[MLB-WIRELESS] Fitzroy Tower update

[Drew]

>
>
>Problem 1:
>The tower is very high (15m+) - a 15m pigtail from aerial down to roof would
>be very expensive and very lossy.
>
15m is about 45 feet, and according to 
http://www.timesmicrowave.com/cgi-bin/calculate a run of LMR-400 would 
only lose 3db over that distance (or if you have a lot of spare cash, 
LMR-1700 only loses 0.8db). This solves a lot of your problems, and 
makes it a lot cheaper, and more flexible. If you stick with an AP, 
you're going to run into routing problems when the network gets larger, 
and that pesky thing about AP's not being able to speak to other AP's. 
If you run a linux box on the roof, and set everything IBSS (adhoc) you 
can customise the routing to your liking, and upgrade drivers/firmware 
much easier as they come out.

>
>Problem 4:
>Work out how to get the aerial / ap box up the tower (!)
>
there's always the fishing line + sinker + good aim + lots of luck 
solution. problem would be that you'd need to anchor the top and bottom 
to keep it from swaying, and the tower would create a lot of reflections 
if you hang it thru the middle or against the side. im sure we could 
come up with an engineering marvel to fix this though... like mouting 
the omni to a large plate of metal, and when you pull it up, the plate 
fits over the top of the tower, and then you just tie it down to the 
bottom to keep it from moving. then again, you could just hire a rigger ;)

another question is how much gain do you want on that omni? too low and 
it's not going to reach very far, but too high and you'll go over the 
heads of people nearby...

good luck :)
Drew



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