January 17 2005
So I did the unspeakable.
I installed a few Mesh nodes with out doing a site survey. One worked
extremely well and the other well, lets say I'm writing about it.
The problem is I had a small window of opportunity to install an
antenna on my buddies chimney.
It was January in Toronto and the temperature went up
to 12 C that day. Since the snow melted off the roofs I figure it
was a good time to install the antenna. And I did. No problem, I
had a visual sitting of the antenna that I wanted to mesh with so I went
and install it. Since it was a beautiful warm day I went and
installed a second antenna. It was days after that I went and turn
on the MeshAP.
The temperature change to -12 C and it started to
snow. Well winging it only got me into a worse situation. Here is
why. First the clear line of site wasn't that clear. Many trees
and telephone poles are in the way. Normally this isn't a big deal
but I also I notice a building near the Fresnel zone. I try to get back
on top of the roof to see but since it snowed, and it was too slippery
to chance.
So I took out my maps and photographs and will try to illustrate the
problem.
The Map shows the distance and 3 areas.
On The Map 1, 2, 3 are specific locations that corresponds
with photos below.
Distance is 1.37 Km. They are 200 mW radio cards on 8 dbi antenna.
Position 1 shows clear line of site
Position 2 also shows clear line of site
Position 3 there is a clear line of site unfortunately
there is no picture.
Looking with binoculars from the house towards top of
the building,
the only obstacles are a few deciduous trees (trees with leafs that
fall.)
To solve this problem will be working on 3 scenarios
- Change the configuration of the antennas to
direction with
15 degrees and 20 db
- Add amplifier on both antennas.
- Add an additional hop between these locations.
The Panoramic Shot of the Area Facing West-North to the Airport
(use horizontal scroll bar to view picture.)
The tip of the blue arrow is pointing to behind
some trees and beside
a large evergreen. Just a couple of notes the arrow should be pointing
about 1 cm to the left of the #3.
