Paul, AB0SI wrote:
"hmmm, this stuff I have read on NVIS says 0.1 to 0.2 wavelengths."
Yes, and I said 0,25 and explained how I arrived at that figure. So, I
went to page 3-11 of the 19th edition of the ARRL Antenna Book to look
at Fig 12.
Fig 12(A) is for 1/8-WL high and Fig 12(B) is for 1/4-WL high. Paul is
supported by Fig 12 because the 1/8-WL high antenna appears to have more
radiation toward the zenith than does the 1/4-WL high antenna.
I don`t know why, but would speculate it is due to closer coupling of
the radiator with the earth which gives the reflector (earth) more
energy to work with on the reflection. Maybe I`ll learn something from
this bum steer. I learn something nearly every day here and find this a
rewarding experience.
Best regards, Richard Harrison, KB5WZI
|