Topband: Unique Short Radial Challenge
b38 at hilding.com
Sat Oct 20 20:02:29 EDT 2007
TNX to all for the multitude of direct emails, suggestions, etc.
I hope any resident TopBand "Physicists" can either confirm or deny the
validity of this info I just ran across in my research:
That Fact of physics is called RF Depth of current penertration or skin
depth. What this basically means is that as you sink RF current deeper into
any material the loss increases. There is a transitional zone where the loss
is considered acceptable equating to 37% of RF current loss this is the skin
Depth. The SKin depth of Salt water is fairly uniform and is about 7 inches
at 1.8 mhz and 2 inches and 30 mhz. Once you go below 7 or 2 inches its like
installing your ground system under a copper plate the losses are so great
and none of your RF current will return to the antenna feedpoint to be
radiated. Its that simple.
If this is true, I'm open to ideas for how to handle affixing some radials
into the salt water with a 12 foot tide fluctuation, so that I stay within
the 7 inch depth zone. This may have to be done in the rain with very high
winds. Umh, I'm now having second thoughts about this trip, but it's all
booked so I gotta grind-it-out :-)
Tnx & 73...
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