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The antenna exhibits more than a 40 kHz wide 2:1 SWR Bandwidth as shown in the graph above
which is a screen shot from a calibrated
Agilent 8714ET
Network Analyzer.
Using an Icom IC-718 Radio with an internal tuner DX Engineering Design and Test Engineers
were able to reduce the SWR at the 2:1 points down to 1:1 easily. This will extend the use of the
antenna significantly beyond the 2:1 points shown above. Almost any radio with a built in tuner -
and certainly with an external tuner of any reasonable ability - will be able to do the same.
The adjustment of the Series Coil and the top-hat will allow wide excursions inside and slightly
above and below the 160 meter band, if desired. DX Engineering will not be able to supply detailed
instructions for this but basic antenna principles will apply: A larger top-hat or use of more of the
Series Coil will lower the frequency whereas a smaller top-hat or using less of the Series Coil will
raise the frequency. The adjustment of the Shunt Coil will reduce the SWR.
Locking the Pivot Base
To help prevent accidental pivoting, ensure the four pivot locking
bolts are in place and properly secured. Additionally, you may replace
one of the bolts with a padlock to further prevent tampering or
accidental pivoting as shown below.
Ensure all four Pivot Locking Bolts are in place
Padlock used in place of one Pivot Locking Bolt
