Topband: "T"-Top Vertical Antennas

[donovanf at starpower.net]

A further description of the 1BCG station can be found here

http://www.radioclubofamerica.org/history.php?page=1921.html

73
Frank
W3LPL

---- Original message ----
>Date: Fri, 24 Jul 2009 11:59:22 -0400
>From: "Paul Christensen" <w9ac at arrl.net>  
>Subject: Re: Topband: "T"-Top Vertical Antennas  
>To: "'TopBand List'" <topband at contesting.com>
>
>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