In about 2006 ish Bill Messier K1MNW and the owner of Oak Hill Communications decided to play around with WiFi. Bill installed a 3' parabolic dish on his 2nd story deck at his place in Brunswick on Oak Hill. Bill's house sets up pretty high as he lives at the Oak Hill Tower site. By rotating the dish around bill was able to see many WiFi networks in the area.
One day I loaded a powered Linksys wireless router into a backpack and climbed my tower at my house while bill had his dish pointed in my direction. I had set the ssid to something I was sure bill would recognize but did not tell him what it was. As I neared the top bill read it off to me over the radio.
We then set out to create a permanent link between here and his place. The first attempt was with a WRT54GS Linksys router. We found this worked but not very well. Throughput was intermittent and poor. Our testing showed a link of only a few hundred KB per second. After playing with settings for a very long time we determined the link only worked consistently when the radio's were set to the lowest baud rates.
Along came Phoenix Contact and there new Industrial WiFi radio's. After hearing about my 13mile link they got us a set of radio's to try. To our amazement after setting up the radio's we were seeing throughput of ~ 7MB.
We now believe the Phoenix Contact industrial radio's had a some things we needed to make this link work well. First is they have a setting for link distance. This turns out to be very important as it tells the radio to compensate for propagation delay. The other is the filtering / shielding needed by industrial devices. Oak Hill in Brunswick is home to many transmitters including those used by public service, cell phone towers, radio stations, and commercial businesses. This creates a high RF environment and a challenge for any receiver. On my visits to Oak Hill its difficult to get my FOB to work to unlock my car doors due to interference from RF.
WiFi Link Map
Install Details
Both radio's are installed very near the parabolic dish antennas. 2.4G will not travel well in coax so we only have short jumpers getting from the radio's to the dishes. We send power / ethernet to the radio's via shielded Cat 5 cable. On the local side here the shielded Cat5 is ~ 200' long. The enclosures are not heated and it is likely we are not within specs for allowable temperature range however it has been many years in operation and is still working. The radio's never shut off so the heat generated internally may help keep the radio's working even in the extream cold weather we can het here in Maine.
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