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Coax Lightning Protection Basics

If you can't see the video, please insert this title URL into your browser search box:  This is post 2168 in a continuing series of simple ham radio antennas.

Thanks to for this concise, easy-to-understand tutorial on lightning protection for your antenna system.  You may want to store a copy of this video for future reference.

Here are the key points discussed in this video:

"You probably want lightning protection for you coax connection to your communication equipment. A lightning strike in the area can create a potential difference between the center conductor and the cable shielding which will transfer high voltage differential and damaging current flow through your equipment. This can destroy the expensive communication equipment. For a small price, you can install a lightning protector to protect your equipment. First let’s talk about the basics of what you look for when to select the right lightning protection for your application: 1-All lightning protectors have a frequency range that it will protect. With this lightning protector, it has a range of 698 MHz-2.7 GHz. 2-Connectors for in and out. The most common is N female on the input side and on the output side. They are available in various connectors like N female, N male, TNC, and more. In some cases, the lightning protector has a bi-directional flow so it is reversible. 3-DC Block vs DC Pass lightning protectors. -DC Pass is for applications that require power to be supplied to the tower by the antenna. This power is a lower voltage DC power allowed to pass through the center pin. -DC Block will not pass through any voltage through the center pin. Therefore, it will not allow power to be provide though the coax cable for powering equipment. 4-Technology type. Most coax lightning protectors use “Gas Tube” technology. We will explain the how the technology works in another video. - Gas Tube: - Is reliable for not allowing the surges to pass through and damage the equipment. -Does degrade over time depending on number and magnitude of surges. Typically, may last 5 years or a little more before need to replace it. -Problem is you don’t know when it has degraded and might fail. -Another problem is that the gas tube protector can get a static electricity build up that can discharge and damage your equipment. -Coil Inductor: -Coil inductor is a newer technology that also is an excellent protector of equipment from lightning surges or strikes. -Does not degrade over time and only fails with a direct or significant lightning strike so you know it is still good. -Does not get a static build up and release. -The coil inductor protectors typically cost 30-40% more but give us some significant advantages including: -Longer lasting lifetime protection or until you have a direct strike -Peace of mind they are still protecting our equipment over time -No worries about Static electricity build up and release Here are a couple of examples of the lightning protectors. Here we have Polyphaser brand protectors. We have the ISB-50LN-C2 which is gas tube technology and the TSX-NFF which is coil inductor technology. -Bulkhead Mount -Flange Mount Grounding when connection to metallic enclosure -Mfg. recommended additional grounding with 10-gauge ground wire from protector to ground. Connection to antenna and radio. Coax lighting protection is very important for protecting your sensitive and expensive communication equipment from all surges that affect the coax cable."
For the latest Amateur/Ham Radio news and information, please visit these websites: (breaking Amateur/Ham Radio News).

Thanks for joining us today.

Aloha es 73 de Russ (KH6JRM).


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