Topbanders
I have been reading the thread about the drooping with much interest...
I am getting ready for some antenna work myself.
Using eznec 3.0 I modeled a 30 ft vertical over 4, 1/4 wl radials.
First one was base loaded no cap hat.. It took 73uh to load and showed -14
dbi..
Second one was also base loaded and had 4 108" whips at the top, It took
36uh to load and showed a -10.7 dbi ...
Third one drooped the cap whips at 45deg,it took the same L(36uh) to load
and showed -11.5 dbi.
I used an R in the load of 2 ohms for the small L value, and 4 ohms for the
large..
Im a bit vague as to what to put there for real world stuff..I have a 78 uh
bugcatcher
coil that has a .5 ohm resistance and a hi gain that is close in L that has
3 ohms resistance.
So based on the past discussions on rf resistance being a different animal,
I hope I used the correct values.
At any rate the results seem to show even if the cap hats droop they are
still better thanjust using L.
Bud W0HG
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