Topband: "T"-Top Vertical Antennas

[Paul Christensen]

> "The Proceedings includes many photographs of the antenna, unfortunately 
> only a few of us have access to this fascinating book.  However, many 
> pages of February 1922 QST describe the 1BCG station, the DXpedition to 
> Scotland, and the results of this first successful DX Contest."

Frank, I had nearly forgotten about the February 1922 issue of QST.  Better 
than a photo, it shows a detailed drawing of the "T" top-hat connection, 
including a bird's eye view of the elevated radial system.

Notice the antenna system was resonant at ~ 190 meters (operation back then 
was regulated to "200 meters and down").  The article describes the 
measurements taken between 200-330 meters and "resistance" is reported to 
vary between 40 ohms at 200m to 9 ohms at 330m.  There's an abrupt change at 
290m owing to mutual coupling from a nearby Rx antenna.  I'm not sure if by 
"resistance" they meant complex impedance or radiation resistance.  In 
either case, it would be an interesting exercise to model the 1BCG antenna 
today and compare results.

Paul, W9AC