They can, if they are certain that they are documenting BPL and not another
source. It is possible to misidentify other sources as BPL, so having a
time-domain and frequency-domain analysis of the received signal will be an
important cross check.

73,
Ed Hare, W1RFI


Good point. Ed, what does a plasma TV look like compared to BPL. Is the
multidomain signature quite different?

73,
Chip N1IR

Good point. Ed, what does a plasma TV look like compared to BPL. Is the
multidomain signature quite different?

I have not looked at a plasma TV, Chip, but I would make that diagnosis
primarily on on the basis of the sphere of influence. In the BPL test areas,
the interference was heard over the entire area that had the BPL couplers in
place.

There are other indicators, too. Knowing the involved BPL manufacturer would
let one pretty easily compare what was heard on the air to the known
characteristics of the BPL system involved. Interference from plasma TVs is not
going to be "modulated" with digital signals, as would a BPL signal. Those
OFDM carriers in the Ambient and Amperion BPL systems would be pretty hard to
confuse with anything else.

Another characteristic to look for is spectral occupancy. If the signal appears
suddenly in spectrum, is heard over several MHz, then suddenly tapers off, that
also matches the BPL characteristics, not that from other devices.

If the signal is noiselike, but clearly digital in sound, one can also look for
the bursts of the downloads, followed by the shorter, "keep alive" pulses that
some of the systems do.

If all of the above added up and started at the same time the BPL system was
brought on line, I would feel comfortable with my diagnosis.

73,
Ed Hare, W1RF

Ed...

Is the ARRL preparing a FAQ for amateurs who have scopes, spectrum
analyzers, or service monitors, etc., as to how they might go about
inspecting a suspected chunk of spectrum and how detect, identify,
qualify whey they see/hear?

73
Dan (K0DAN)

I have not looked at a plasma TV, Chip, but I would make that diagnosis
primarily on on the basis of the sphere of influence. In the BPL test areas,
the interference was heard over the entire area that had the BPL couplers in
place.

There are other indicators, too. Knowing the involved BPL manufacturer would
let one pretty easily compare what was heard on the air to the known
characteristics of the BPL system involved. Interference from plasma TVs is not
going to be "modulated" with digital signals, as would a BPL signal. Those
OFDM carriers in the Ambient and Amperion BPL systems would be pretty hard to
confuse with anything else.

Another characteristic to look for is spectral occupancy. If the signal appears
suddenly in spectrum, is heard over several MHz, then suddenly tapers off, that
also matches the BPL characteristics, not that from other devices.

If the signal is noiselike, but clearly digital in sound, one can also look for
the bursts of the downloads, followed by the shorter, "keep alive" pulses that
some of the systems do.

If all of the above added up and started at the same time the BPL system was
brought on line, I would feel comfortable with my diagnosis.

73,
Ed Hare, W1RF

Is the ARRL preparing a FAQ for amateurs who have scopes, spectrum
analyzers, or service monitors, etc., as to how they might go about
inspecting a suspected chunk of spectrum and how detect, identify,
qualify whey they see/hear?

Not at this time, Dan. I want to talk with amateurs who are going to go into
the trial areas, to share my experiences and to make sure I learn as much as
possible from theirs. FAQs are a great way for beginners to learn about a
subject, but some things are still best left to real dialogue.

73,
Ed Hare, W1RFI

On 17 Oct 2003 11:15:24 GMT, (W1RFI) sent into the
ether:

Is the ARRL preparing a FAQ for amateurs who have scopes, spectrum
analyzers, or service monitors, etc., as to how they might go about
inspecting a suspected chunk of spectrum and how detect, identify,
qualify whey they see/hear?

Not at this time, Dan. I want to talk with amateurs who are going to go into
the trial areas, to share my experiences and to make sure I learn as much as
possible from theirs. FAQs are a great way for beginners to learn about a
subject, but some things are still best left to real dialogue.

73,
Ed Hare, W1RFI


Hi Ed, good work. I probably missed it, but will ask anyway, is there
a list of the areas that are being tested? Anything in the Northern
IL or Southern WI areas?

Dan, N9JBF
Dan, N9JBF
Amateur radio - What a hobby!
Remove left x for direct reply

I probably missed it, but will ask anyway, is there
a list of the areas that are being tested? Anything in the Northern
IL or Southern WI areas?

Nothing in those areas, at least not for now. I have most of the locations
pinned down, but I have not posted them on a "public" URL. A few of the
utilities and one of the BPL manufacturers (Ambient) is being very cooperative.
One of the promises I made is that ARRL will help them determine the
interference potential of BPL systems, but that we will do it in a way that is
minimally disruptive to them. Having hordes of hams showing up in these areas
would probably not be a good idea, especially seeing as it would only take one
of the ones who offered to use the couplers for target practice to undermine
months of building good will.

If you are willing to do a more quiet foray into the test areas, email me and
let me know and I can provide some info, although it will be a good drive for
you.

I have posted the cities involved, and can repeat the list if it is needed.

73,
Ed Hare, W1RFI

Having hordes of hams showing up in these areas
would probably not be a good idea, especially seeing as it would only take
one
of the ones who offered to use the couplers for target practice to
undermine
months of building good will.

Defnintely not fair play!

If you are willing to do a more quiet foray into the test areas, email me
and
let me know and I can provide some info, although it will be a good drive
for
you.

I have posted the cities involved, and can repeat the list if it is
needed.

I can do a quiet sniff within any reasonable distance of east central
indiana.

BTW: I was wondering exactly how you calibrate your system for field
strength values.

On 18 Oct 2003 20:32:45 GMT, (W1RFI) sent into the
ether:

I probably missed it, but will ask anyway, is there
a list of the areas that are being tested? Anything in the Northern
IL or Southern WI areas?

Nothing in those areas, at least not for now. I have most of the locations
pinned down, but I have not posted them on a "public" URL. A few of the
utilities and one of the BPL manufacturers (Ambient) is being very cooperative.
One of the promises I made is that ARRL will help them determine the
interference potential of BPL systems, but that we will do it in a way that is
minimally disruptive to them. Having hordes of hams showing up in these areas
would probably not be a good idea, especially seeing as it would only take one
of the ones who offered to use the couplers for target practice to undermine
months of building good will.

If you are willing to do a more quiet foray into the test areas, email me and
let me know and I can provide some info, although it will be a good drive for
you.

I have posted the cities involved, and can repeat the list if it is needed.

73,
Ed Hare, W1RFI


I was just curious about the locations. I would be interested in
helping in my area, Mid to Southern WI or Northern IL. If anything
happens out this way, let me know if you need a hand.
Dan, N9JBF
Amateur radio - What a hobby!
Remove left x for direct reply

Has a radio station lost income because advertisers
are not having their messages heard by some listeners?
Have any radio stations complained of interference
of any sort ?

These people count much more than anybody because
they have money which means influence.
What would really count is to vote out the present
government so that it would cost twice as much as
was originaly thought as influence costs would
have to start all over again.
On the other hand is local broadcasting on the way out
together with ham radio? We appear to know everything that counts
so that with mystery gone so will curiousity. Our monthly magazine
is not eagerly awaited anymore as the first portion is really of
interest to the few and the second portion is devoted to
organisational business.
Seems like a lot of hams have migrated to the internet to discuss
items of interest.
You certainly do not hear technical discussions anymore
I personaly have not been on the air for ages
other than an occasional test, and I suspect that I am not alone.
Maybe it is time to move on and give up the frequencies anyway.
Do enjoy my RADCOM tho because it talks to me, not down to me
as someone who should get an education and rise up to the
publishers level. Frankly our membership and influence is dwindling
fast,
so maybe we would regain it back if we let this scheme go ahead so we
can
say ' we told you so ' rather than howling into the wind.
Since most things are now discussed on the internet rather than ham
radio
perhaps we should think more of what is best to the common interest,
perpetuating ham radio for the few old people until they die or
enlarging internet access for the many and for the future, something
that our hobby does not have.
Art

Please throw your rocks into this basket and not at me !
TIA


i i
i i
i i
i______1
x

Good point. Ed, what does a plasma TV look like compared to BPL. Is the
multidomain signature quite different?

I have not looked at a plasma TV, Chip, but I would make that diagnosis
primarily on on the basis of the sphere of influence. In the BPL test areas,
the interference was heard over the entire area that had the BPL couplers in
place.

There are other indicators, too. Knowing the involved BPL manufacturer would
let one pretty easily compare what was heard on the air to the known
characteristics of the BPL system involved. Interference from plasma TVs is
not
going to be "modulated" with digital signals, as would a BPL signal. Those
OFDM carriers in the Ambient and Amperion BPL systems would be pretty hard to
confuse with anything else.

Another characteristic to look for is spectral occupancy. If the signal
appears
suddenly in spectrum, is heard over several MHz, then suddenly tapers off,
that
also matches the BPL characteristics, not that from other devices.

If the signal is noiselike, but clearly digital in sound, one can also look
for
the bursts of the downloads, followed by the shorter, "keep alive" pulses
that
some of the systems do.

If all of the above added up and started at the same time the BPL system was
brought on line, I would feel comfortable with my diagnosis.

73,
Ed Hare, W1RF


Hi Ed,

I think a general description of other RFI sources would be helpful for any
radio amateur to make a 'first cut' assessment. It might also help you isolate
the truly legitimate cases of BPL RFI--if and when they exist.

I do have a concern that hams not make too many false alarms. Sounds like you
are on top of the the problem and I wish you the best.

73,
Chip N1IR