ARLA/CLUSTER: DX Engineering desenvolve antena vertical eficiente para 160m a ser usada na Dxpetion à Ilha de Bouvet

[João Costa > CT1FBF]

The Bouvet Island 160m Vertical

Tim Duffy, K3LR, reports: The DX Engineering and Bouvet Island teams
have worked together to design an efficient 90 foot top loaded 160
meter vertical antenna that can be installed quickly and safely on
Bouvet Island by the 3Y0Z team this January.

With a good radial system the difference in gain between a 120 ft
(full quarter wavelength) vertical and this custom 90 foot top loaded
vertical is less than 0.5 dB.

This vertical uses a custom designed heavy duty hinged pivot base with
base insulators to accommodate a 40 foot falling derrick 3 inch heavy
duty pipe for installation.

The vertical is base fed using two inductors to match to 50 ohms. The
first 70 feet of the vertical is Universal Aluminum tower (12 inch
face) and the top 20 feet is 1.875 inch diameter aluminum tubing.

There are guys at 30, 50 and 70 feet. There are also three 30 foot top
loading wires attached to the top of the tubing that are tied to
anchors
60 feet out from the base.

DXE is actually donating two of these vertical packages to the 3Y0Z
team in case one gets damaged (there are 300 storms per year on
Bouvet).

More details on the construction and the final test raising plus VSWR
measurements are shown in the video filmed and produced (in 4K Ultra)
by Greg, W8WWV. https://www.youtube.com/watch?v=bSw-0TjaUiU

OPDX