40-Foot HF Vertical in an HOA: Mike K7NT's Experimental Stack | Greyline

Greyline 20’ HF Vertical Antenna Extended to 40 Feet — Really?!
“I love the performance but have concerns. 40 feet is perhaps a bit long. I may shorten it to 36 feet.” MIKE K7NT — WASHINGTON STATE
As you may recall, we have run several polls recently to get into what you and our other customers really want to see built. We’ve asked questions such as How to Operate on 160M, How high can you go, Can you use Radials, How much power can you run, how much room do you have, and so on.
Quietly, we’ve been shipping out extensions to various customers to test adding 4 feet to their 20 or 24-foot Greyline Antennas — and some have gone up to 40 feet. Check this out:
Greyline 40-Foot HF Vertical Antenna in an HOA

Greyline free-standing antennas are engineered to 28 feet only. Extensions beyond this height require guys or tie-offs. These configurations are experimental until a fully engineered solution is complete. Not recommended for general use without proper support.
40’ HOA Flagpole Antenna with Guy Ropes

Guy ropes at 30 feet for a 40-footer make sense. There are calculators on the web for various pole and tower configurations — useful for determining attachment heights and guy angles for your specific setup.
Homebrew Tilt-Over Pivot Base for the 40’ Vertical
Our experimental field op told us that putting the 40-footer up solo was a bit iffy. He created a homebrew pivot point at the base of the vertical and slowly walked it up. You can see his handiwork here:

Mike K7NT reports that he’s working Real DX on 160-10M with this HOA vertical setup and is having fun again.
Mike is a serious contester building toward a full contest station — and is running the Greyline at his home station in the meantime. That says something about the antenna’s performance floor.
Want to Try the 4’ Extension?
Some of you may wish to experiment by adding 4’ extensions to your antenna. Let us know what you find — call or email. We want to know.
We hope you enjoyed this information and maybe learned something from it. Ham Radio is fun again! Pass it on…
What Customers Are Saying
- “Real DX 160-6M at my HOA”
- “4 Band DXCC in 3 months at my HOA.”
- “So pretty my XYL approves!”
- “If I can hear it, I can work it.”
At Greyline, it’s our Mission to serve you by offering higher-quality products that truly enhance your Ham Radio experiences. Standing up to Hurricanes is just a bonus. Antennas that work Real DX and that the ladies can love too. Now that is smarter, stronger, and more elegant for you and your family’s security. We are delighted to serve you.
Let’s enjoy the adventure, together. Until next time…
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73 Greyline Performance — 435-200-4902
Ham Radio is fun again! Pass it on…
