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Grounding standards for broadcast
There is no "free lunch" when we consider grounding. The height necessary to create a station footprint typically results in a tower being the tallest thing around. Thus, lightning strikes dramatically increase, hence the necessity of proper grounding.
While there are similarities between various grounding methodologies, asking 10 engineers for their opinions will probably return a minimum of eight different and valid recommendations. That being said, winding up with eight different recommendations may demonstrate a lack of standardization in grounding procedures.
Statistically speaking, no substantial increase in the quantity of actual lightning strikes over the past few years has been fully documented. Back when current technology was the BC-1G and the FM-25H3, electronic components used to construct broadcast equipment were not as susceptible to static as current items. The likelihood of destroying a vacuum tube or old-school transistor device by merely rubbing your hand across it was almost nil. Not so today. With current equipment, sometimes taking the item out of the bag incorrectly can result in destruction before it is even powered up. There's that free lunch again.
So while in all likelihood your facility is getting hit this decade just as often as it did when Ronald Reagan was President, it may seem like it is getting struck more often due to the vulnerability of equipment. Previously many strikes probably went unnoticed due to the more robust nature of electronics in this arena. Grounding of a facility, which in reality may have always been marginal at best, is now a very real spectre that must be addressed.
This realization has led to the development of several (not necessarily fully inclusive) standards in recent years. Most engineers probably have some degree of familiarity with Motorola's R56 standard as well as content in both Rev G of TIA/EIA 222 and the National Electrical Code. In addition, IEEE also has several different standards running the gamut of the scope of grounding. None of these standards taken together or individually will prevent a lightning strike; rather, they are intended to provide some guidelines and standardization so financial and operational losses are minimized.
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