I originally posted here with a question about a system for my RV. Thorn directed onwards and was a big help.
Well, its been several months since Thorn started me on my search at wardrivingworld. Since then I've made several changes of direction and finally come up with the parts.
The Good is that I've bought the parts and got them all installed.
The Bad is that I haven't taken the RV to any area where there is a WIFI broadcast to test the parts.
And the UGLY is that I may just have exceed the power I need.
From what I have read here, that excess will increase "noise" and therefore degrade my connection, and it may even be illegal. I hope not.
Here's the parts I bought and installed in my Win XP system:
Adapter:
http://dplanet.biz/alfa.com/product_info.php?products_id=342
I'm hoping this will be compatible with Netstumbler.
Antenna:
http://www.wisp-router.com/itemdesc.asp?ic=VA24%2D16F&eq=&Tp=
Cabling:
Custom cable is 15 feet of ARC 240 cable. (Estimated cable loss 2 dBi, with two connectors)
Rotator:
http://www.durhamradio.com/s/product.php?productid=45118&cat=1867&page=1
So, I now can rotate the antenna from inside my RV and view the available signals using Netstumbler.
At least that is the plan. I won't actually know how this all works for a week or so, when I get the rig on the road.
Now, as to the power issues, I've used the SOM tool noted in the "barn" thread at
http://www.terabeam.com/support/calculations/som.php#calc
I have plugged in the data from my equipment spec sheets and guessed on the RX side as follows:
Distance between antennas .5 miles.
Rx Antenna Gain: 5 dBi
Rx cable loss : 2 dB
That produces a Theoretical System Operating Margin of 28.8.
Pretty close to 30, huh? If my guesses about the Rx levels are off, I could easily exceed 30 dB.
So, have I missed some important critical issue? What do you think about the setup?
And just to clarify for those of you who think I might be "camping", I'm not. I travel all summer long in the RV working very hard, and my wife and I value our Internet connections when we have time off, to stay in touch with our family, friends and clients.
So, I'd appreciate any suggestions or input you may have.
Thanks