Diego Garcia is active again here this morning on 13254.

dxAce
Michigan
USA

http://www.iserv.net/~n8kdv/dxpage.htm

dxAce wrote:

Diego Garcia is active again here this morning on 13254.

Transmissions have a 'watery' sound to them, as they have the past few days
indicating a possible trans-polar path.

dxAce
Michigan
USA

http://www.iserv.net/~n8kdv/dxpage.htm

dxAce wrote:
Diego Garcia is active again here this morning on 13254.

Transmissions have a 'watery' sound to them, as they have the past few days
indicating a possible trans-polar path.

Does the cold make the radio waves shiver?

--
So those 380 tons of missing explosives were moved by Saddam before all
those expert inspectors noticed, eh?

No wonder twelve years of inspections found NOTHING.

dxAce wrote in message ...
dxAce wrote:

Diego Garcia is active again here this morning on 13254.

Transmissions have a 'watery' sound to them, as they have the past few days
indicating a possible trans-polar path.

dxAce
Michigan
USA

http://www.iserv.net/~n8kdv/dxpage.htm

Interesting - I will try to listen for them this weekend (no luck so
far...)

An observation and a question:

When a station is not antipodal to the listener (such as, say, Voice
of Nigeria or Radio New Zealand and my receiver in California), it
appears that there are only two ways a signal could reach the receiver
- either short path or long path via the Great Circle route, which
would be a straight line plotted across the Earth's surface, not
counting the Great Circle itself or the necesary skip. A signal
headed out in any other compass directions from the station in
straight lines would ultimately not arrive at the receiver, but at
some other point on Earth. (This is not the same as saying that a
station beaming its signal in some other ddirection will not reach my
receiver - we all frequently hear broadcasts intended for other
audiences, because antenna systems aren't perfect, thank goodness.)

This is why, when I listen to All India Radio or the Seychelles or
something out thataway that is *not* antipodal, it usually sounds
watery - it has no other route to my receiver except over the pole(s).

The only way a signal emanating from a station in any direction could
always reach a receiver is if the transmitter is antipodal to the
receiver - that is, directly on the opposite side of the earth. From
this, and without the immediate benefit of a globe or map, I assume
that for DxAce, Diego Garcia is nearly antipodal to his receiver; thus
his implication that signals from that site could possibly reach his
receiver via more than one path aside from a polar route.

*The Question*: Am I wrong? Is it possible, or even common, for a
transmitted signal to travel to a receiver via some route other than a
Great Circle route? Is it possible for skip to veer around corners?
People talk about and use Gray Line conditions to their advantage, but
even *that* is a straight line / Great Circle pathway when one
exmaines what is happening - are there others that weave along warped
ways?

Thanks -
Bruce Jensen

Do a Google search for skewed propagation

--
The Anon Keyboard
I doubt, therefore I might be



"bpnjensen" wrote in message
om...
An observation and a question:

When a station is not antipodal to the listener (such as, say, Voice
of Nigeria or Radio New Zealand and my receiver in California), it
appears that there are only two ways a signal could reach the receiver
- either short path or long path via the Great Circle route, which
would be a straight line plotted across the Earth's surface, not
counting the Great Circle itself or the necesary skip. A signal
headed out in any other compass directions from the station in
straight lines would ultimately not arrive at the receiver, but at
some other point on Earth. (This is not the same as saying that a
station beaming its signal in some other ddirection will not reach my
receiver - we all frequently hear broadcasts intended for other
audiences, because antenna systems aren't perfect, thank goodness.)

This is why, when I listen to All India Radio or the Seychelles or
something out thataway that is *not* antipodal, it usually sounds
watery - it has no other route to my receiver except over the pole(s).

The only way a signal emanating from a station in any direction could
always reach a receiver is if the transmitter is antipodal to the
receiver - that is, directly on the opposite side of the earth. From
this, and without the immediate benefit of a globe or map, I assume
that for DxAce, Diego Garcia is nearly antipodal to his receiver; thus
his implication that signals from that site could possibly reach his
receiver via more than one path aside from a polar route.

*The Question*: Am I wrong? Is it possible, or even common, for a
transmitted signal to travel to a receiver via some route other than a
Great Circle route? Is it possible for skip to veer around corners?
People talk about and use Gray Line conditions to their advantage, but
even *that* is a straight line / Great Circle pathway when one
exmaines what is happening - are there others that weave along warped
ways?

Thanks -
Bruce Jensen

"Keyboard In The Wilderness" wrote in message news:08tgd.82205$hj.10086@fed1read07...
Do a Google search for skewed propagation

Thank you - I'll do just that.

BTW, excellent reception this past weekend mornings of low-power
Indonesian stations here in California.

Bruce Jensen

bpnjensen wrote:

dxAce wrote in message ...
dxAce wrote:

Diego Garcia is active again here this morning on 13254.

Transmissions have a 'watery' sound to them, as they have the past few days
indicating a possible trans-polar path.

dxAce
Michigan
USA

http://www.iserv.net/~n8kdv/dxpage.htm

Interesting - I will try to listen for them this weekend (no luck so
far...)

An observation and a question:

When a station is not antipodal to the listener (such as, say, Voice
of Nigeria or Radio New Zealand and my receiver in California), it
appears that there are only two ways a signal could reach the receiver
- either short path or long path via the Great Circle route, which
would be a straight line plotted across the Earth's surface, not
counting the Great Circle itself or the necesary skip. A signal
headed out in any other compass directions from the station in
straight lines would ultimately not arrive at the receiver, but at
some other point on Earth. (This is not the same as saying that a
station beaming its signal in some other ddirection will not reach my
receiver - we all frequently hear broadcasts intended for other
audiences, because antenna systems aren't perfect, thank goodness.)

This is why, when I listen to All India Radio or the Seychelles or
something out thataway that is *not* antipodal, it usually sounds
watery - it has no other route to my receiver except over the pole(s).

The only way a signal emanating from a station in any direction could
always reach a receiver is if the transmitter is antipodal to the
receiver - that is, directly on the opposite side of the earth. From
this, and without the immediate benefit of a globe or map, I assume
that for DxAce, Diego Garcia is nearly antipodal to his receiver; thus
his implication that signals from that site could possibly reach his
receiver via more than one path aside from a polar route.

*The Question*: Am I wrong? Is it possible, or even common, for a
transmitted signal to travel to a receiver via some route other than a
Great Circle route? Is it possible for skip to veer around corners?
People talk about and use Gray Line conditions to their advantage, but
even *that* is a straight line / Great Circle pathway when one
exmaines what is happening - are there others that weave along warped
ways?

No, the grey line is not always necessarily a straight line path, but can be a
'crooked path', and that is 'veering around corners' as you say.

Hearing Diego this morning several times after 1425.

dxAce
Mihigan
USA

http://www.iserv.net/~n8kdv/dxpage.htm

dxAce wrote in message ...
bpnjensen wrote:

dxAce wrote in message ...

snips

No, the grey line is not always necessarily a straight line path, but can be a
'crooked path', and that is 'veering around corners' as you say.

Hmmm - can you explain this?

Geometrically, with the sun's rays essentially parallel to one another
shining on the disc of the earth, the grayline would always represent
a virtually perfect circumference, no matter which exact face the
earth presents to the sun - hence, while a flat map of the world shows
an undulating wave, the grayline is actually a 'straight' line along
the earth's face. The only deviation from this that I can determine
would be the astronomical width of the sun, about 0.5 degree, and
whatever 'ionic' width either side of that partial illumination at
sunrise/sunset would be involved in improved propagation.

I can imagine that something about the earth's magnetic field could
vary this, especilly *at* the poles - is this why some 'crookedness'
can occur?

Thanks,
Bruce Jensen

bpnjensen wrote:

dxAce wrote in message ...
bpnjensen wrote:

dxAce wrote in message ...

snips

No, the grey line is not always necessarily a straight line path, but can be a
'crooked path', and that is 'veering around corners' as you say.

Hmmm - can you explain this?

Geometrically, with the sun's rays essentially parallel to one another
shining on the disc of the earth, the grayline would always represent
a virtually perfect circumference, no matter which exact face the
earth presents to the sun - hence, while a flat map of the world shows
an undulating wave, the grayline is actually a 'straight' line along
the earth's face. The only deviation from this that I can determine
would be the astronomical width of the sun, about 0.5 degree, and
whatever 'ionic' width either side of that partial illumination at
sunrise/sunset would be involved in improved propagation.

I can imagine that something about the earth's magnetic field could
vary this, especilly *at* the poles - is this why some 'crookedness'
can occur?

It's very easy to see, just look at a grey line map.

It's a well known propagation phenomenon.

At least amongst the cognoscenti.

And, has nothing to do with the magnetic field.

dxAce
Michigan
USA

(bpnjensen) wrote in message . com...

*The Question*: Am I wrong? Is it possible, or even common, for a
transmitted signal to travel to a receiver via some route other than a
Great Circle route? Is it possible for skip to veer around corners?
People talk about and use Gray Line conditions to their advantage, but
even *that* is a straight line / Great Circle pathway when one
exmaines what is happening - are there others that weave along warped
ways?

Thanks -
Bruce Jensen

As suggested or implied by both of the other posters here -

I looked up issues related to this on the internet, starting with a
Google search for skewed propagation.

After looking over some fascinating information, I think that the
answer to this question is, YES, 'skewing' of signals does occur due
to varying degrees of geomagnetic activity near the poles and,
especially, the locations and degrees of its gradient. At points of
high gradient, and usually well away from the most absorptive regions
where radio signal fear to tread, radio waves can actually take rather
sharp corners from standard great circle (GC) routes, and go from one
GC to another. These are most easily noted by amateur radio
operaters, who can keep careful track of the bearings of their antenna
arrays and the bearings fo their contacts. A careful and
well-informed SWL could do as much, although as most of probably use
nondirectional wires, or wires of unknown direction, it is probably
far less likely.

And, NO, grayline propagation *alone* does not follow warped or skewed
routes, following the clearly-defined GC grayline - but like any other
propagation, can be susceptible to skewing by the geomagnetic
gradient.

And, best of all, sometimes the combination occurs of skewing from one
GC route to another and especially when one route is the highly
effective grayline route, wonderfully unexpected reception (or
transmission, if you are an amateur) happens.

So, for the pointers, lads, thank you!

Bruce Jensen