Military HF communications under attack

"phil hunt" wrote
Gene Storey wrote:
The FCC is full speed ahead with its BPL (Broadband over Powerline)
rule-making, and the U.S. Air Force is looking to spend billions now on
replacement communications systems, as the use of HF radio will no
longer be possible.

Why not?

Tune your radio to 60 Hz.

After BPL 2 mHz to 80 mHz (and their harmonics) will have trash on the
whole spectrum.

"Gene Storey" wrote:

"phil hunt" wrote
Gene Storey wrote:
The FCC is full speed ahead with its BPL (Broadband over Powerline)
rule-making, and the U.S. Air Force is looking to spend billions now on
replacement communications systems, as the use of HF radio will no
longer be possible.

Why not?

Tune your radio to 60 Hz.

After BPL 2 mHz to 80 mHz (and their harmonics) will have trash on the
whole spectrum.


C'mon Gene, try to make some sense here will you?...why should
one tune to 60 Hz? (the power line freq btw). Pls do explain what
the hell you're talking about.
--

-Gord.

"Gord Beaman" wrote

C'mon Gene, try to make some sense here will you?...why should
one tune to 60 Hz? (the power line freq btw). Pls do explain what
the hell you're talking about.

The power line frequency (after BPL) will include the frequencies
2 to 80 MHz and the harmonics. I was just using 60 Hz a poor example.

WWV time signals will be wiped-out. NDB navigation sites will be
wiped out. Etc, etc. The noise floor in the 2-60 MHz band will be
significantly higher than it is now, thus requiring higher power, or a
change in operating frequency.

"Gene Storey" wrote in message
...
"Gord Beaman" wrote

C'mon Gene, try to make some sense here will you?...why should
one tune to 60 Hz? (the power line freq btw). Pls do explain what
the hell you're talking about.

The power line frequency (after BPL) will include the frequencies
2 to 80 MHz and the harmonics. I was just using 60 Hz a poor example.

WWV time signals will be wiped-out. NDB navigation sites will be
wiped out. Etc, etc. The noise floor in the 2-60 MHz band will be
significantly higher than it is now, thus requiring higher power, or a
change in operating frequency.



Scottish Power are already running broadband over power lines,
this doesnt seem to have wiped out HF communication
and the authorities in the UK who jealously guard radio
frequencies seem not to be over worried.

Keith

"Keith Willshaw" wrote:


Scottish Power are already running broadband over power lines,
this doesnt seem to have wiped out HF communication
and the authorities in the UK who jealously guard radio
frequencies seem not to be over worried.

Keith


Hell...we already have roughly the same thing here in Canada and
the States (worldwide?).

Isn't ADSL really about the same?...(perhaps lower power
though)...they broadcast a ~one megaHertz RF carrier on
unshielded telephone cables...what's the difference really?...I
have this coming right into my 'radio room' where my (ham) HF
radio is located, I don't see any problem at all.
--

-Gord.

"Gord Beaman" ) writes:


Isn't ADSL really about the same?...(perhaps lower power
though)...they broadcast a ~one megaHertz RF carrier on
unshielded telephone cables...what's the difference really?...I
have this coming right into my 'radio room' where my (ham) HF
radio is located, I don't see any problem at all.

Telco cable is twisted pair; that's the difference....

[Twisted pair is in effect shielded cable, through the miracles
of 3-D integral calculus....]

--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

" wrote:

"Gene Storey" wrote:

"phil hunt" wrote
Gene Storey wrote:
The FCC is full speed ahead with its BPL (Broadband over Powerline)
rule-making, and the U.S. Air Force is looking to spend billions now on
replacement communications systems, as the use of HF radio will no
longer be possible.

Why not?

Tune your radio to 60 Hz.

After BPL 2 mHz to 80 mHz (and their harmonics) will have trash on the
whole spectrum.


C'mon Gene, try to make some sense here will you?...why should
one tune to 60 Hz? (the power line freq btw). Pls do explain what
the hell you're talking about.
--

-Gord.


I presume he is trying to make the, valid, point that all those power
lines radiate a very nice signal at 60Hz, and by implication that they
will do the same if BPL is permitted to transmit digital data between 2
and 80MHz over the same lines.

It's late, so I'm not going to try and look it up now, but IIRC BPL has
been banned in some administrations for precisely that reason - ISTR
that Japan is one such administration.

BTW John - Long (very long) wires make excellent antennas provided that
they are at least several wavelenghts long.

Dave

"Dave Holford" wrote in message
...


" wrote:

"Gene Storey" wrote:

"phil hunt" wrote
Gene Storey wrote:
The FCC is full speed ahead with its BPL (Broadband over Powerline)
rule-making, and the U.S. Air Force is looking to spend billions now
on
replacement communications systems, as the use of HF radio will no
longer be possible.

Why not?

Tune your radio to 60 Hz.

After BPL 2 mHz to 80 mHz (and their harmonics) will have trash on the
whole spectrum.


C'mon Gene, try to make some sense here will you?...why should
one tune to 60 Hz? (the power line freq btw). Pls do explain what
the hell you're talking about.
--

-Gord.


I presume he is trying to make the, valid, point that all those power
lines radiate a very nice signal at 60Hz, and by implication that they
will do the same if BPL is permitted to transmit digital data between 2
and 80MHz over the same lines.

It's late, so I'm not going to try and look it up now, but IIRC BPL has
been banned in some administrations for precisely that reason - ISTR
that Japan is one such administration.

BTW John - Long (very long) wires make excellent antennas provided that
they are at least several wavelenghts long.

Don't they tend to be directional off the pointy end?

"John Keeney" wrote

Don't they tend to be directional off the pointy end?

No. Electrical waves are right angles to the conductor, often shaped
like a doughnut. But it doesn't matter in the near-field, as the signal will be
everywhere.

Gene Storey wrote:

"John Keeney" wrote

Don't they tend to be directional off the pointy end?

No. Electrical waves are right angles to the conductor, often shaped
like a doughnut. But it doesn't matter in the near-field, as the signal will be
everywhere.


"LONG" wires, multiple wavelength antennas, exhibit gain in the
direction of the wire - bidirectional if not terminated, unidirectional
if terminated at the non-fed end.

You are thinking of the classic basic dipole.

Dave