For Rod Speed: Example of Wi-Fi connection between two homes 5.4 km apart (3.4 miles)

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Hi Rod Speed,

Look at these WiFi signal strength values I just got when setting up a  
temporary Wi-Fi connection between two houses 5.4 kilometer (3.4 miles)  
away line of sight!
  <http://wetakepic.com/images/2017/11/01/wifi.jpg

And that's with known conductive obstructions in the primary Fresnel Zone!

You wanted to do something similar (with only one radio and only mobile  
devices and laptops in the house), where, in this case, my neighbor miles  
away called just now to say her Internet was down; so I said I'd set up a  
quick Wi-Fi network to "throw" her some of my Internet from over 3 miles  
away!

When I brought the radio to her house (about 15 miles away by road), I  
realized she didn't have an extension ladder for me to get on her roof, so  
I quickly hand bolted this spare Ubiquiti Rocket M2 radio to the top of a  
wooden stepladder in her back yard near enough to her house to run a POE  
injector Ethernet cable to it to power it up:
 <http://wetakepic.com/images/2017/11/01/wifi4.jpg

It won't hold up against a windstorm, but the quick setup worked perfectly!
 <http://wetakepic.com/images/2017/11/01/wifi3.jpg

Now she has Internet from me, where I'm miles away from her line of sight:
 <http://wetakepic.com/images/2017/11/01/wifi_2.jpg

Regarding your setup to throw some WiFi over to your neighbor only a few  
hundred feet away where she has a variety of mobile devices and laptops, it  
should be just as simple to set up (should take about 15 minutes if you  
have something to bolt it to).

Notice that we're using an *old* spare 2.4GHz Ubiquiti Rocket M2 radio,  
which is so old it has no other use, which costs about as much new as any  
decent home router does today.

Even though the Rocket M2 is an ancient radio, we're still getting -60  
decibels of Wi-Fi signal strength over the 5 kilometer distance, which is  
*great* signal strength for such a distance, given that it's on the ground  
level with obstructions in the primary Fresnel Zone and there's still a  
whopping 24 decibels *over* the noise level (of -84dBm).

The radio is capable of putting out 24 decibels (dBm) of transmit power  
into a 24 decibel (dBi) antenna, which is 48 decibels of EIRP.  

Try to get 48 decibels out of *any* home router for the same price, where  
the *best* home routers, last we checked (Buffalo brand?), were somewhere  
around 25 decibels to 28 decibels in toto (although I haven't checked  
recently) and where the most common home routers were somewhere around 18  
decibels to 20 decibels EIRP.

Given every 3 decibels is *twice* the power, the difference between the 20  
decibels EIRP (or so) of a good router and the 44 decibel EIRP (legal limit  
in the USA) here is immense.

I'm not sure what the legal limit is in Australia though, but generally the  
limit is high in the USA and lower for most other countries for some  
strange reason unknown to me.  

Anyway, I just wanted you to know that you can *easily* throw your WiFi  
over to your neighbor for all her iOS and Android devices to use, as long  
as you can *see* your neighbor, line of sight.

Good luck!

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