Topband: Electrical height of short shunt fed tower?

[Pete Michaelis - N8TR]

My experience is similar.  I have  100' of Rohn 45 shunt-fed at 60'
with about 50 radials.  When I first installed the shunt feed it had a
a 40-2CD ft at 108'  and a KT34XA at the top of the tower.  When I
later added a second XA on a ringrotor at 65' there was no
change required to the shunt capacitor.  Adding a third XA at 32'
(since removed) also had no effect.

73 Pete - N8TR

At 08:37 AM 11/10/2009, AA1K wrote:

>Anecdotal: In the 1980s, I had a 100-foot Rohn 25 shunt-fed tower with
>200 radials. On top was a 204BA (4-el Hy Gain 20m yagi). The mast
>extended 12 feet above that. Later when I added a 4-el 15-meter Wilson
>yagi (17-foot boom) at 112 feet, there was no change in the shunt tuning
>needed or in the SWR.