Topband: 240' tower

Tom Rauch
Mon, 7 Feb 2000 12:00:07 -0500

> This is very hard to do..a half wave wants voltage on the bottom and I
> assume the bottom of the tower is grounded and not insulated. To make it
> work you would have to tap up the tower 20 or 30 feet  with a very low
> loss gamma system and try to resonate that bottom piece with a high
> voltage capacitor. You would then electrically have your 1/2 wave tower
> sitting on a 20 foot insulator. This has the risk of being very
> lossy...the voltages are high...and the bandwidth narrow. John  K9DX

Not only that, a tapered tower looks much shorter electrically than 
a uniform cross section tower. 

The 240 foot tower will probably work more like a 1/4 wl tower than 
a half wave, which might be a good thing.

I have a 318 foot uniform cross-section tower on an insulator, and it 
is actually much worse than a 200 foot tower at night for most 
distances (as much as ten dB). It is a few dB better during 
daytime, especially on groundwave.

73, Tom W8JI

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