"Richard" wrote in message ...
"Richard" wrote in message
...


Yet, I think whoever wrote note 688 expects a "designer" to put almost
whatever he wants for DE,

I'm not really sure about that. Maybe this is not expected, rather perhaps
there is an implication DE ought to be a folded dipole.

I doubt I would use a folded DE myself. More work... Normally, I
would just use a grounded DE, but in your case, you need to consider
how you would tune the antenna. IE: gamma match, etc...If you have no
radio that transmits, or an antenna analyser, it might be tricky..In
that case, probably the simpliest method would be to use a split,
carefully cut dipole DE, and hope for the best. The dimensions,
spacings, etc, are critical yes, but I don't think as critical as you
think. IE: I don't really worry too much about element mounting
methods, etc, when I build a yagi. Almost anything you slap together
should work pretty well as long as you measured carefully. When I once
made one for that purpose, I didn't have a transmitter. And I did use
a gamma match. I had no decent way to tune it up. So I just
guesstimated, and tuned the match for max signal, noise, etc..I don't
know how well it came out as far as the match, but the antenna worked
great.
A simple fast way to design an NBS yagi for any freq, is to use the
eznec demo. It has a NBS yagi as a demo, and it can be easily scaled
for any freq. MK