New Topband Vertical
A little late into the Topband season the new inverted L has been installed at SEØX, just in time for the CQWW SSB contest.
The vertical part of the inverted L stands 19 meter tall. The bottom 13 meters are made of 50, 45 and 40 mm aluminium pipe and the top part is four sections of an old Spiderbeam pole. The new vertical uses the old radial system consisting of two raised and bent radials following the shoreline. An unun is used to transform the 22 ohm impedance to 50 ohm and a RF choke is placed at the antenna to reduce HF in the coax shield. The 2:1 SWR bandwith is around 30 kHz.
Update Jan 29, 2010: The first construction of this antenna did not survive the the winter storms, and the antenna had to be repaired. The photo shows the repaired antenna.