Having a few days off from work for the Holidays, I have been reading the
ARRL
Antenna Compendium Vol. 6. There is some fasinating data in the two
articles by N6BV (Using HF Propagation Predictions, and Antennas Here Are
Some Verticals on the Beach) dealing with the use of verticals near salt
water. My thoughts are - how to obtain these results at locations away
from salt water. In looking back at the 18th Edition of the ARRL Antenna
Handbook, it appears that saltwater represents a ?perfect ground.? And
right on the beach, you have a perfect ground in both the near field and
far field. It appears that with 120 radials of 1/2 wavelength, you can
obtain a reasonable perfect ground in the near field (re Ant. Hndbk. Chpt
3 - Table 1). Realizing that it would be impractical to try to obtain a
far field perfect ground in all directions (360 degrees), what about
trying to implement this in one direction? For those of us on the East
Coast, 45 degrees puts one right in the center of Europe. Could it be
posssible to use those receive Beverage antennas as an extended radial to
simulate a far field perfect ground in at least one direction? Is a 1000
ft Beverage still too short? Or, does one need more than just a single
wire? OK, what if - "on the way to Grandma?s house" Saturday, I happen
across a wreck in which the chicken wire truck spilled several hundred
rolls? Do I quickly load them and spend next week spreading them
end-to-end as far as they will go in one direction?
Happy Holidays
73,
Henry Pollock - K4TMC
Raleigh, NC
k4tmc@juno.com
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