K8DO added on query about merit of longer radials on (or in ground)
folded back when in a tight space:
>An old AM broadcast engineer I know is also a ham and I have chatted with
>him on 80 meters... He uses a 1/4 wl. vertical antenna... He has a 4 foot
>square (4' x 4'), 10 ga., copper plate with a hole for the base insulator
>to pass through... He does not use radials... He gets out just fine and
>feels that the plate is not a compromise in gathering the return currents
>compared to the usual radial system that a city ham can get down... He has
>the room for some radials and states that changing to the plate increased
>his field strength over the previous radial system enough that he no
>longer uses radials...
>I mention this as an item of interest for those who cannot put out radials
>that perhaps the cost of a copper plate may be a fair return for
>performance....
>
>He did state that thin copper sheathing as for roofs, etc., is not as
>efficient as a plate with some thickness of ~ 0.100" or more - and that it
>wants to be a single plate, or if pieced together should be continuously
>soldered at the joints......
I would imagine that chap had good soil conductivity, especially some
distance away.
First two meters of the vertical would be right up against a 2m tall
brick-&-concrete wall in the same three directions I can run out
radials, but I am in a valley with abandoned farm land that gets rather
moist in strategic directions (as well as stay that way, judging from
the mosquitos).
Thanks for sharing that - you've got me thinking... ;^)
73, VR2BrettGraham
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