Hz
Corrected to 3000 Hz: add 35 dB
Coupler loss: -10 dB
Powerline antenna gain: -10 dB
Path loss VOACAP: -110 dB

That gives a received signal level of -145 dBm/3 kHz, well below the ambient
noise at any HF station.

And millions of them may not make as much difference as we might think. They
way these systems work, they share bandwidth between many users, so the signals
are time muliplexed, so only one signal on a particular power line is active at
a time. 100 shared signals have the same peak field strength as 1 signal, for
the most part. So there may be 10,000 simultaneous emitters in a metro area.
That will add 40 dB, bringing it just above the band noise -- interesting, but
not conclusive.

The problem is local, and our concerns should be focused there.

73,
Ed Hare, W1RFI