Hi Jerry,
> I am planning to put up a 2 wire beverage. What is done for the ends
> of the antenna. I have read several articles that you can leave one wire
> open and ground the other ? Another scheme is to use a termination
That won't work very well. The theory behind that concept is totally
wrong. It is not the electrical equivalent of a reflection transformer.
> transformer. If a termination transformer is used what is the core /
> winding information ? What is currently in use ? All ideas welcome !
I wrote a tech note in Communications Quarterly several years ago,
and I think there is something in ON4UN's book.
Basically you need either an autotransformer or a dual winding
transformer with one winding center-tapped on the far end. I used
the dual winding in my Beverages, because I could use the same
transformer in multiple uses. Either one works just as well.
It's too long to post, you'll have to read the articles. By the way,
pick a core material with an impedance that peaks on 160 meters!!!
If you use too high an initial permeability, the core impedance will
peak far below 160 and you'll need to use more turns!!!
73, Tom W8JI
w8ji@contesting.com
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