Frank Dresser wrote:


"Gray Shockley" wrote in message
...
On Tue, 26 Aug 2003 23:17:45 -0500, Frank Dresser wrote
(in message
):

How's the 11 meter SW band for the hobby broadcasters? The
international broadcasters have pretty much abandonded it, the antennas
should be easy to work with and line of sight will work even when the
ionosphere doesn't.

Frank Dresser


Do you mean in place of CB, using CB freqs or ????

Thanks,



Gray Shockley


25.6 to 26.1 Mhz, just below the Citizen's Band. It's already set aside as
a SW broadcast band, although the broadcasters rarely use it.

Problem: most portables don't go that high. My DX396, for example, only
goes up to 21850 khz. Also, thewre's a lot of freebanders in that area,
apparently. 13m (starting around 21450) is barely used by major
stations, and would have similar propagation to 11m.

In rec.radio.amateur.policy CW wrote:
There are active military and government frequencies spread throughout the
HF bands, I have, sitting in front of me, two pages worth of active military
frequencies. This does not include FEMA, DEA, ect. Yes, they also use VHF
and satellite but maintain activity on HF for long distance as VHF is line
of sight and satellites are to vulnerable. You can do everything you want to
maintain your chicken little views but some of us know better.

As I have written, BPL devices *do* have the possibility to keep out
of *some* HF frequencies AFAIK. Ham radio would not be the first candidate
for this. Air mobile and military users would be more likely to benefit
from it.

And maybe it is a different perspective here in Austria, as our military
has a lot less influence on our society. We've got utilities actively
deploying this stuff, and while it is far from being everywhere, it is
a real threat in some areas. I suppose they could not care less about
implications of BPL for the military. They just do good lobbying,
and they have shown their political influence in many issues in the
past.

Don't count too much on the military. They might just use this as
an excuse to get funding for a new satellite based infrastructure or
other alternatives. Moreover I suppose HF is most valuable to the
military in crisis regions, where there is no BPL anyway ; )

/ralph

"Ralph Aichinger" wrote in message
...
In rec.radio.amateur.policy CW wrote:

As I have written, BPL devices *do* have the possibility to keep out
of *some* HF frequencies AFAIK. Ham radio would not be the first candidate
for this. Air mobile and military users would be more likely to benefit
from it.

And maybe it is a different perspective here in Austria, as our military
has a lot less influence on our society. We've got utilities actively
deploying this stuff, and while it is far from being everywhere, it is
a real threat in some areas. I suppose they could not care less about
implications of BPL for the military. They just do good lobbying,
and they have shown their political influence in many issues in the
past.

Don't count too much on the military. They might just use this as
an excuse to get funding for a new satellite based infrastructure or
other alternatives. Moreover I suppose HF is most valuable to the
military in crisis regions, where there is no BPL anyway ; )

/ralph

Will BPL have the same effect on military radio as it has on radio
hobbyists? Don't they have spread spectrum capability which is highly
resistant to interference?

Frank Dresser

"Brenda Ann" wrote in message
...


Thing is, BPL is also spread spectrum.. would not two spread spectrum
systems on the same bands interfere with one another??





I don't know alot about spread spectrum, but it's my impression that the
receiver and transmitter are in sync. If the interference doesn't match the
expected synchronization, the receiver ignores it. Also, the bandwidth of
spread spectrum is so wide that spread spectrum operations would have to
overlap, otherwise there would only be a few allowable channels.

But, any spread spectrum experts out there are free to correct me.

Frank Dresser

They probably do but not in widespread use nor is it likely to be. They do
also have the capability to replace most of that HF traffic by satellite.
They did, at one time, start to scale back the HF ops in favor of satellite
but decided that was a bad idea from a reliability standpoint. They do have
the satalite capablity but maintain HF to. The military, in any case, is
only a part of the government HF operation. If bpl has the capability of not
using certain segments of the band, due to the amount of space that would
have to be left alone, the bpl spectrum is going to be pretty holy. In any
case, I really don't think it is a viable technology, I seriously doubt it
will be the major rf disaster that some are saying it will be and I don't
think it will last long if it gets off the ground at all.
"Frank Dresser" wrote in message
...

Will BPL have the same effect on military radio as it has on radio
hobbyists? Don't they have spread spectrum capability which is highly
resistant to interference?

Frank Dresser

Ralph Aichinger wrote:
In rec.radio.amateur.policy Frank Dresser wrote:


When I wrote "vunerable BPL is to interference", I meant how outside sources
of interference would effect the performance of BPL. Sorry if I wasn't


[..]


If you know where this is all explained in depth and well documented, please
point me in that direction.


I don`t know the details, but here in Europe several pilot projects
were basically stopped and several larger companies got out of that
technology again, after trying to hype it for several years.

I do not know if this is due to unreliability or due to other factors,
but it *seems* to have worked better in the lab than in the real world.
If enough problems make it too unreliable and/or expensive, this might
be the easiest way out.

I wonder if the lab has defective transformers that spew out rfi? I
wonder if the lab regulary simulates lightning strikes on the lines
carrying BPL? I wonder if the labs simulate the sometimes awful
antiquated power lines that the signal would have to go over?

- Mike KB3EIA -

Brenda Ann wrote:

"Frank Dresser" wrote in message
...

Will BPL have the same effect on military radio as it has on radio
hobbyists? Don't they have spread spectrum capability which is highly
resistant to interference?

Frank Dresser


Thing is, BPL is also spread spectrum.. would not two spread spectrum
systems on the same bands interfere with one another??

Yes, but to a limited degree.

One characteristic which distinguishes a spread-spectrum
(whether frequency-hopping, or direct-sequence) system from
a channelized one, is the gradual way the channel
signal-to-noise ratio can degrade as more stations are added
in the same spectrum space. This "graceful degradation" is
in stark contrast to interference in standard
single-frequency applications, where a collision of two
signals means no link.

Think of two different transmitters sharing the same 1000
frequencies. Each "hops" to a new frequency every few
milliseconds at most. If both systems use different channel
sequences, it's just occasionally that both would land on
the same frequency and interfere with each other. And even
in this case, the total amount of time where they're
mutually interfering is perhaps a millisecond or less. So
the extra signal sharing the frequency has mostly the effect
of making the channel a tiny bit noisier for all users, but
not to blot out other signals.

As you add more and more spread-spectrum stations, the
probability of a "channel collision" of course increases.
However, by carefully choosing the sequences and making sure
they don't accidentally "lock horns" in synch for a while
following the same sequence of frequencies, the quality of
the link degrades slowly with each new station.

I suspect this "graceful degradation" property of spread
spectrum is more of a driving force than the potential
security and stealth that this system provides. It allows
more users to share the same small frequency slice, than
would be possible if you just put narrow-band FM equipment
and jammed them together as close as possible.

Funny how often unexpected benefits spin off of basic
research. Here's to renewing science and basic research.
Not everything important to business can be measured in
quarterly profits. Our competitors, who seem to get this
better than a lot of US companies do, will eat our lunch for
us if we don't start thinking long-term again. IBM and HP
"get it". It's Congress that we need to wake up next.

-- Ross

You're right about that. Unfortunately, the standard business plan is to
make as much as you can in the short term and then dump the company. They
have no interest in anything that won't pan out in 6 months.
"Ross Archer" wrote in message
...
Our competitors, who seem to get this
better than a lot of US companies do, will eat our lunch for
us if we don't start thinking long-term again. IBM and HP
"get it". It's Congress that we need to wake up next.

-- Ross

"CW" wrote in message news:uca3b.278911$uu5.62460@sccrnsc04...
They probably do but not in widespread use nor is it likely to be. They do
also have the capability to replace most of that HF traffic by satellite.
They did, at one time, start to scale back the HF ops in favor of satellite
but decided that was a bad idea from a reliability standpoint. They do have
the satalite capablity but maintain HF to. The military, in any case, is
only a part of the government HF operation.

Right: Didja ever add up the number of published MF/HF freqs just the
Coast Guard and the HF air traffic controllers use?? And those are
just a few of the published gummint-used freqs. Then come who the hell
knows how many unpublished freqs also used by other civil gummint
types.

If bpl has the capability of not
using certain segments of the band, due to the amount of space that would
have to be left alone, the bpl spectrum is going to be pretty holy.

It would be one big hole, "selective BPL interference" is a ridiculous
and completely unworkable concept.

In any
case, I really don't think it is a viable technology, I seriously doubt it
will be the major rf disaster that some are saying it will be and I don't
think it will last long if it gets off the ground at all.

If it's allowed to get off the ground at all a huge amount of damage
will be done even if it does eventually peter out. The closing the
gate after the cows get out syndrome, etc.

As far as BPL being an RF disaster is concerned I've travelled twice
to one of the BPL pilot areas specifically to listen to the stuff
hands on. Been there, done it myself and I need to tell you that yes
BPL is a potential HF/VHF disaster which needs to be squashed *before*
it even gets off the ground.

Anybody who belives otherwise needs to get off their butts and away
from their keyboards, pack up a rig and actually go listen to stuff
before they spout off about it.

Brian Kelly w3rv

"Frank Dresser" wrote in message ...
"DickCarroll" wrote in message
om...
"Frank Dresser" analogdial@worldnet




Hey Frank, where'd you ever get the idea that radio *isn't* open to
the public?
I never knew anyone whatever who wanted a ham radio license who was
barred from getting one. There is a small matter of qualifying for it,
of course, as there is in every endeavor where others can and will be
impacted when the licensee knows not which way is up. But it has
always been open to all comers.


OK, amateur radio is open to the public. But nearly all amateur radio
activity is either contacts between hams or some sort of test. I'm under
the impression that amatuers broadcasting what might be considered
entertainment programming to the public is banned. Am I wrong about that?




No, sounds accurate to me.



Now if you're talking "open" like CB is open, that's a horse of an
entirely different color.

Dick

More like pirate radio. I've heard some very entertaining stuff, and I hope
to hear alot more. I know that time can be bought on an independent
broadcaster, but I'd really like to know why what Alan Maxwell and the other
do is illegal. I think hobby broadcasting would bring alot of positive
interest to SW radio.


As always,it's a $$$$$ thing, of course.