Qorvus grounding

Single point grounding
Ground all electric equipment on a single one meter copper rod. With multiple grounding points, there is a difference in voltage at these points resulting a current surge when struck by lightning. Current flows due to a difference in voltage (V=ir or i = vroom - vkitchen/r)

Grounding
http://groups.google.com/group/qorvus-meshap/browse_frm/thread/647ac9f2457f375a#

'''The motherboard must be mounted on a metal plate and the metal plate earthed. This prevents static electric damage.''' As the fan blows air over the circuitry to prevent condensation, it builds up a static electric charge.

This is our annual reminder to double check that all your wireless installations, especially those on towers, have adequate in-line coaxial lightning / static protection and ethernet surge protection installed. THIS IS REALLY IMPORTANT IF YOU WANT A RELIABLE SYSTEM- THIS IS NOT A GOOD PLACE TO CHEAP OUT!

Lightning protection, which is a bit of a misnomer because it's really static protection, saves your Qnode receivers from the kind of damage that happens when static builds up on the antenna elements, and discharges through the radio. This can happen even when there's no lightning anywhere around, and can be caused by such things as cold, dry air blowing accross the elements and building up a charge. This is common in the winter, and in the summer in hot, dry climates.

The symptoms of receiver static damage can initially be subtle, you will see an increasing lack of sensitivity in the receiver and the links will show an ever-worsening rssi. Eventually the receiver will becoime completely numb and won't be able to establish a link. Data rates will slow to a crawl. Other times the radio card will simply die, or will appear to work from the software side, but no radio links can be established.

Ethernet surge protection and proper grounding of the case to an earth ground, are just as important for reliable operation. You should run 14 gauge stranded copper wire from the Qnode case down the pole or tower and to a copper-plated rod at least 3-6 feet into the ground near the tower, depending on your soil conditions. If you neglect these steps you can experience random failures of the motherboard, PoE spitters, and Compact Flash cards.

You can buy the needed items at a good price here:

http://www.wlanparts.com/category/surge_protection/

You will need the dc-6 Ghz version for 5 Ghz links, for 2.4 and 900 Mhz the less expensive dc-3 Ghz will work.

links
OutdoorBox, HardWare , MeshNetworking