Cebik thinks these things use an 800 to 900 ohm terminating resistors
and a 16:1 transmission line transformer.
http://www.cebik.com/wire/wbfd.html
I too would like the specific data on the B&W. I have modeled it, but I
used a lot of guess work for the details.
Jerry, K4SAV
Jim Lux wrote:
>I'm looking for some details on the dimensions and design of the Barker and
>Williamson "folded dipoles", for the purposes of building an accurate NEC
>model.
>
> From some casual web searching (on TT, among other places), it looks like
>these things are basically a folded dipole with a resistor in the middle of
>the fold.
>
>I'm looking for things like detailed dimensions (how far apart are the two
>wires?)
>What's in the "coax to antenna transition"? Is it a balun? Or, is it just
>two wires?
>What's in the "magic box" at the top of the antenna (a resistor? a tuning
>network?)... the photo on the B&W website shows a metal strap between the
>magic box and the coax, but it's not clear if that's an actual electrical
>connection (if so, to what)
>
>I'd also be interested in any measured performance data (who knows.. the
>gov't uses them, maybe someone actually tested one on an antenna range
>somewhere?)
>
>Thanks, all...
>
>Jim, W6RMK
>
>_______________________________________________
>
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
>questions and ask for Sherman, W2FLA.
>
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>
>
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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