w2pm@aol.com wrote:
>
>
>
> . So give some consideration to either a
> square or delta (triangular) top hat supported by corner supports that
> drop
> the vertical wire. Two cross wires (on the square wire top hat) with the
> vertical drop in the center or three intersecting wires for the
> triangle top
> hat should save space, improve efficiency, and allow for a lower vertical
> overall height. The "T" is simple and easy but does require some real
> estate, whereas a smaller profile top hat will do the same thing or
> better
> (cancelling high angle useless radiation) as described.
> Herb Schoenbohm, KV4FZ
>
> Pete W2PM Replies:
>
> But how can a top hat device be supported with a vertical wire? Ive
> seen some on 60 foot vertical masts but I don't think you can do this
> with a wire or a small gauge tapered 60 ft mast. This is why I
> wonder if under these circumstances a top load coil with a shortened
> (100 ft top wire) would be more feasible as you can hang the coil from
> the rope which holds up the vertical wire...
>
> Pete, the wire flat square, rectangle, or triangle quasi top hat
> supports the vertical drop wire, rather then a center vertical
> holding up the top hat. No center pipe or pole are needed. The wires
> that forms the top hat are supported by wooden mast or trees carried
> up on a nylon rope halyard and can be lowered to the ground for easy
> maintainence. The skelton flat top will provide considerably more
> capacity to the ground capture area then a "T" IMHO and make the lot
> size (except for the ground radials) more reasonable for a high
> performance 160 meter vertical. Top loading a mast or evena tower
> with sloping wires has a point of diminishing returns due to
> cancelation of the very same element you want to radiate. I believe
> past 20 per cent of the over all mast height is about it. However, a
> truely flat top T, or the flat top box or triangle will not work to
> the detriment of the vertical portion or vertical dropwire.
Herb, KV4FZ
>
>
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