G'day Goose/Tom W8JI and all,
I guess when Stew Perry was writing this, there was a lot less readily
available data on earth systems than there is today. As you say, we now
know that a radial system does not have to be as big as Stew thought (for
example, according to some modelling I have seen, a mere 30 radials of 20 m
in length, spaced around 4 m at their tips, is less than 1dB down on a
full-size (120-radial) quarter-wave-radius ground screen.
However, W1BB gives a fascinating anecdote about ZE7JX who was trying to
work into VK6, with a 55' top-loaded vertical and 65 quarter wave radials.
For a long period of time, ZE7JX kept skeds with Mike VK6HD, night after
night, with no success. In desperation, he put down a further 128 quarter
wave radials and the very next night worked Mike plus another VK6.
Now the increase in radials should perhaps only have made a dB or less
difference to ZE7JX's signal. Maybe it was just a coincidence/change in
conditions that ZE7JX could suddenly work VK6HD... or was it?...
I guess you can never have too many radials (just in case).
161,
Steve, VK6VZ
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