Nextek, Inc.

A Layman's Guide to Choosing a Lightning Arrestor

Coaxial cables are often used for RF signal transmission in situations that significantly increase the risk of lightning energy and damage. Here we will touch on the most important parameters for the selection of a coaxial lightning protector; including, Radio Frequency (RF) performance, Arrestor Device Type protection capability, and construction materials.

RF Performance

Coaxial surge protectors are intended to pass through a desired RF signal with minimum loss or disturbance. When RF energy enters a protector, the energy is, in some combination, passed through, reflected back, and dissipated within the device. The fundamental RF performance parameters of a coaxial connector are RF frequency and the corresponding insertion loss and VSWR (or return loss). The loss of signal level through the protector is called Insertion Loss and is measured in decibels (dB). The reflection of a signal back to the source is measured as VSWR (or return loss) also in dB.

Rule: To minimize the impact of inserting surge protectors within the RF circuit, seek out products with the lowest Insertion Loss and lowest VSWR at the frequencies that you intend to operate.

Surge protection devices generally function by shorting the transient energy to ground or converting the surge to heat and dissipating it this way. NexTek arrestors mainly utilize shorting (or "crowbarring") technology due to the overwhelmingly powerful nature of lightning-related surge energy. It is important for these devices to be mounted and well-grounded near the coaxial cable entry point. This way, the surge energy is stripped off of the cable before it nears any people, equipment, or other items-of-value...and is simply given a direct path to the earth through the grounding connection.

Protection devices are more than insurance against equipment damage, they keep the danger outside. Only properly engineered designs, high quality materials, and certified manufacturing processes can produce products capable of withstanding the high surge currents, and that will not deteriorate over time (weather proofing is a key to protector longevity and RF performance).

Click to continue to Page 2: Device Type Capabilities

Nextek is the manufacturer of all the products listed in these pages. We are not a reseller or distributor.

Nextek Engineering designs only the highest quality devices: Poorly designed and manufactured devices can greatly reduce RF signal quality, be susceptible to weather elements, and fail to protect over time.

Be smart, don't settle for cheap protection of your valuable equipment.

Lightning protectors are also known as lightning arrestors, lightning suppressors, surge protectors, surge arrestors, and surge suppressors.

High Current Filters are also known as feedthrough filters, EMI filters, RFI filters, power filters, and low-pass filters.