For the historians on the list, one of the first amateur radio transmissions
heard across the Atlantic Ocean occurred during the sponsored ARRL
transatlantic tests in 1921-1922. Station 1BCG in Greenwich, CT used a
modified "T"-top Marconi vertical at a height of 70 feet. The top-hat span
was 100-ft.
The classic Marconi-fed system was modified in the sense that the base-fed
antenna was not referenced above an earth ground or a buried ground system.
Instead, Armstrong and Cronkhite used a resonant elevated radial system at ~
10 feet above ground. In the link to the photo below, you can clearly see
the elevated radial system located to the top and rear of the "shack."
http://users.erols.com/oldradio/eha47.htm
I had thought that elevated radial systems were a recent revelation of the
past couple decades. So, when I recently read a detailed description of the
1BCG antenna system I was surprised to learn that elevated radials were
employed ca. 1920. This was well before the buried-ground radial research
conducted by Brown-Lewis-Epstein in the early '30s.
With 1BCG's 70-foot radiator, 100-ft horizontal top-hat, and extensive
elevated radial system, I suspect that antenna would provide a "gangbusters"
signal by today's standards.
Paul, W9AC
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
|