Hi Jerry,
I posted the drawing on another newsgroup called
alt.binaires.schematics.electronic
Not all ISPs carry binairy files so maybe you can't see it, if your
address is good I'll
email the drawing.
I looked at the site and it discouraged me. One site says 34mm diameter
tube another
42mm, one says a 71mm impedance match strip then another says it's longer.
I have no
way to measure the antenna when finished so I'd like to at least start
with the right
dimensions. I will say at least the site you gave does have some equipment
and his
measurements and reasoning make sense.
What is a bridge? I plan on putting a Usb wifi adapter at the antenna.
I hope to remove the smt antenna on the USB wifi card and attach the
helical antenna.
Thanks, Mike


Hi Mike

I am too much 'a beginner' to be a good advisor for how to hook up devices
for WiFi reception. So, I wont try to define what a Bridge is. I will do
about anything (affordable) that allows the elimination of the coax in a 2.4
GHz system.
I do have some experience with making WiFi systems to extend the distance
at which Internet connections can be achieved. On one system I made for a
guy in Ranchita Calif, who has an agricultural business about 1/4 mile from
his house. I put an access point on a 4 foot diameter dish so he uses only
CAT 5 cable from his home Router to illuminate the dish. I then put a
Bridge on a smaller dish with CAT 5 cable to connect that dish to his lap
top in the field. It worked. My objective was to be able to use highly
directive antennas yet minimize coax line losses.
I think the use of a USB wireless adapter (TRENDnet TEW-445UB) Would be
easier than the way I made my system. Show Me cables sells reversing
polarity adapters that make it possible to use normal SMA connectors to the
TRENDnet USB TEW-445UB

Your project interests me. Tell me what you finally decide to do.
I have rejected the Helix. They are more difficult for me to understand
than a Yagi. The Helix is circularly polarized, so you loose 3 dB "off the
top" of any gain (directivity) plots. The Yagi is fairly easy to model with
EZNEC, so you can be fairly well assured that whatever you build will work
like the model.

Jerry