[Elecraft] Watch the ions

Tue Feb 26 18:52:17 EST 2013

Interesting aside...

I worked for an In-Flight Entertainment development firm, and our premier product line was a series of Ku-band sat receivers for EchoStar (Dish).  The EchoStar footprint drops off severely at US borders.  Dish had a similar restriction to the one that Ron found re PBS.  In addition to the signal level problem at the borders, the sats' antennas "hotspot" metro areas, so that smaller dishes may be used in population centers.  In the middle of flyover country, a bit more of a ground station antenna is needed to maintain link margin.  Link margin and antenna budget being what they are in that business, we developed a steerable airborne antenna based on an array of Luneberg Lenses and it worked well.  At least it worked well away from borders and in metro areas...

Unfortunately, the System Engineer that developed the antenna specs lived in a city, and far from borders.  The EchoStar spec said nothing about the 
contour of the signal, and how it varied.  Link margin as-designed was 1.5 dB (a reasonable margin, so I'm told).   So far so good.

US air carriers sometimes stray into Canadian airspace, and this depends on the flight plan.  US carriers also fly right over the center of the country.  We designed with an affordable ink margin, but not enough to cover the contour dips at borders and in flyover country.  We got into big trouble with the airlines because of LOS occurring in these two circumstances.  This involved a lot of penalty money changing hands, and a lot of free flights for our engineering staff to try to work out the problems (which is when we figured out the variable link margin problem).

The amount of trouble we got into when Dish found out about airline passengers viewing US-licensed live content in Canadian airspace cause the earlier problem to fade to complete obscurity however.

Live and learn.

Matt Zilmer, W6NIA
Pecca Fortiter

-----Original Message-----
From: elecraft-bounces at mailman.qth.net [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Ron D'Eau Claire
Sent: Tuesday, February 26, 2013 3:13 PM
To: 'David Ferrington, M0XDF'
Cc: elecraft at mailman.qth.net
Subject: Re: [Elecraft] Watch the ions

Aha! I missed the second link. That is not a NASA link. It's a link to a video produced by the US Public Broadcasting System (that's the pbs in the URL). 

So I dug into the PBS web site FAQs and found this for viewers outside of the USA:

"While over-the-air broadcasts can reach beyond U.S. borders into Canada and Mexico, online video is subject to geo-filtering, which restricts the areas that can view PBS content. PBS is legally obligated to ensure each program does not exceed its granted rights, which unfortunately eliminates international streaming ability for some PBS programs in Canada and elsewhere. 

"You can find our Internationally Available collection, which is a compilation of programs that can be viewed outside of the United States, at:

Internationally Available Collection 

"We regret not being able to offer all our content online to our supporters."

The internationally available collection link goes to www.video.pds.org

I don't know if that will open for you, or if they program is in there. I suspect that it is not or the other link would have worked. 

I have the same problem with BBS broadcasts here. Some of the on line stuff is blocked in the US, especially the classical music on line. So I make do with radio Netherlands and practice my Dutch ;-).

73 Ron AC7AC

-----Original Message-----
From: David Ferrington, M0XDF [mailto:M0XDF at Alphadene.co.uk]
Sent: Tuesday, February 26, 2013 2:20 PM
To: Ron D'Eau Claire
Cc: 'Bob'; elecraft at mailman.qth.net
Subject: Re: [Elecraft] Watch the ions

Hi Ron, the link to the SME works fine, it's the second link
(http://video.pbs.org/video/2226474716/) that doesn't.
73 de David, M0XDF
We are what we repeatedly do. Excellence, therefore, is not an act but a habit. - Aristotle

On 26 Feb 2013, at 22:15, Ron D'Eau Claire wrote:

> Use this link in the U.K. I'm surprised the original link won't work
there. 
> 
> http://www.star.ucl.ac.uk/~apod/apod/astropix.html
> 
> or for the Netherlands (It's even in Dutch):
> 
> http://www.apod.nl/ap130226_nl.html
> 
> 73 Ron AC7AC
> 
> 
> -----Original Message-----
> From: elecraft-bounces at mailman.qth.net 
> [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of David 
> Ferrington, M0XDF
> Sent: Tuesday, February 26, 2013 8:33 AM
> To: Bob
> Cc: elecraft at mailman.qth.net
> Subject: Re: [Elecraft] Watch the ions
> 
> Looks like it might be very interesting, but not available in the UK 
> :-(
> 73 de David, M0XDF
> --
> Study without desire spoils the memory, and it retains nothing that it 
> takes in.  -- Leonardo da Vinci
> 
> On 26 Feb 2013, at 16:20, Bob wrote:
> 
>> You may also enjoy the Nova "Secrets of the Sun" show which can be 
>> viewed below.  This is a 54 minute long show that does a great job of 
>> explaining how the sun works and the new field of helioscience.
>> 
>> http://video.pbs.org/video/2226474716/
>> 
> 
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