Welcome to FlagpoleAntenna.com
Greyline Performance, LLC.
- DX Shipping to Europe / Australia prices listed. We help pay the bill on top of already Discounted Rates. Our gift to our International buyers this time of year!
- January 1, 2019: Added Lightning and Tuner protection products
- December 23, 2018: Added Remote Tuners to the website. Competitive Pricing, always brand new units with the famous warranties intact
- December 17, 2018: "Most vertical dipoles require the feed line to come off at a right angle for some distance. How do you avoid this?"
- December 6, 2018: "I have a QTH with another antenna, how does the DX Flagpole interact with other antennas?"
Note of Thanks to ARRAY SOLUTIONS! See Page 7 of QST?
Watch for the DX Flagpole and DXV line available through the always exciting team at Array Solutions in QST and NCJ magazines. Also, we've added premium products from their high-quality menu. Our thanks to Jay WX0B for his support!
What differentiates us from the rest?
Our DX Flagpole is a stealthy, no-radial-design that looks great in the garden and the HOA officials agree too because 'it's a real Flagpole.' Now fussy neighbors and your loved ones will be so pleased with your antenna choice. Imagine that! That's right, no more unsightly bristles and crossbars, matching boxes, coils and other bird-cage references that draw their attention as "that's obviously an antenna." It's a real Flagpole adhering to National Standards of Flagpole Regulations.
We also offer non-stealthy, non-flag versions too. We call these DXV. They are smooth yet rugged, very pretty aluminum just right for all band tuning and touring the bands! Listen carefully and you can already hear the SR Longpath DX coming through. See you on the air soon, I'm sure!
In any case, all of the OCF Vertical-Dipole lines of antennas are designed for high performance and high DX confidence, low angles, and low loss, for an agile approach to all band operations on one Stealth Antenna system!
Recap that... that is 10-bands between 80-6M (including WARC) with > 90% efficiency, and yes, the HOA's are approving this antenna because it's a real flagpole, that you can plug into your radio in case of emergency or for your enjoyment.
*The QRP guys love this antenna as their precious 5W actually makes it out into the propagation. What can you do with your low power, high-performance signal?
Our Challenge and Promise:
To offer you, our peers a smarter, stronger, more useful service. Please, challenge our findings and claims and let's have some fun getting you and your friends back on the air with real DX confidence!
- DX Flagpole (Stealth) Line of Vertical Dipoles: 12, 16, 20, and 28' footers. (No Radials!)
- DXV Vertical Dipoles: 12, 16, 20 and 28' (non-flag)
- Greyline Performance Antenna Arrays, coming soon!
Our Research Offering:
Currently, we offer our RF Research as an endeavor to provide a useful service to our peers. First up, the DX Flagpole Antenna (12, 16, 20 and 28' tall vertical-dipoles) and it's non-flag cousins, the DXV Vertical Dipoles, for those not needing the stealthy demeanor of a DX Flagpole.
Our OCF (off-center-fed) vertical-dipoles allow for the No Radials Required design. This means higher performance than the lossy ground radials and ground fed antennas!
Many have discovered that these are very real antennas that perform remarkably well when placed alongside the most popular vertical antennas on the market! Therefore we offer here Real Flagpoles that are also Real high-performance, all band antennas.
Learn more about the performance, structural and operational data of our antennas below and consider helping shape our story by engaging in discussions on our Blog and sharing these findings with your friends. They will be glad you did. Thank you, in advance!
You're going to like how loud you feel into DX with your friends on the bands with these multiband, no radials, vertical dipole antennas!
Q. Why FlagpoleAntenna.com / Greyline Performance, LLC.?
A. The Stealth, DX Flagpole Antenna is a very smart HF multiband solution from 80-6M that does NOT REQUIRE RADIALS. Designed to be installed in 1-2 hours by one person this antenna drops into a small post hole and doesn't require concrete. Work DX, keep the neighbors and your family happy and have comfort as it's engineered for performance and rated to 90-100 MPH. See the performance specs below. (Stealth DX Flagpole and non-flag OCF versions available)
We are Ham Radio enthusiasts, just like you! We have decades of experience in the amateur and professional antenna design sectors and a real interest to bring a higher-value menu of options to the hobby.
We enjoy solving complex communications system problems and intend to bring our peers more dBs per square inch by using 2018 Procomm technologies combined with smart design, quality materials, modern tech and decades of know-how.
Stay tuned for more products coming soon by joining our mailing list on the bottom right of our website. We won't share your email address. Thank you!
Have you seen our RF Blog? It is also a great way to learn more details about many of our FAQs.
Q. How does the Flagpole Antenna compare to other well-known antennas?
A. Let's compare our 20 and 28' versions with the Hy-gain AV-680 and Cushcraft R9:
The Red inner rings are 80M, blue 40M, green 20M, and orange 10M. You get the idea.
Look at the low angle in the OCFs and that extra punch. Yep, no radials needed!. Sure, you can use radials, of course, but not required for this performance!
Q. What's the difference between a 12' 16' and 20' DX Flagpole vs the very common 20' base-fed monopole with 16 buried radials?
A. We are surprised to find and report very little loss when dropping to the 16 and 12' foot designs. Look at 80 and 40M. Wow!
Now those of you in restricted areas can enjoy a little more confidence in working the DX!
One customer said, "Got Indonesia (YB) this morning on 40m SSB with 100 watts. Over 9,000 miles!"
Q. Regarding the 28' version. How do the 12' 16' 20' and 28' versions compare to each other?
The lower bands get a little boost when going to the 28' version and is the reason we offer it here. The 20' version works so well on its own and when stacked against the various market competitors.
With the push of a button, you are back on all bands, with ease!
Q. I hear 43-foot verticals with radials is a "sweet spot" but you guys promote a 20 and 28'er, what's the difference?
A. Bigger is not necessarily better! In this case, our DX Flagpole Antenna is less than half that height, does NOT need radials where the 43-foot vertical option does! Also, the OCF antennas enjoy a lower angle of radiation on many bands. (see graphic)
There's more... HOA's and CC&R's do not typically allow the 43' version but the 20' height is typically under most HOAs around the USA.
Now, look at the low bands! The DX Flagpole Antenna really shines compared to the radial dependent antennas, and yes, even the 43-foot vertical.
How would you like to get back on the air? Now you can have higher performance on all bands with a DX Flagpole that's also a stealth 80-6M antenna! Let's get you on the air with confidence! You'll sound amazing.
DESIGN + ENGINEERING
Q. Is the DX Flagpole Antenna Resonant or a non-resonant Antenna?
A. Ham radio enthusiasts generally expect an antenna to have a low SWR. Otherwise, they feel, “It won’t get out well and I might even damage my finals.” What’s your opinion? Is this a universal truth? Consider Resonant and Non-Resonant Mode Antennas. Here, look at this:
Here the antenna is operated at or near its natural resonant frequency. This is the mode most hams are familiar with. At the operating frequency, the feed impedance is close to 50 Ohms resistive and an antenna analyzer shows a resonant dip. An antenna operating in resonant mode can usually be fed with coax directly, without a matching network.
Here the antenna cannot be fed directly with coax at the operating frequency, for it shows neither an impedance of 50 Ohms nor a low SWR at the feed terminals. Some form of external matching is required for an antenna operating in a non-resonant mode. Frequently it is an antenna tuner. If you are contemplating, for example, a 20-foot, no-radial, OCF DX Flagpole Antenna, take special note... It almost always operates in a non-resonant mode.
Another, perhaps more familiar antenna that operates in the non-resonant mode most often is the popular 43 ft. vertical with radials. It is naturally resonant at 22.9 MHz, hence it does not show a low SWR or a 50 Ohm match on any ham band.
Therefore, do not attempt to feed a non-resonant mode antenna directly with coax. Some form of a matching system at the base is a requirement. Have you seen our DX Flagpole Antenna? :-)
Read more about this phenomenon on our RF Blog, here:
Q. Does the DX Flagpole require a balanced or unbalanced ATU tuner?
A. This reveals a common misconception about balanced/unbalanced antenna systems. In a practical sense, all that balanced means is that a source of RF voltage/current is not connected anywhere to a ground reference. Said in a simpler way, to be balanced an RF source must "float."
See our RF Blog to help for more information on this, here:
Q. What is the quality of the materials of the antenna?
A. We didn't cut any corners! Tubing is quality grade 6063-T832 aluminum, 2-inch OD to 3-inch OD top to bottom, thick fiberglass insulators at the feed and base, stainless hardware, Amphenol PL-259 connector for the pigtail, plus a 3KW custom Made in USA 1:1 Current Balun to help complete your "floating" antenna system!
Q. What is the wind rating of the Flagpole Antenna?
A. These antennas have been engineered to withstand 90-100 MPH wind gusts according to “Guide Specifications for Design of Metal Flagpoles,” ANSI/NAAMM FP 1001-07. This was used rather than ANSI/TIA-222-G (regulating antennas and towers) as this standard will be the one needed by building committees for structural analysis.
12-16' up to 100 MPH
20-28' up to 80 and 90 MPH
Q. You say Easy Install, Portable, and Quick-Deploy, can this also work as a permanent installation?
A. Yes, permanent quality is the idea! We offer the "portable" option for the instances where a required takedown is mandatory. This is common amongst our HOA operators. Therefore, we offer an easy drop-in and lift-out for those desiring this quick and easy removal before the arrival of stormy weather, for instance. That said, many choose concrete or "beefy" mounts and tilt-up options and those are great too. Your choice.
Again, we cut no corners using 6063-T832 aluminum, 2-inch to 3-inch OD top to bottom, thick fiberglass insulators at the feed and base, stainless hardware, and genuine Amphenol PL-259 connector for the pigtail, plus a 3KW custom Made in USA 1:1 Current Balun to help complete your "floating" antenna system!
Q. What recommendation do you have for Tilt-Mounts, Ground Mount, etc.?
DXEngineering offers a series of mounts and even still you have the lower stub to mount into the concrete. The jury is out yet on how aluminum does in direct-burials with concrete. Same as above, if the patio is poured, you need to look somewhere else.
Penninger Radio seems to be the way to go! They have a variety of mounting options: tripods, wall mounts, truck hitch mounts, and bolt to concrete mounts. Also, our engineer likes quality. Do you like quality? See their quality offerings, here.
Q. Where is the best place around my home to plant the Antenna?
A. For those in a neighborhood, we realize your selection is limited to your property. This antenna was designed as a smart match to please you and the neighbors. In the case of an HOA, we believe the locations with the widest view makes the most sense. Of course, on the side or corner allowable.
Q. What are my options for a base mount?
A. Our customers are using Tilt-Bases, Bulkhead concrete Mounts, and the included easy-install ground mount sleeve. Our products marry up with the popular sizes available in the market. If you need a pointer, let us know. Remember our 12, 16 and 20' OCFs are 2" OD, the 28'er is 2.25" OD.
Q. Concrete Recommendations?
So, unless you are a Professional Engineer matching this requirement, and/or we don't want to call on our alumni club referral program for a ground-mount savvy PE (it puts them in an awkward place) then we can proceed with a set of general rules of thumb, that may mimic the directions on the Quickcrete bag, that we see work repeatedly for low-risk structures such as the DX Flagpole and DXV's.
"If it were me, as an amateur radio installer, just winging it, I'd go down to Lowes, get the biggest Sonotube diameter they sell (12 inches or 18 inches), dig a hole about a foot deeper than the base section, add some gravel, and some Quickcrete. Dump the gravel in first, then put in the PVC. Stir the Quickcrete with as little water as possible (it cures stronger with less water). Then put the concrete around the PVC. Put a section of aluminum in the PVC, put a level on it, and be sure its plumb. You can tie out the aluminum 3 ways to support it while the concrete cures. Or you can skip the Sonotube and just dump the concrete straight into the dirt too."
A. Stay at least 3' away from the trees trunks and structures. We see tested examples of no more than 15' away from a structure as "in the clear" and that's specifically metal-siding homes! If your home isn't made of metal siding you are in the clear likely between 3' to 15' (see our Blog entry on this topic for more information on this one.)
Q. I'm retired and live alone in an HOA community, can I do this myself?
A. Yes! This is a strong yet lightweight antenna engineered to get you on the air on all bands in 1-2 hours and an easy install and take down, for one person. We realize some neighborhood rules along with common sense require the consideration to take the antenna down and therefore our DX Flagpoles and OCF verticals are an easy install and take down, again, for one person!
Q. "I have a QTH with another antenna, how does the DX Flagpole interact with other antennas?"
Vertical Antennas such as our OCF vertical-dipole designs have very little interaction with Yagi's on top of the tower as verticals and horizontal antennas generally ignore each other. To be fair, any antenna within a 1/4 wavelength of another antenna will interact at some level, of course depending on several factors, such as:
1. near the same frequency
2. of the same shape
3. facing the same direction and
4. in the same plane
Put an antenna designed for the same-frequencies near each other, yet in a null and it will be ignored. See our Blog for more information on this topic and others.
See our Blog for further insight on this topic and others, such as the OCF placement discussion. See "How close can I install the OCF DX Flagpole to my home?"
Q. What is the power rating of the DXFlagpoles and Vertical Dipoles?
A. The power limitation will be in your choice of a Tuner and Feedline from the shack and each units power rating. Some tuners are rated for low power at around 200W, others are 600W. We see a few options on the market in the 1500W+ range as well.
Keep in mind when using your antenna to observe all regulations and best practices regarding exposure to radio frequency emissions from any antenna. More information available at http://www.arrl.org/rf-
To mitigate your worry of RF exposure to curious hands, first, this type of vertical antenna offers that the lower area of the antenna is fairly low voltage depending on your power choice and is easy enough to guard against. As for extra comfort here, you can do what many have done and use a very thin layer of plastic insulation up to kid-reach height. Customers report using a simple sleeve for the vertical down low with a thin layer of insulation. Even the thinnest layer will be enough.
We've heard it said, "If it was my antenna and I was worried about it, I'd go buy some very thin wall 4" drain pipe and just sleeve the antenna, or even just tape it with a single layer of good electrical tape." Others install a reasonable fence, flower bed or other garden feature around the base making it more difficult for little hands to touch the antenna. Of course, those of you in an HOA may have aesthetic concerns that customize your approach. Take comfort that you have many options.
Q. Do you offer turnkey packages?
A. At the moment, we provide everything you need other than the tuner of your choice and your feedline to the shack.
Q. What comes with my antenna purchase? [updated 11.08.18]
A. We now provide a high-power balun and feed system with all of the OCF antennas as standard. You will only need to determine which remote tuner works best for you. There are many low power and a few high power options on the market. That said, we have tested the new DX Flagpole Antenna Line with several ATUs and all worked excellently from 80M through 6M. (some report using 160M too!) We recommend 'power over coax' outdoor remote tuners for mounting near at the antenna base. (see our Remote Tuner offerings today!)
Q. Do I need a tuner at the base of the Flagpole Antenna or can we tune from the shack with an ATU or Rig Tuner?
A. I'm glad you asked. Some people do tune the antenna from the shack and report happy results. Please keep in mind for the peak performance we showcase for this antenna, it is designed for a match at the base of the antenna. Typically, a tuner in the shack tunes the coax and the antenna and that's just not going to work well. Want a real high-performance antenna, a tuner must be installed at the base (as close as possible). Power over coax to a remote tuner is our recommendation for ease of use.
Q. Can you suggest any Lower Cost Alternatives to an Auto-tuner at the Base?
A. As we urge you to consider for best results, a matchbox or tuner located at the base of your DX Flagpole or Vertical-Dipole is not a luxury, it is essential.
Many users choose a commercial outdoor remote auto-tuner for the convenience of operation however, a purpose-built, relay switched matching assembly is also suitable. Other solutions are a fixed L and C matching network for single-frequency use. Another is a manual tuner enclosed in a weather-tight box.
Here are some less-than-optimum but workable substitutes for a base-mounted remote auto-tuner. (note: nothing beats a quality tuner at the base)
1.) Use a short run of 450 Ohm slotted window line from the antenna
all the way into the shack. It will require a 1:1 current balun in the shack. (note: not recommended for stealth operation)
2.) Use the DX Flagpole on only one band at a time with a discreet L/C matching network in an outdoor enclosure at the base. A parallel coil, series capacitor L-match will match the OCF antenna on all bands. Several remote fixed networks, relay switched, is also feasible.
3.) Use a manual tuner in an outdoor enclosure. Tune it up once on all bands and mark the scales for subsequent band changes. A second tuner in the shack or built into the rig will now safely bring the antenna to match.
4.) NOTE: A 4:1 or 9:1 current balun at the base is NOT an option. These will help the SWR on some bands but make it worse on others.
5.) Refer to the originally recommended Remote Tuners.
We've heard folks try these various techniques with favorable results. What's your method? We'd enjoy hearing your story.
Q. All bands, really? (11 if you count 160!)
A. Yes, 10 ham radio bands (MARS and Commercial sector bands too!) one little hole in the ground and ALL of our OCF antennas operate with an ATU at the base, as described, with good SWR across 80 to 6M. They are real antennas! Remember, it's the antenna system that makes this antenna work and the same applies for 160. It's a short antenna for 160 and will work if your tuner will take it there. We like to see our advantages on 80-6M and thus only advertise the performance measures on 10 bands,
Plan to try this on 160M? Let us know how it goes... we've heard stories of mobile antennas working real DX on Top Band. Remember the famous W7 who worked 160M from his Mobile regularly? This indeed is much better than that on 160M. My guess is it's better than a wet noodle and surely better than a 'cloud warmer' when installed as an antenna-system... you be the judge and please tell us what you see. Thank you!
Q. Most vertical dipoles require the feed line to come off at a right angle for some distance. How do you avoid this?
A. The 90-degree exit is required only when the feed line attaches from the side of the feedpoint. We exit the feedpoint coaxially down the inside of the bottom part of the antenna. This removes the problem of common-mode current induction with the sideways feed. Coaxial dipoles have always existed at the bottom where no common-mode current can be induced.
Q. Will this work in the FT8 mode?
A. This antenna is an excellent FT8 mode, all band antenna. With the ease of tuning from 80-6M including the WARC bands at a rapid rate, we see this being a natural fit for the FT8 WSJT-X 2.0 crowd. We hope you will give our antennas serious consideration.
DX Confidence on FT8 with one single pole for 10-bands, yep, it's that cool. Will you try FT8 this year?
Q. WARC bands?
A. Yes, all bands between 3.5 MHz through to 50 MHz. In fact, so far, our 12, 16, 20 and 28' version radiate very well from 3.5 to 50 MHz. See specs and plots for viewing references on angles and performance. 10 MHz, 18 MHz, and 24 MHz... no problem at all.
A smart, all WARC Bands Antenna that gets you back on the air in style.
Q. Does it come with a flag? How does the flag attach?
A. Yes, our DX Flagpole includes a USA Flag (or any other country flag) with your Stealthy DX Flagpole. Let us know what you would like.
We also include a cleat and pulley (truck) when you order the DXFlagpole that each simply attaches with a set screw, all within your shipment.
Of course, when you order the DXV version (non-flag) OCF vertical dipole, you will receive what appears to be a shiny, clean vertical antenna and not a Stealth DX Flagpole.
Q. How do you ship the DX Flagpole Antenna?
A. We ship the tubing and parts ready to assemble in a box approximately (5 feet x 8 inches x 8 inches) and a Weight of ~30 pounds based on your selection. (example: 36 pounds for the 28' footer)
Q. How much to Ship to Europe?
A. Example: Hamburg, Germany is$190 USD for one antenna, $300 for two 20' OCF Vertical Dipoles including value declarations. UPS International offers a 4-7 day transit at this price rate in many cases.
Q. How long does it take to assemble?
A. We can do it in 15 minutes but we have practice! We've heard reports of 1-2 hours from delivery to lighting up the coax with RF. It arrives ready to assemble. You dig a post hole, assemble, drop it in place, plug in your coax and you are On the Air. Take down is even quicker if done the way we suggest. Simply pull out the Flagpole and lay it down. It's designed this way so one person can do the job. Remember, safety first and have fun! In other words, don't wait for 100 MPH winds!
SOFTWARE + EXPERIENCE
Q. What software do you use for modeling?
We make extensive use of the EZNEC Pro/4 with NEC 4.2 calculation engine licensed by Lawrence Livermore National Laboratory plus various optimization programs (see NEC 2 note below)
Q. What’s the big deal about EZNEC PRO?
The NEC 2 calculation engine, which powers many amateur radio antenna modeling programs, is limited when modeling multi-band and complex antennas and can return inaccurate gain figures and other erroneous performance metrics that result in antennas that ‘that look. good on paper’ but disappoint in the real world. A seasoned designer would tell you, “Anyone can buy and use the software if they can afford it, it’s the operator with insight earned over decades in the field that arrives at the answers we find useful and even groundbreaking.” Watch for more groundbreaking with our team coming soon!
CUSTOM ANTENNA DESIGN
Q. I work for __________ and we need new custom RF and antenna systems designed for our commercial, broadcast, government, military, public safety application. Do you make antennas for the non-ham market?
A. Yes! We operate a custom RF communication and radio antenna design business. Our team has designed and built rugged, stealth and consumer level radio communications antenna systems for Milpro and Procomm clients for over 30 years. We really do enjoy solving extremely difficult, complex, RF and radio communication problems for the various government agencies, professional markets, and the global military applications. Industries needing RF expertise, such as Marine, Broadcast, Aerospace, and others have called upon us to secure two-way communication projects for over 30 years. What's your complex RF problem?
Contact our RF Research team through the contact form for more information. We can promptly engage your needs by email or an easy introductory call. Based in the USA, worldwide communication ready. Thank you!
Any questions or comments to help us move towards offering an even more useful service to our peers, we'd like to hear from you. Please contact us today.