greyline, flagpole antenna, hf vertical, tubing, section,  4' extension, kit, ham radio, diy,
greyline, flagpole antenna, hf vertical, tubing, section, 4' extension, kit, ham radio, diy,

4' Extension Kit for HOA Flagpole and DX Vertical Antennas

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4’ Extension for DX Flagpole Antenna and DX Vertical Antennas 

Includes 4' upper section and the transition section (splice) with matching stainless hardware. 

You are working DX and would enjoy a little more height. We have you covered with our Extension Kit. Go higher, from 12' to 16', 16' to 20', or 20' to 24' and beyond.

Note this extension does not fit on the 28' design.

This 4' extension kit may add a little more punch and lower your angle of radiation on the horizon for that deeper DX, and just maybe more DX adventure goes into your logbook. You're welcome!

One famous DX'er reports going from 20-foot to 24-foot, that it is night and day. Others, might not notice as much. Physics is a mysterious process. Enjoy the experimenting at your QTH. 

This extension kit of aluminum tubing is cut, drilled, cleaned, polished, and prepared with care, for you. It will seamlessly match your existing vertical antenna by Greyline Performance. (Example: just below the top section of your flagpole or vertical)

As always, made of the very same Premium materials, Made in the USA, for your HOA DX Flagpole Antenna and GP HF Vertical Dipole Antenna. Another smart, rugged, and elegant ham radio antenna product.

More about Greyline Performance Antennas...

The Benefits of Greyline DX Antennas:

  • HOA Approved + XYL and neighborhood approved
  • No Radials! needed to achieve the high performance we stand behind
  • Premium-only materials: Double-dipped & double-walled aluminum, stainless steel parts, Made in the USA
  • All bands from 80-6M including WARC, MARS, etc. 
  • High-Power Standard (1500W) - McMaster Stainless Steel Hardware
  • Smart Design, Rugged Materials & Engineering: 80-100 MPH wind rating 
  • Best in Class Verticals are 'as good or better than any legacy brands you'll find on the market today
  • >90% and better efficiency across all bands
  • Very Low Losses owing to the feed system
  • Lower Angles than ground-mounted verticals without laying ground radials
  • Available sizes 12', 16', 20', 24' and 28' foot Flagpole Antennas & DX Verticals
  • Easy Install: Dig post hole, drop-in, plug in, play radio

XYL & fussy neighbors approve too. Why? 

Customer Reviews:

Bill works the world from his Home in an HOA!  

  • "XR0ZRC ... one-called him.  Not bad for a 20’ OCD and 100 watts."
  • "This Antenna hears far better than I ever expected it to!"
  • "Success running a few stations on 40 and 20 CW. I'm pleased with the results"
  • See Bill's DX Flagpole, here 

Steve A/B tests his 84' wire Zepp from his HOA

  • "A/B tested my stealth 84' end-fed and the DX Flagpole." 
  • "Lit up several USA and EU skimmers on 40/cw with the flagpole antenna."
  • “The EFLW also lit up skimmers but fewer in EU which gives an idea of the lower angle of radiation by the DX Flagpole."
  • “For DX, worked the XR0, C5DL, and 9G2HO on 40/30/20. I'm back into the weekly CWops sprints and have success running stations on 40 and 20 CW. I'm pleased with the results thus far."

Want to work the World like Bill and Steve from your home too? How well does your antenna play at your QTH?

What customers are saying:

  • "Highly Recommended for HOA and CC&R Restricted Ham Radio QTHs." 
  • "Got Indonesia (YB) this morning on 40m SSB with 100 watts. Just over 9,000 miles!"
  • "Smart, Efficiently Designed and Ruggedly Engineered Radio Antenna System!"
  • "Holds its own vs. taller competitors with no radials & is also stealth!"
  • "Equal or better performance than taller verticals requiring radials!"
  • "High power (1500W+) antenna and feed system are now standard!"

RF Blog

  • DX Flagpole, a passport to the Short-waves in Restricted and HOA Communities!
  • Nationwide HOA Approvals and Antenna Zoning For the Radio Amateur
  • OCF Vertical Dipole Mounting Scenarios Ground, Boats, Boat Docks, Bulkhead, Roof, & Towers
  • DX Flagpole Antenna, Customer Reviews, Pics, Audio, & RBN Signal Data  

  • A comparison of various Greyline Antenna heights:

    As always, when considering your grounding plans always follow the ARRL RF Guidelines. 


    Our Process and What to Expect
    More DX Flagpole History

    Ham Radio is fun again!

    Let’s get you and your friends back on the air! Your family and friends will appreciate the aesthetically pleasing demeanor and you will work the world from your home or HOA QTH.

    We enjoy talking radio: 

    Write in or call us to discuss any questions you have, we’re radio ops too! 

    It’s an honor to serve you in this manner. Thank you for the opportunity.

    73 Greyline Performance


    Customer Reviews

    Based on 3 reviews
    David Dobbins
    Great addition easy install

    Added this to my 20ft flagpole for 160 m work. Able to make contacts, looking forward to up the power. Great flagpole!

    Keith Tomas
    24' Flagpole does the job.

    I purchase a 20’ Flagpole antenna that also included the 4’ extension. I installed the flagpole the end of January here at my home in central Florida. The install was easy with only a couple of small issues that were easily resolved by just thinking things through. I installed the antenna in the back yard in the HOA and have not had any complaints.

    The performance of the antenna has been very good. The SWR on most band has been =< 1.5 except the 12 meter band. The SWR is just under 2.0. The DX into Europe and Africa has been good. Have done a lot of FT4 and FT8 with good reports. SSB has been good with good signal reports depending on propagation. All of my contacts have been made on 70 – 100 watts. I am using a SGC 230 tuner mounted at the base of the antenna

    Most of my contacts have been 10 MHz – 28 MHZ. I have done some work on 40 meters but not much. Not much of an night owl so I don’t get very much of a change to use the antenna on 40 – 160 meters. The SWR is on these bands is 1.0 – 1.3, so I would expect good performance if I had more power.

    At this point in time the only negative I have to report is the flag. It has been flying on most days in 5 to 15 MPH winds. I have taken it down when we had higher winds had exceed the 15 MHP. I noticed this morning the flag was torn and shredded. I took the flag down and noticed the flag was made by Anley and it was manufactured in China. I wouldn’t expect a flag to be in this condition after 3 months. I had USA made flags last over a year flying in much stronger winds that this one.

    I'm only giving a 4 because of the flag issue. I will reach out to Greyline to see what they have to say.

    We are so glad to hear that your Antenna has FB SWRs from 160-10M and congrats on the great DX! Fun... We buy our flags from several USA companies one of which is Anley, Inc., which is also a US company based in California. We are happy to replace the flag.

    US GOV reports 90-days is the expected Flag lifespan. 'The U.S. Government generally expects a nylon or cotton flag to last 90 days based on being flown daily from sunrise to sunset - but not during periods of inclement weather. Tests have shown that, in some cases, a flag flown 24 hours a day will last only one-fourth as long as one flown only during the daylight hours.' - again, happy to help and we will contact you directly for a replacement.

    Remember, Ham Radio is fun again, Please pass it on to your friends and family. - 73m Greyline Performance

    Bill Axelrod
    4 Ft flagpole extender

    Adding an additionial four feet radiating area to 20 ft antenna adds a statistically significant increase in total antenna efficiency. The antenna simply performs better. Glad I bought it.