measurement success
All,
As many of you may recall I have been trying measure and improve a
loaded vertical on 80 meters. The antenna is permanently mounted on a
radial field. The issue has been measuring and improving the performance
of that system. The predicted values are for the antenna element to have
a low impedance in the range of 6 to 10 Ohms. The ground is added to a
total impedance of 48 to 54 Ohms, depending on moisture.
As part of that process to determine the actual measurements I created a
2 meter model. The element is a loaded vertical from the ARRL
handbook. The ground is set of shortened radials. That antenna measured
a reflected power of 6.9 db at resonance. This calculates to an antenna
system impedance of about 18 Ohms. This is the range of the answer I was
looking for in the 80 meter antenna.
This is a good result. It confirms the range of predicted values for a
loaded vertical. The next step is to measure the actual 80 meter
antenna. That will result is a good ground measurement and support
ground a radial system.
- Dan
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