Re: Q: Biquad Antennas


Arthur Shapiro wrote:
In article <tu4jb2ld34mhj8a0tbnr1gec07iee24j5a@xxxxxxx>, Jeff Liebermann <jeffl@xxxxxxxxxxxxxxxxxxxxxx> wrote:

You rang? I've been wanting to rant on the topic of biquad
construction. There are far too many erronious biquad articles.


So after digesting your pleasantly voluminous message (thank you!), let's see
if I understand. I was really hoping to mount the N jack on the ground plane,
and it sounds like that is OK, even if not universally done in your
references.

But you assert that the critical factor, whether or not the jack is
electrically connected to the ground plane, is that short 15-18mm
gap between the jack and the actual antenna. It HAS to be a piece of coax -
the alternative of two soldered pieces of copper wire or a notched cylinder
of half inch copper pipe will severely detract from performance. Correct? I
assume that's an SWR issue.

And doubtlessly the scraps of cable TV coax I have about the house are the
wrong impedence.

Art

If it is really necessary to use a coax fed, then I would solder the
copper pipe to the ground plane. If the RG-8 insulator isn't inserted,
then you can blast the pipe and copper with a torch without fear of
melting. So scratch the epoxy I mentioned in the other post.

I built mine just using copper wire to reach the biquad. However, I
don't have any gear to measure SWR at wifi frequencies, so my
construction may not be optimal.

.

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