Good advice... but braid is good to wrap around things like the connectors on a 1/2" coax, then bring it down to a good grounding point. Kept short, it has the advantage of providing lots of surface contact to odd-shaped items like coax connectors. Better, of course, is to slice the insulation off and use the grounding kits--but anything done now is better than the perfect installation two days after lightning strikes..
These suggestions are designed for the non-engineer. In this day and age, many stations do not have full-time engineers, so I wouldn't want to suggest someone who is not technically inclined to disturb STL coaxes much, or try to get into AC panels.
Let's go back to my barn with the lightning rods. Usually they had thick copper cables going to ground rods from the lightning rods. Without attempting to be accurate on the physics, lightning is akin to what happens when you scuff your feet on the carpet then touch something metal. In this case it's clouds scuffing across the sky until a spark jumps to earth to something pointy. Hopefully it's something that has a good, broad electrical connection to the earth--not through something or someone that is not so conductive. So the better the path to ground--earth--dirt, the faster this charge is discharged without damage.
In my area I've found that the electrical ground at the meter is not necessarily very well installed, or much good for lightning protection. What you can do outside of course depends on your location and access to the earth (as opposed to concrete/asphalt, etc.). We have a "double-ought" copper cable from the panel box, along the back of the building and down to the power pole, and, going the other direction, to our tower, then down to several ground rods in the leach bed of the septic tank.
Even if you are in an old downtown (brick buildings, street in front, alley behind) a couple of ground rods along the back of the building tied together with heavy copper cable, then to a piece of copper strap into a back room someplace gives you better "earthing" (to use the more descriptive British term) than relying upon the single point electrical entry ground.
Let's take that small STL tower sitting on a concrete pad. You want a big wire or wide path to dirt. A piece of copper strap connected to the tower or tower base down to a couple of ground rods pounded into good dirt works well. Sometimes there is a base plate with bolts for the bottom piece of the tower you can slip the strap over, sometimes you need a copper grounding clamp to a lug on the tower, sometimes the best you can do is scrap any paint off, wrap the strap around a leg to get a good mechanical connection and use brass bolts.
Or take the antenna mounted on a pole on the peak of the building. You could nail strap to the side of building & use a flexible but heavy wire up to the metal pole. Or clamp heavy gauge copper wire (like #1, 2 or even "one ought" to the pipe and run down to the ground rods. There are methods that are OK, better and best--but something is better than nothing.
Inside the building: If you can, find a way to run a piece of copper strap from your outside ground rods inside the building. Then you can mount those grounding blocks for the TV cable coaxes, etc. on the strap--again, good mechanical connection. Polyphasor has been mentioned--those are good for things like you STL and RPU cables--you don't want to knock the station off the air, but make arrangements with the contract engineer, if you have one, to install them on that type of equipment. What we are doing is trying to keep the lightning out of the building in the first place.
Older buildings can be a problem--but if you can find a way to run either strap or just heavy copper wire into your rack room and between studios this can also help. There are various schemes people use--many use a "star" approach where everything comes back to a common point. Often near the panel box, but depends on how the building is built--if you can get that strap coming in through a wall into to a back room or closet and run everything to this common point it's a start. You don't have to bond this strap or heavy wire to everything, but often consoles come with a ground post (my R-55-E consoles do), and you can scrap the paint off metal racks and use some brass screws to make a good metal to metal connection to the strap or heavy grounding wires.
Electrical--(which should be left to an electrician if you don't feel qualified-but here's what to ask for). As some one pointed out above, the "third wire" ground is not always a good lightning ground.
You may have electrical runs in aluminum conduit, but sometimes there are points that are not bonded together, or there's a certain amount of corrosion that builds up. And lightning likes to be fast and direct--not wend it's way around though the building on the green wire. That's why it loves copper strap--a nice expressway to "earth."
What can get you, despite your attempts at lightning proofing, is static charges from lightning strikes to power poles that come in on you electrical wires or phone lines. Often when there is a lightning strike near-by there is an electromagnetic pulse that gets into long exposed wires, such as those hanging between wooden poles along the street... this induces surges into either phone or electric lines. Most phone companies install a "demarc" that includes surge protection against this--but you can buy these as well. And you can make sure their "demarc" has a ground wire tied to a good ground, not just wrapped around the nearest electrical conduit or using the ground plug on an outlet (been there, seen that). There are surge protectors that can be mounted in your panel box as well by your electrician.
Let's look at those CAT-5 cables strung through the attic. When we built our building we installed chicken wire up in the attic under the roof, and bonded it to our common ground. Not only keeps the RF out (combined site) but provides some protection against these EM pulses when lightning strikes the tower. Not easy to install in and old building--but putting your CAT-5 cables in something like electrical conduit (which is then connected to your common ground) or even flexible metal conduit might stop this kind of induced pulse damage.
Most of this stuff--copper (well they are steel counted with copper) ground rods, ground clamps for the rods, heavy cable, --can be purchase from an electrical supply house. Copper strap--try Georgia Copper to start (www.gacopper.com/) 2" medium thickness is a good balance point for price vs. effectiveness. Telco surge protectors: try Mike Sandman: www.sandman.com/
AC panel mount surge proctors are getting pricey--I've been getting the Leviton units available from http://www.tselectronic.com
Just some suggestions on what you might try.
These suggestions are designed for the non-engineer. In this day and age, many stations do not have full-time engineers, so I wouldn't want to suggest someone who is not technically inclined to disturb STL coaxes much, or try to get into AC panels.
Let's go back to my barn with the lightning rods. Usually they had thick copper cables going to ground rods from the lightning rods. Without attempting to be accurate on the physics, lightning is akin to what happens when you scuff your feet on the carpet then touch something metal. In this case it's clouds scuffing across the sky until a spark jumps to earth to something pointy. Hopefully it's something that has a good, broad electrical connection to the earth--not through something or someone that is not so conductive. So the better the path to ground--earth--dirt, the faster this charge is discharged without damage.
In my area I've found that the electrical ground at the meter is not necessarily very well installed, or much good for lightning protection. What you can do outside of course depends on your location and access to the earth (as opposed to concrete/asphalt, etc.). We have a "double-ought" copper cable from the panel box, along the back of the building and down to the power pole, and, going the other direction, to our tower, then down to several ground rods in the leach bed of the septic tank.
Even if you are in an old downtown (brick buildings, street in front, alley behind) a couple of ground rods along the back of the building tied together with heavy copper cable, then to a piece of copper strap into a back room someplace gives you better "earthing" (to use the more descriptive British term) than relying upon the single point electrical entry ground.
Let's take that small STL tower sitting on a concrete pad. You want a big wire or wide path to dirt. A piece of copper strap connected to the tower or tower base down to a couple of ground rods pounded into good dirt works well. Sometimes there is a base plate with bolts for the bottom piece of the tower you can slip the strap over, sometimes you need a copper grounding clamp to a lug on the tower, sometimes the best you can do is scrap any paint off, wrap the strap around a leg to get a good mechanical connection and use brass bolts.
Or take the antenna mounted on a pole on the peak of the building. You could nail strap to the side of building & use a flexible but heavy wire up to the metal pole. Or clamp heavy gauge copper wire (like #1, 2 or even "one ought" to the pipe and run down to the ground rods. There are methods that are OK, better and best--but something is better than nothing.
Inside the building: If you can, find a way to run a piece of copper strap from your outside ground rods inside the building. Then you can mount those grounding blocks for the TV cable coaxes, etc. on the strap--again, good mechanical connection. Polyphasor has been mentioned--those are good for things like you STL and RPU cables--you don't want to knock the station off the air, but make arrangements with the contract engineer, if you have one, to install them on that type of equipment. What we are doing is trying to keep the lightning out of the building in the first place.
Older buildings can be a problem--but if you can find a way to run either strap or just heavy copper wire into your rack room and between studios this can also help. There are various schemes people use--many use a "star" approach where everything comes back to a common point. Often near the panel box, but depends on how the building is built--if you can get that strap coming in through a wall into to a back room or closet and run everything to this common point it's a start. You don't have to bond this strap or heavy wire to everything, but often consoles come with a ground post (my R-55-E consoles do), and you can scrap the paint off metal racks and use some brass screws to make a good metal to metal connection to the strap or heavy grounding wires.
Electrical--(which should be left to an electrician if you don't feel qualified-but here's what to ask for). As some one pointed out above, the "third wire" ground is not always a good lightning ground.
You may have electrical runs in aluminum conduit, but sometimes there are points that are not bonded together, or there's a certain amount of corrosion that builds up. And lightning likes to be fast and direct--not wend it's way around though the building on the green wire. That's why it loves copper strap--a nice expressway to "earth."
What can get you, despite your attempts at lightning proofing, is static charges from lightning strikes to power poles that come in on you electrical wires or phone lines. Often when there is a lightning strike near-by there is an electromagnetic pulse that gets into long exposed wires, such as those hanging between wooden poles along the street... this induces surges into either phone or electric lines. Most phone companies install a "demarc" that includes surge protection against this--but you can buy these as well. And you can make sure their "demarc" has a ground wire tied to a good ground, not just wrapped around the nearest electrical conduit or using the ground plug on an outlet (been there, seen that). There are surge protectors that can be mounted in your panel box as well by your electrician.
Let's look at those CAT-5 cables strung through the attic. When we built our building we installed chicken wire up in the attic under the roof, and bonded it to our common ground. Not only keeps the RF out (combined site) but provides some protection against these EM pulses when lightning strikes the tower. Not easy to install in and old building--but putting your CAT-5 cables in something like electrical conduit (which is then connected to your common ground) or even flexible metal conduit might stop this kind of induced pulse damage.
Most of this stuff--copper (well they are steel counted with copper) ground rods, ground clamps for the rods, heavy cable, --can be purchase from an electrical supply house. Copper strap--try Georgia Copper to start (www.gacopper.com/) 2" medium thickness is a good balance point for price vs. effectiveness. Telco surge protectors: try Mike Sandman: www.sandman.com/
AC panel mount surge proctors are getting pricey--I've been getting the Leviton units available from http://www.tselectronic.com
Just some suggestions on what you might try.