Static electricity on antennas

Unfortunately not so the SOTAbeams SB5 which is a basic dipole and a coaxial choke. I’ve often seen sparking across the BNC on the cable end as it laid on the ground. Thankfully with a glass fibre pole and a plastic tube boom to the yagi, it is reasonably safe getting the antenna down… or at least has been to date! :joy:

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I have used kites and balloons at times and have used bleed resistors between the antenna end and the ground plane wires.

I recently had two experiences in high winds with a 20 m 1/4 wave vertical on an 11400 ft peak. Similar to yours. The clicking turned into a consistent low frequency snapping - about 5 to 10 times per sec. It caused the radio I was using ultimately to reset the microprocessor and lock up in an odd display state. Wind speeds were about 30 to 40 mph (60 kph or so) when a quick storm cloud moved overhead. A quick departure down slope was in order with the flash and sound of lightning some 8 seconds off, followed by freezing graupel / hail covering the trail. This convinced me that even my 16 ft vertical needs a bleed resistor. I am not sure about a ground stake. The radio recovered upon power up.

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I usually have a 4:1 transformer between the radio and the antenna. On the secondary (antenna) side, one end goes to the antenna and the other end goes to ground via a short spike (tent peg). That carries any static charge safely to ground. Having said that, if there is any sign of thunderstorm activity in the area I get down off the hill quick-smart. I don’t wait until there are nearby lightning strikes.

The most amazing static electricity effect I’ve ever seen was when I was at sea. My main HF antenna was a tall vertical with stubs on it in various places, looked a bit like a Christmas tree. One night, off the coast of west Africa, I got a panicked call from the bridge to come up quick. So I went, and the whole antenna was glowing blue. There was a faint buzzing sound and a strong smell of ozone. I checked and the antenna was actually earthed down in the radio room, that is, switched so it was directly connected to the ship’s steel superstructure, and through that to the sea. I left it alone! Sadly that was in the era before digital cameras… It would have made a spectacular photograph.

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I think that’s the best advice on here!

Obviously the ideal would be to not end up in that situation if you can help it but that is precisely what I did on the one & only occasion I found myself in that situation on a SOTA summit!

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Many years ago in rather wet/damp misty conditions during a winter traverse of the Seven Sisters in Argyle-shire in Scotland I heard this continuous hissing sound. At first I dismissed it as air escaping from my flask of hot coffee in my bag. However it continued for some time so I stopped and looked at my flask. It certainly was not coming from my flask and seemed to be from the rucksack & myself.

I can’t remember any easy escape routes off the mountain in bad WX so I had no other option than to continue and just hoped it was a small continuous static discharge.

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Two possible realizations of a simple but effective static bleeder resistor:

https://dl6ip.darc.de/kite%20antennae.html

http://www.ad5x.com/images/Articles/Static%20Bleed.pdf

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