SWR SCANS

Graph A is of a single element at full height (65 feet) with 180 foot of 3/4 Andrews hardline. Measurements being made in shack. There was no reduction balum, just ferrite around the coax at the antenna. It can be seen from the multiple curves that the multiple resonant points associated with the G5RV are evident. The varying of the capacitance show how the SWR can be moved at any particular frequency such that a composite SWR curve can be generated that can be aligned with the amateur bands. But as with the G5RV a tuner would have to be used to make the single element a viable antenna.

Graph A
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MHZ

Graph B is the same element as above except a 4:1 balum was introduced at the antenna to bring the antenna impedance down. The addition of the balum helps the general composite SWR of the element though it is suspected that much better improvement could be seen if better matching could be pursued. The SWR curve is much more continuous with frequency change, but it is suspected that balum losses do contribute to this.

Graph B
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MHZ

It is evident that from the above that there is some similarity with the G5RV antenna with its multi-frequency responses. Though not as large as the G5RV, its possible lack of comparible gain (G5RV has a collinear effect) on the higher bands are compensated by its ability to be rotated and having the signals emanating away from the normal ground losses because of the probable increase in height. Difficulties associated with the G5RV antenna with respect to the exact length of the stub with respect to the surrounding terrain are now overcome with the remote tuning ability. It is to be noted that the above single element dimensions were selected as part of a two element beam. The above measurements were taken as a prelude to a review of the final antenna. However the single element did not provide directional abilities from 10 MHZ and down with bidirectional lobes being fully formed at 14 MHZ and above but with out the attendant side lobes obtained with the G5RV, i.e. still a bidirectional element.

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