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LIGHTNING STRIKES TO HEXBEAMS

Jan 3rd 2017, 22:30

NT0Y

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
Are there any significant numerous complaint rumors in ham radio land regarding any POSSIBLE high incident rate of lightning strikes to hexbeams (possibly due to the reflectors being ungrounded/floating)? Personally I prefer to have ALL antenna elements grounded when not in use as I have seen "St. Elmo's Fire" at sea on ungrounded antennas during lightning storms as well as ungrounded vertical CB antennas in Colorado exhibiting audible "hissing" just prior to a nearby lightning strike indicating high levels of static charge buildup. A.M. broadcasters see high static charge buildup on ungrounded A.M. broadcast antennas as well during lightning storms and those have "spark gaps" for discharge to ground. Years ago, it was rumored that a couple of very popular 11/10mtr fiberglass vertical antennas which had ungrounded radiators (only spark gap discharge and RF fed via a capacitor) which had (allegedly) high numbers of lightning incidents. I am preparing to put up a hexbeam and am sort of "polling" to see if anyone is aware of any serious issues of this nature with hexbeams? I PERSONALLY have heard of NONE and my similar "thread" on QRZ.COM has not revealed any issues thus far either.
Jan 4th 2017, 04:22

AA6E

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
The "hissing" noise is probably corona discharge. This will occur with a grounded conductor (especially with a sharp point like a lightning rod) when there is a high electrical field from an overhead cloud. I don't think there's anything you can do to attract or repel lighting by changing the conductors around (eg. grounding them). The main thing is to consider what will happen *when* you get struck or there is a nearby strike -- what path the current is going to take. You need good grounding at the base of the tower and preferably lightning arrestors (like Polyphasers) in your coax lines and rotator lines. (At the tower base is good, and possibly also at the entry to your house.) The hope is to direct the juice directly to ground ASAP, protecting your equipment and your house.

Effective lightning grounding is a tricky business. The typical amateur will try to do something that "looks right", but there is no simple way to know if you've done it properly until the big one comes. (And don't believe everything you read on the Internet!)

73 / GL Martin AA6E
Jan 4th 2017, 22:05

NT0Y

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
Thanks Glen/AA6E, but that was not my question. I am inquiring (polling perhaps) regarding any rumors/allegations of high numbers of lightning strikes occurring to hexbeam antennas. 73...

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