Hello John
I, too, have experimented with base and top loading with verticals on Topband.
No question about it, the toploading is much better. Just take a look at your
feedpoint impedance with the base coil vs any sort of top loading.
One point to note, a specific coil that will resonate the base will not provide
the same loading if placed at the top...more "coil" will be needed if mounted
near the top of the antenna.
When I had a single 65' vertical with 90 radials resonated with T wire loading
I had a base impedance near 25 ohms...the same 65' vertical with a large EF
Johnson broadcast coil at the base gives me close to 10 ohms...ugh! I use the
base loading as it provides a cleaner installation vs. overhead loading wires
but if I had my druthers they would be top loaded with an 80M trap and "L" wire
to resonate on 160.
Top load if you can and let us know your results
73 de AG6X
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of
w5jmw@towerfarm.net
Sent: Friday, January 08, 2016 3:10 PM
To: topband@contesting.com
Subject: Topband: placement oc coil
Hello to all.I am planning a 60 foot vertical.I am wanting to either place a
coil on the vertical for topband.The vertical is a hy-tower.I have base
loaded(not very effective) I have toploaded with a single wire(not enough
room).I now have plenty of room.So my question.
Base load with many radials,60+
top load at the highest with wires?
top load with coil? and if this is best where should the coil be placed.
thanks to all es 73 john w5jmw
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