Re: antenna

On 12/19/2011 12:53 PM, gregz wrote:
miso<miso@xxxxxxxxx> wrote:
On 12/17/2011 7:59 PM, gregz wrote:
miso<miso@xxxxxxxxx> wrote:

I'm using a 5 foot piece of coax about the size of rg58. Not much to work
with.
From what I can tell, these antennas do require either a ground plane, or a
tube running over the coax to the connection a quarter wavelength.

I plan on placing the antenna on the outside of an aluminum screen, mounted
in a toilet paper dispenser, horizontally polarized to help interference,
sitting on the window ledge, about a quarter wavelength away from the
screen. I was looking in Kmart for suction cups or something, and noticed
the dispenser. Drilled out the ends, stuck antenna through.

Greg

It sounds like you are making a reflector and not a ground plane.

There is a reflector involved.

Greg

Have you considered building the biquad? It can easily be swapped from
horizontal to vertical polarization. Taking a tip from Jeff, I built one
using round loops rather than square. Just keep the circumference the same.

My point is you would probably get better results using a known design
with a bit of science behind it rather than just hacking.

http://martybugs.net/wireless/biquad/

I built one very similar to the Marty design. Instead of messing with the
pipe, I hacked an old N connector. Something like this would work:
http://www.frys.com/product/2924495?site=sr:SEARCH:MAIN_RSLT_PG

Of course when push came to shove, I just bought a high gain antenna. But
the hacked antenna was interesting, just to see what I could make.

Was that n a good one, like brass underneath, solderable?


Greg

Actually it was difficult to solder to the hack-sawed N connector. I used a small propane torch. You need to be careful not to melt the insulation in the N-connector. Maybe the pipe is a better idea if you have some pipe laying around. I doubt you could buy a foot of copper pipe, so you need to be able to transport the pipe, which is usually in 10ft sections. And you need a pipe cutter.

That's the problem with homebrew stuff. You need the tools.

I used the biquad wispying (like war driving, but with video) in Vegas. The biquad is pretty good for a little antenna. However the L-com panel antennas are relatively cheap and decent quality.

I trolled the net looking at reviews from WISP installers. They dissed quite a few antennas for leaking. L-Com was considered the best of cheaper products.

Hey, nobody was ever fired for buying Ubiquiti. Occasionally their gear shows up on ebay at reasonable prices. But for my money, a $40 L-Com panel goes a long way.


.

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