Look ma, no aerial!

[predator at cat.org.au]

Reply-to: predator at cat.org.au

I'm in the process of getting enough cash to start another wireless
project, but this time using not helicals but a high-gain omni, and an AP,
not an ancient monochannel ISA wavelan with mutant SMZ sockets on it.

Now, there's great omni's around but I dont want to buy them if poss, and
instead make my own. (leaves more money for lightning arrestors, etc).

However, based on some of the pics at
http://www.qsl.net/n9zia/wireless/pics/2.4colinear.jpg

it looks probable that one can dispense with an aerial per se, altogether,
and just stick a straight run of good coax (like, say, my surplus LMR400)  
in the air with precisely placed cuts in the shielding . This brings with
it some nice advantages, to wit, no connector losses, and given enough
cable, pretty much arbitrarily large gain. Dunno about the down-angle,
though 8-(
 
LMR400 is great stuff but its OD is much larger than the suggested
5mm... and this design looks to use a hell of a lot of PTFE tape
too... maybe the PTFE could be dispensed with, and an appropriate
diameter of straight copper pipe just fitted straight over the outside of
the LMR coax.

Has anyone tried this in this group? Or anywhere? Please scream, or laugh,
or something, if you feel it's doomed to fail 8-)



Cheeries...
<predator>