Since I have two brothers-in-law living line of sight, I thought I'd have a go on the 2.4GHz 802.11g scene. To make it interesting, I went for a vertical co-linear - just in case anybody else who can see me felt like hooking up.
So far I've learnt a lot but are yet to establish a reliable connection. Yea, there is magic involved in getting wireless connectivity to work. Lets talk about some stuff:
- Access Points (APs), the heart of the system. I have played with two types, the Linksys (Cisco) WAP54G and WRT54G. I chose these because they are Linux based and various aftermarket firmware, with cool features. On the WAP54Gs I am running the latest HyperWAP which amongst other things can increase the power output to 80mW. On the WRT54G I chose DD-WRT - unfortunately you can't run DD-WRT on the WAP54G because it doesn't have enough memory.
- I stuck a mast on the roof which is simple a 4m length of 40mm galv pipe, 2mm wall thickness, sourced from metal land, around $AUD40. It is bolted to a ceiling purlin (just above the ceiling) and then up to a rafter before popping out the roof for 2m of airtime. On the roof I used 2mm galv wire as stays - 3 running from some tabs I welded to the mast down to some tek screws I backed off from the tin. The concept is to have a really strong and stiff mast. Don't make the stays too tight, just pull them with pliers and twist them off. I made them *really* tight first, but the wind howls through and makes a racket in the house.
- A omni-directional vertical co-linear antenna, sourced from freenet antennas, takes care of the microwave end of the deal. Microwaves are polarised and funnily enough a vertical co-linear antenna is vertically polarised. Any recieving antenna must also thus be vertically polarised. Keep it in mind.
- The AP was mounted on a rafter just below the tin so I could get away with a 2m antenna cable. The shorter that cable the better to minimise cable losses, an important issue. This means you need a really long network and power cable but the losses there are inconsequential.
- Using the browser interface to the AP, set up the link. A "site survey" revealled quite a number of people nearby. Driving the neighbour with the laptop running Netstumbler reveals every 20th house at least has a wireless router. What I was interested in however is seeing my 3km distant brother in law.
- On the other end I went same deal mast with a Yagi antenna pointing towards my co-linear. With some Binoculars and a fair bit of looking around I spotted the vertical co-linear so we had line of site. Getting a stable connection however prooved to be very difficult, even at the lowest bitrate. I suspect we'd be better off with some directional conifers on both ends. I was going idealist however having omni-directional on my end - "for the greater good" - in case someone else wanter to hook up.
- After 6 months the vertical co-linear went dead. Pulling it down and checking it out revealed the connection had filled up with water...some silicone repair will stop that from happening again. Amazingly enough putting it back up minus water and we are away again.
- So if you live pretty much anywhere in Bulter, Jindalee, Merriwa or North
Quinns Rocks, and feel like popping up a little yagi/conifer pointed at me, then
North outlook.
