Wednesday, July 15, 2015

More ProxyHam stuff

Somebody asked how my solution in the last post differed from the "ProxyGambit" solution. They missed my point. Just because I change the tires on the car doesn't mean I get credit for inventing or building the car. The same thing with this ProxyHam nonsense: nobody is "building a solution". Instead, we are all just using existing products the way they are intended. We are all just choosing a different mix of components.

People get all excited when they see a bare Raspberry Pi board, but the reality is that there's nothing interesting going on here, no more than lifting the hood/bonnet on your car. This is photograph from ProxyGambit:

What ProxyGambit is doing here is using cellular data on the far end rather stealing WiFi from Starbucks or the local library. Their solution looks fancy, but you can do the same thing with off-the-shelf devices for a lot cheaper. Here is the same solution with off-the-shelf products:

This is just a TL-WR703N ($26) router with a 3G USB dongle. You can get these dongles cheap off eBay used, or new for around $17. Combined, they are cheaper than a Raspberry PI. If you want to customize this, you can replace the firmware on the router with dd-wrt/OpenWRT Linux.

Like my solution, they chose Ubquiti's NanoStation. However, they went with the 2.4 GHz version (locoM2 for $49) rather than my choice of 900 MHz (locoM9 for $125). There's also a 5 GHz version one could choose from (locoM5 for $62).

The 900 MHz, 2.4 GHz, and 5 GHz are all unregulated ISM bands. They all require relatively direct line-of-sight. The 5 GHz band requires absolutely no obstructions -- you have to be able to see the other end of the connection with binoculars. The 2.4 band allows some light foliage to be in the way. The 900 MHz band is very forgiving, allowing heavy foliage and possibly a house in the way.

The upshot is that the difference between "ProxyGambit" and my solution is the use of a cellular modem on the far end rather than hitching a ride with Starbucks, and the choice of a 2.4 GHz for the long distance connection rather than 900 MHz. But don't be limited by these choices -- there is a huge range of choices that can be made here. ProxyGambit made some interesting choices -- give it a try yourself and make some different ones.

No comments: