Even in a very rural area one would be surprised at the amount of 'noise' in unlicenced bands which is what Lar is using. ( You do not need a wireless licence to use them)
The most common user of these frequencies is Wifi. People with Wifi may remember that the Wifi equipment was called 802.11B in the 00's then 802.11B/G later on and now 802.11B/G/N . 802.11B used frequencies aroudn 2400mhz and G added frequencies around 5300mhz to those while the N standard, around 2008, added the capability to use 2 or more channels. N is state of the art for now. WiGig 801.11AC will be the next version rolling out this year on the exact same frequencies. More noise is guaranteed.
The simple way to get more Wifi speed was to take on more channels, or larger channels and then 2 or more channels at the same time.
Consequently an operator, even in a rural area, has to carefully ask people to use certain WiFi channels inside their houses and NOT to use certain others.
This handy table > http://en.wikipedia.org/wiki/List_of_WLAN_channels when compared to Lars graphic above shows Lar is using kit with a frequency of 5180 to 5700 Mhz.
Therefore domestic wifi should not use channels 36 upwards and should stick to channels 1-11 which will not interfere with the outdoor gear.
If a specific channel is not selected in the Wifi Router/Hub settings in the home the device could hop from channel to channel trying to avoid interference but randomly causing interference while it does so.
A bit of order and everybody will find a happy co existence. It probably means that the Community WISP should configure the domestic wifi router as well as install the ISP gear on their installation visit.