Signal Lab

The Fall Checkup: Five Minutes That Save Your Winter

Every September the same thing happens: operators walk out to look over the antenna before the weather turns, and a few of them find something. This is the five-minute inspection that finds it first -- with a bench trick in the middle that most hams have never heard, and one thing to do before the inspection even starts.

Zero: Bring the Light Down, and Learn the Storm Rule

Before the checklist, the one change that lowers your risk more than anything on it. If a light rides the top of your pole, move it to the ground: a solar spot near the base, aimed up at the flag. Here is why, and it is physics, not preference. Anything at the tip of a pole in a storm is a sail on the longest lever arm the antenna has -- the wind load up there multiplies all the way down to the base, and the base is where poles give way. A light at the bottom lights the flag just as well, meets the Flag Code, and keeps the antenna inside its guarantee, which covers the pole as we build it and steps aside for anything added to it. Your pole, your call; we would rather you knew the trade before the wind does.

And the rule we are putting in front of every owner this fall, learned from a storm report that reached the bench this week: when the forecast turns, flag down, and nothing on top. Ten minutes at the pole saves a base section. For what it is worth, you are not imagining a rougher season: the count of billion-dollar severe storms across the country last year was among the highest in the 46-year record -- Climate Central keeps the tally -- and the reports reaching our bench this fall reflect it. Whatever the cause, that is the weather your antenna stands in.

One: Sight Down the Pole

Stand back thirty feet and look at the whole antenna against the sky. A pole that stood plumb in May and shows a lean in September is telling you where to look: almost always the base insulator. Fiberglass at the base carries the bending load of the entire pole in every gust, and a section that has started to give will show as a slight lean before it ever shows as a failure. Any lean at the insulator means replace it now, while the ground is soft and the wind is polite. Replacement base sections and insulators are on the shelf -- see the parts box below. If you own a tilt base, this is a ten-minute job on the ground. If you do not, it is still worth an afternoon.

Two: The Magnet Test

Here is the trick from our bench. Take a refrigerator magnet out to the antenna and touch it to every screw, bolt, and clamp you can reach. Real stainless hardware barely notices a magnet -- a faint tug at most. Zinc-plated steel grabs it hard. Hardware-store fasteners are often plated, and plated looks identical to stainless the day it is installed and looks like rust two winters later -- and the failure is not cosmetic: a corroded clamp screw is a joint that loosens under load. Any hardware that grabs the magnet gets replaced with stainless before the snow. The exact screw spec is published in our assembly documents so you can source it right, and the right way to swap it -- clean the joint, all loose then snug, how tight is tight, and the one never -- is written there too. Thirty seconds per joint settles a question no amount of squinting can.

Three: Re-Torque Every Joint

A season of wind is a season of vibration, and vibration loosens things. Go joint by joint, snug every clamp screw, and while your hand is there, wiggle the section above it. A joint that moves is a joint that will eventually let a section rotate, sag, or rattle in the wind. Tight joints keep the pole one piece of metal instead of several.

Four: Follow the Feedline

Start at the feedpoint and walk the coax to the shack. At the connector: is it tight, and is the weatherproofing intact, or has the tape lifted at the edge? Where the coax enters the ground or runs along it: is the jacket cracked or chewed? A jacket crack lets water into the braid, and water in the braid is loss you paid for with every watt. Walter Maxwell, W2DU, spent a book explaining that SWR is not efficiency -- a soaked feedline can read a perfectly civil SWR at the shack while eating your signal on the way out. Look at the coax, not just the meter. If a choke sits at the feedpoint, check that its connections are dry and tight; ferrite does not wear out, but connectors do.

Five: The Grounds and the Guys

Lightning protection is only as good as its bond. Check the ground rod clamp for corrosion and the strap for continuity -- a green crusty clamp protects nothing. If your antenna is a guyed model, check each line for chafe where it meets the collar, and snug the tension so the pole stands plumb without the lines singing. Dacron does not stretch much, but hardware creeps.

What the Bench Learned This Season

We run this inspection on our own antennas because the checkups our owners send us every fall teach us as much as they teach them. This year the lessons were clear enough to change how we build: base insulators from one source of fiberglass failed more than the physics said they should, and we moved our standard to a material that does not. And a storm took down a pole with a light riding the top, which is why item zero exists. That is how a hand-built shop is supposed to work -- the field reports, the bench listens, the next antenna is better. Your checkup is part of that loop. If you find something, tell us, and tell us what the wind did that day: every report goes into our log with the recorded gust, and that log is how the next antenna gets built stronger.

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73,
Jon KL2A
Greyline Performance -- Sun Valley, Idaho
435-200-4902