W8JI's new Contesting and Boatanchor Room

This is a typical installation:

The most common place lightning hits is on the power lines. Lightning surges follow the drop to the house entrance (D), where a small portion of the surge is diverted to the entrance ground (C). The largest portion flows through the house wiring to the station equipment and out to the antenna (A) and station ground (B).

Good grounds installed at A and B actually increase current flowing through the house wiring and radio equipment.

If A is disconnected and B remains connected the radio is still in the lightning path from D to B.

The only solution to this problem is B has to be bonded to C with a much lower impedance path than the house wiring. B and C should always be bonded, this is even spelled out in the National Electrical Code.

"Common grounding is important to ensure an electrically continuous and uninterrupted path to properly dissipate lightning’s harmful electricity. Failure to make all of the required ground system interconnections is a common trouble spot cited in lightning protection system inspections."

My Station Ground

Workshop entrance and ground:

Receiving antenna, transmitting antenna, and control cable entrance at house:

Grounds and shields of all cables entering the house are grounded to wide copper flashing. The copper flashing connects to my station ground inside the house and to the utility company and circuit breaker panel ground. The perimeter of my house has a #6 solid copper ground wire that bonds to the water line, propane tank, TV antenna tower, satellite cable, and telephone and electric service ground rod.

This ensures everything in the house comes up at nearly the same rate during a lightning strike. Large lightning currents do not flow through the house.

House operating area entrance common point ground:

This is the receive antenna grounding block inside the house. Bottom cables are the entrance cables. This is an old picture; cables are now all F-6 with compression fittings. Transmitting cables go to a single point where an 8-position relay cross-over antenna switch routes cables and harmonic suppression filters to various radios. This switch allows any tower's grouped feedline or antenna feedline to be connected to any radio.

The transmitting antenna switch matrix is fairly complicated. I have three primary towers; a 160-foot rotating tower with antennas for 160 meters through 70cm, a 200-foot tower that provides a 160 meter omni vertical and an eight direction four square, and a 318-foot tower with multiple dipoles at various heights and directions for 160 and 80 meters. Each tower has a 5-position or 8-position antenna switch at the base. The 318-ft tower has an additional switch mounted 1/2 way up.

There are two additional 7/8th inch feeders out to areas for antenna experiments.

Feedlines are sized to keep loss below 1dB to any antenna feedpoint in the system.

Everything inside the radio room is grounded to the large copper flashing. This is additional assurance that everything in the radio room comes up at the same rate.

Despite this system having miles of coaxial cables spread over an area thousands of feet across, and despite all of these cables being connected 24 hours a day, I have never even lost as much as a computer modem or TV set in a storm! I have had a super-bolt melt the shield of heliax at my 318-ft tower base, but none of my radio, computer, or TV equipment in the house was damaged.

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