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One thing that wasn't mentioned is if you have a deep water well on your property, as many of us who live in the country do. If your outside BUD takes a hit and you have it grounded to a ground rod that hit is going down your well. That well casing is the largest, deepest grounding rod on the property. Ask me how I know. When mine took a hit the only damage to the system was to the Videocipher cartridge but the well pump was toast. Make sure your well circuit is properly protected to prevent backfeed into the house (GFI). Here's some reading from "Specifications for Lightning Protection — ASAE Engineering Practice." These are designed for farms and are not specifically laws but give a good insight into what's really involved, such as taking into consideration the type of ground and it's ability to disipate current. Much of what you read here has been incorporated into local codes so you may want to check with your local municipality.


"Grounding
Proper grounds are critical to assure dissipation of a lightning
discharge without damage. Extent of grounding will depend on the
character of the soil, ranging from two simple 10 foot grounds for
a small building located on deep conductive soil, to an elaborate
network of cables and rods or plates buried in soil that is dry or
rocky and of poor conductivity.
Minimum acceptable standard for each ground electrode shall be a
copper-clad steel rod at least 1/2 inch in diameter and 10 feet long.
Rods of solid copper 1/2 inch in diameter may be used in lieu of
copper-clad steel. Stainless steel ground rods are also acceptable
where acid soil conditions exist or other conditions warrant
substitution of stainless steel.
Wherever practicable, connections to ground electrodes shall be
made at points not less than one foot below grade and two feet out
from the foundation. Grounds shall be distributed and placed at
corners and other locations in a manner to direct the flow of
current out from the building rather than under it. Placing of
grounding under a building (as in extending a building) shall be
kept at a minimum. There shall be a ground at each down
conductor.
In moist clay, the ground shall extend vertically not less than 10
feet into the earth, and the earth shall be tamped along the full
length of the ground.
In shallow top soil where bedrock is near the surface, the lightning
conductor (extensions of the down conductors) shall be laid in
trenches extending away from the building. Trenches shall be at
least 12 feet long and one foot deep in clay soil, and at least 24 feet
long and 2 feet deep in sandy or gravelly soil.
In moist sandy or gravelly soil of ordinary soil depth, 2 electrodes
shall be driven at least 10 feet deep at each ground. The conductor
shall be extended out from the building in a trench at least 2 feet
from the wall. The two electrodes shall not be spaced more than 6
feet apart.
All underground metallic piping, including water piping, well
casings, sewer and septic lines, shall be connected to the grounding system with main size conductors and special fittings with a minimum contact surface to the pipe 1.5 inches long and 2 square inches area. Water pipe, well casings, sewer and septic line
connections are in addition to the required number of regular
grounds. If a metal water pipe, well casing, sewer or septic line
enters a building, at least one down conductor of the lightning
protection system shall be connected to it.
Lightning Arresters
Radio and television masts of metal, regardless of location on a
building, shall be bonded to the main conductor of the lightning
protection system with a main-size conductor and acceptable
fittings.
To protect radio or TV equipment against surges, a lightning
arrester shall be installed on the lead-in wire, tape or cable and
bonded to the lightning protection system directly or through a
common ground. Secondary service arresters shall be installed by
the lightning protection contractor, electrical contractor or the
electric utility company. Such arresters shall be installed on both
overhead and underground services at the electric service entrance,
or at the interior service entrance box, depending on local
regulations. Before installing a secondary service arrester, it should
be determined that the neutral wire is adequately grounded,
preferably to a metal water pipe system that enters the ground."

I was under the house yesterday and decided to inspect the panel box ground since this subject has come up. I know I do not have a bond wire between my dish ground rods and the panel box. So, I plan to add that soon. It's only a 25 ft run under the house so it shouldn't be too difficult. Need to pick up some #6 Copper at Home Depot today. I also noticed there is no bond wire under the house that bonds the service panel to the meter outside. This is about a 40 ft. run and as best I can tell it is only connected with the primary 200 amp service neutral. The meter box is grounded to its own ground wire / rod. I have about 3 volts floating on the neutral in the house at the Home theater and I wonder if not having the bond on the dish grounds has generated that. I always felt that was just inductance.

That 3 volts neutral-to-ground could just be a result of some (rather substantial?) current flowing through that branch. If the grounds in that branch run to the main panel, and you add the bond so that the ground strap in the panel is bonded to the entrance ground then you should be OK as far as grounding goes. But without both of the bonds you mentioned you have a risk of groundloops and the associated problems...

Thought this might help some

Hi everyone, just thought i would include a link to some very good grounding information, It's an article written by Mike Holt. Mike also has his own website and a National Electrical Code forum. I use it quite often in my electrical trade.

Installing radio and TV antenna systems <~ Grounding Article with visual aids.

Mike Holt's Forum - Powered by vBulletin <~ Mike Holts NEC Code Forum

I ran into a ground loop when I first installed my dish 12 years ago. I was a good boy and installed the ground block where the RG6 went into the house. When I got everything connected to my stereo, HMMMMMMMMMMM, I seem to have a bit of hum in my system. I found two things that I had to correct in my house:

1) Bonding the two ground rods. Since the rods were 25 feet apart, this was a no-brainer, but it involved trenching along the side of the house to lay in the #6 copper ground cable. Hum should be gone, but not quite.

2) In examining the electrical panel in the basement, I discovered a ground cable that ran to a copper 1/2" cold water pipe. I followed the cold water pipe back to where it came up from the meter and I found that a section had been replaced by PVC pipe by the original owner. There was no bonding between the copper segments, so the electrical box "ground" was based on the conductivity of the cold water in the PVC pipe. I fixed that with another #6 cable to connect the isolated cold water pipe to the 1" copper line that came out of the floor.

That squashed the ground loop once and for all.