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Author Topic: How should I protect from device from static?  (Read 10153 times)

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AirNav Support

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How should I protect from device from static?
« on: June 01, 2009, 05:48:02 pm »
What is Static?

There are three types of grounds. In order of difficulty to achieve, they are from most to least: static; RF; and electrical. The methods and practices used to achieve each of these is different. Static grounding is the most difficult to do with guaranteed results, while electrical grounding is easy and can be considered to work perfectly in most cases. RF and electrical grounding is not important nor considered in this discussion for static discharge (lightning) safety.

The general rule on outside antennas is that they need to be grounded. There is no known government agency that recommends antennas not be grounded for safety. Indeed, the opposite is what is recommended and in most cases required by local codes. And, if you don't do this and don't care, maybe knowing that violation of these codes may be grounds for rendering your home owners insurance null and void in case of a fire caused by lightning strike.

Direct and secondary static electricity (lightning) strike has strike probability increased by a buildup of static charge at points of conductivity such as a metal mast or pole of an outdoor antenna. Static electricity is built up during a thunderstorm with wind blowing over the metal structures. This static charge builds and becomes an attractor to the opposite charge of static build up in the storm clouds. By draining off the static charge continuously, you reduce the probability of strike because the potential difference is reduced. It was shown in the studies conducted on the Empire State building that probability of a strike was a direct relation between the quantity of static buildup on conductive structures. Conductive structures with no ground path were at the highest risk while structures that were intensely grounded over several contact points were the least risk. This is because it is actually rather difficult to completely eliminate all corona point ( sharp pointed shaped geometry in the metal structure) static charge buildup even with "good" grounding on multiple contacts of the metal structure.

Continued at:
http://www.keohi.com/keohihdtv/hdreception/antenna_grounding.html


RadarBox

Firstly static damaging your RadarBox is an rare event. However the first batch of RadarBoxes (serials which do no start with ANRB1....) we experienced a return rate which while was still very low, we felt that we needed to improve the static protection further which was increased the newer batches.

Due to this any boxes of the first batch will be repaired if damaged by static for free regardless whether they are in the warranty period.

However regardless which batch version you have bought you should still take steps to decrease the chance of static damage:

If you looking for a permanent setup which is external, we advice the following steps:

- Purchase an antenna with an anti-static design
- Either attach a Mast amp which should bleed any excess static away and improve your reception.
- Either add a dc block (to bleed away excess static)
- Either our purchase Antenna Kit online which has an anti static design antenna and mast amp.

Those items above will reduce your chances of any damage by static to the max. Obviously you need take precautions during electrical storms to disconnect your antenna.

I use the standard antenna which came with the RB:

The antenna with the RadarBox is an indoor antenna but can be used for mobile events such as day trip to an airport. It will not last well against weather and also it doesn't have a anti-static design.

Static being built up in an indoor environment is very rare so we do not advise anything extra if your using it indoors. However again sensible precautions apply.