likely strike point and magnetic field source). The single point ground plate should also be oriented with its flat side parallel to the tower for the same reason.

In the equipment room, each piece of equipment must be bonded to the single point ground panel with a low inductance strap. This will maintain all chassis at the same potential during the strike event and minimize chassis-to-chassis current flow. The power, telephone and coax line protectors on each of the l/O’ s must be mounted on the single point plate. This will minimize l/Oto-l/O current flow.

Additional protectors may be used to protect the opposite side entrance locations for the power and telephone lines. These will provide added protection for jointly used equipment such as answering machines, appliances and etc. Ideally these should also be grounded and connected by a buried bare conductor to the ground system.

Remember that surge energy can enter your shack in either of two ways: from a strike down the road coming in on the power/telephone lines or from a strike to your tower. In either case. high quality protectors will dump the energy into the ground system. Because of varying propagation times, if the protectors are electrically spread out from each other, they cannot work in unison to keep the voltage levels between the equipment l/O’ s within a tolerable range for equipment survival.

Route all ground straps and grounding conductors so they have a gentle bending radius. Bends sharper than 8-inch radius will add unwanted inductance to the desired ground path. Even for conductors buried in the ground, try to prevent sharp bends.

Coax protectors should be units that have dc blocking on the center pin. This serves as a high pass filtering which prevents the lightning’ s low frequency energy from continuing to your equipment. The strike energy is picked off and diverted into the ground system in a controlled way. The dc blocking ensures the operation of the protector regardless of the input circuitry of the equipment.

Did you know that spark gap protectors with dc continuity will not work on receivers and shunt fed duplexers? This is not a well known fact. The shunt to ground inside a receiver (coil to ground for static draining) prevents the low frequency lightning energy from turning on the dc continuity protector. The coil shunts the energy to ground all right, but it is at the wrong place. If the coil can’ t handle the energy (half the coax surge energy is on the center pin), the coil will open up and the current will translate to a large open voltage source capable of arcing anywhere within the radio.

Lightning protection can be summed up simply: You have control of the lightning strike energy and not Mother Nature. Once control is lost, all can be lost.

The basement is the best location for the ham shack. It is closest to ground and will have the lowest inductance connection to the grounding system. Because it is below grade, some magnetic shielding may occur. Most basements have concrete floors. Since concrete is a conductor, your equipment must not sit directly on the

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