RE: [amsat-bb] Homebrew 70cms Crossed Yagi

["Howard Long" <howard@xxxxxxxxxxxxxx>]

Hello Greg

> I'm intrigued by your driven element design.  Half dipole,
> half folded dipole.  I've always had problems getting a good
> match to the coax.  Is it really as simple as looping the
> end back on one side?

The designer is Kent Britain WA5VJB. All I did was use a hacksaw.

But, suffice to say, the J pole DE configuration allows (a) the use of an
unbalanced feed and (b) raises the impedance to 50 ohms.

The problem is the potential for a non-symmetrical radiation pattern.
However, the reality is that in practice it works very well thank you very
much! Tuned right down to unity VSWR.

See http://www.clarc.org/Articles/uhf.htm and also the Spring CQ VHF for
more information about this design.

73 Howard G6LVB


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