Topband: Top Loading Advice

[Chortek, Robert L.]

Fellow Topbanders,


I just finished replacing my damaged base loaded vertical and have a question about the optimum amount of top loading.


A bit of background - my new vertical is a 55' #12 wire supported by a 60' Spiderbeam fiberglass pole.  At the top there are 2 -41' top loading wires running roughly at 180 degrees from each other, angling down at about 45 degrees.  The ends are at about 25' . Since the resonant point is about 2 MHZ, I am still using an air core base loading coil 6" in diameter made of No. 8 solid copper wire to bring it to resonance at 1825 MHZ.


I could lengthen the top loading wires somewhere between  4 - 10' each (and reduce the amount of base loading needed), but it will bring the ends to within about 15' and  20' of the ground.


My question is this:  At what point will lengthening the top loading wires and bringing the ends closer to ground offset the improvement gained by reducing the amount of base loading?


As it is, the antenna is a HUGE improvement over my base loaded vertical (on the order of 6-9 db from stations in the RBN within the ground wave).


Should I leave it alone and be satisfied with the improvement or lengthen the top loading wires. If so, by how much?


Thanks in advance from any advice.


73,


Bob/AA6VB