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You don't have to be in a thunderstorm to have a shocking experience with an antenna.
When I was an apprentice in a desolate place called Waiouru, we had a dipole strung up outside the workshop. It had the braid of the coax grounded and tapped onto the center wire of the coax was a spark plug with a 0.030" inch gap. (No metrics for me, so I'll let someone figure it out.) In the winter, when the snow clouds were down low, that spark plug was zapping away all day as it discharged the static electricity that had built up on the antenna.
We don't normally get the huge lightning strikes that they get in the USA, because our humidity is higher, so I suggest as a good starting point, you need to start reading some of the ARRL handbooks. Having a high wattage 100k ohm bleed resistor across the antenna to ground is a good start, but you need a fast DC (low resistance ) path to ground if there's any close lightning.
The best solution is not to have your radio connected to the antenna during a thunderstorm. That keeps the expensive item safe. Fixing an antenna or coax is a lot cheaper and simpler.
- Putting static discharge coils between mast-ground and the cores of the 2 dipole feedlines is a no-brainer.
- These presumably really should have some arc-gap or similar lightening protection too ...
- Feedline shield is grounded at the shack only (there is no mast)
- Feedline core is not currently protected at all
- The unun is on the house gable with no ready access to ground and whilst I can run a static discharge ground cable down the outside of the house, I suspect that running something sufficient to ground a lightning strike is less simple and aesthetically acceptable
I can 3D print Wire Winders which are ideal for lightweight QRP portable operation. I have attached a photos of the type that I recommend. The standard size is 250mm overall but I can make them smaller if required. The 250mm version weighs approx 30g.
The best wire to use is the really thin stuff, ( #534) from thewireman.com He is used to posting to NZ.
Steal a bit of knicker elastic to hold the wire on and you are away.
https://www.youtube.com/watch?v=o8RoYrmr8o8 shows them (about the 8 minute mark,) and a 1:1 balun, which can also be made.
These are printed in PLA which is fine for portable operation, but probably won't last forever if used in a permanent role. Some things that I have printed and left outside are still looking great more than a year down the track. Any random colour except brown or green, so that you can find them at a field deployment site.
Provided you wind on your wire in a figure 8 pattern, the great thing with these winders is that when you come to deploy the wire, you simply secure the loose end to the balun/unun or dipole centre piece, hold the winder through the round hole, and walk away letting the wire wobble off cleanly.
The biggest cost is the postage, which is $6 for an NZ Post bag. I can get six winders in the bag easily. These winders are priced at NZ$2.50 each which is basically covering costs.
Also, if you find something else on thingiverse.com that you'd like printed, email me.My email is firstname.lastname@example.org