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Frequency pollution: retrograde

>From the recent Mode B vs. Mode J postings it appears that 2m frequency pollution is declining in some parts of the world (notably Japan) while still a problem in South America.  As cellphone networks profliferate in other parts of the world I suspect 2m will become less polluted.

In the U.S. (and in other "developed") countries there is more and more pressure on the frequencies above 2GHz for wireless telephones and networking applications.  This trend is certain to continue.

With these stipulations, it would appear to me that Mode A is becoming an attractive alternative again.  A RS15-type orbit provides very good coverage, and the buy-in in terms of equipment is relatively low.

At the Bangor Symposium we had a presentation from some uSat people about the birds that various college programs had in the works and the uSat launcher system.  I had some good discussions with several people about a Mode A satellite consisting of two sections, each three standard cubes high, connected with a spring steel tape that would be the 10m antenna.  The 2m omni antennas would be at the opposite ends of each section.  Covering four faces of each subsection with solar cells seemed to provide a reasonable power budget, as I recall.

I know I'll probably be shot down in short order, but I wanted to put in my two cents worth.  I *liked* Mode A.  That's how I made my first sat contacts and I worked most of the states for my WAS-OSCAR on RS15.  The Mode A birds were *fun* and I miss them.

Dave Reinhart

Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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