Ocf vertical antenna. Let’s assume you want to focus on 80m and 40m CW.

Ocf vertical antenna. The versions described in this manual were assembled, installed and tested DX Engineering Multi-Band Off Center Fed Dipole Antenna Kits (OCF) take advantage of the practice of feeding two different length wire dipole legs with a 4:1 Balun. MFJ-1790 has a super low angle of radiation to focus your signal where you want it -- reduces QRM/Noise and gives great DX! Premium HF Vertical Dipole Antenna for 160-6M multiband radio operation. Greyline's HF Vertical Antenna for 160-6M, No Radials. To get gain you gotta lose gain somewhere. It will work well on the 80, 40, 20, 17, 12, and 10-meter ham bands with no need for tuning. com if you have any questions. ) It must be made of durable, high quality, weather worthy components. this 7-Band OCF Off Center Fed HF Dipole Antenna 1 KW PEP wire WORKS GREAT on the 7 bands advertised. The feed line routes into the lower half of the dipole up to the feed point. Building a 29 foot (8. This is the length of a standard dipole but instead of dividing the result in half, use a 36/64% offset to determine the feedpoint. The balun / feed point shall be installed on a 40 foot galvanized push-up steel Sep 3, 2025 · Fundamentals of Off-Center-Fed Dipoles Off-center-fed dipoles (OCFs) are 1/2-wavelength wire antennas fed at neither the center nor the end, but somewhere between--off-center The Six Meter OCF Sleeve Dipole Vertical A slightly different 6M antenna project by N1GY, an Off center fed antenna for the 50 MHz. No Radials, is smart. This type of antenna is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. NOTE – Signals will launch away from the 25’ 3” element. What is the best HF Antenna? High Frequency (HF) antennas are crucial for effective communication in amateur radio. Sep 12, 2025 · This off-center fed dipole antenna is ruggedly built with stainless steel hardware, 16 awg stranded copper wire, and is weather-resistant for outdoor use in permanent installations--- external hardware is stainless steel. 24' HF Vertical Antenna multiband, 160-6M. With improving band conditions in the future as we get into the next Sun Spot Cycle, a vertical makes a great DX antenna because of the low angle take-off of the signal. No Radials, OCF design for lower angle, low loss, low noise, high performance for Real DX plus the important NVIS pattern for disaster prep & emcomm. Along with critical length and height above ground the OCF is sensitive to anything in the surrounding area of the antenna. In more familiar terms, this antenna is off-center-fed (OCF). An HF vertical dipole for all frequencies 1. The end insulators are made from 3/8" round fiberglass. Greyline HOA Flagpole Antenna & HF Vertical Antennas for 160-6M. . Smith, W7ZZ Email: w7zz@arrl. It withstood over 100 mile and hour winds at my location without guys here in Colorado Rockies. , - should I expect an 80-10m End-Fed wire to send / receive different than a 80-10m Off Center Fed Dipole? The primary difference is feed point, end-fed @ 20 feet sloping upwards to 30 feet, then back down to 20 feet and the OCFD at fed at the middle around 30 feet and sloping to 20-10 feet on each end. If feeding the antenna up to a ratio of D1/D2 of 1/3 is more convenient to the shack, then do so. 8 meter) Off Center Fed Vertical antenna for HF ham radio #hamradioantenna #hamradio #portablehamradio The dipole Smartech 27OCFDV is part of the family of antennas with distributed power, also called OCF (Off Center Fed). Half-wavelength vertical dipoles, however, present two challenges of their own. It is rated to take 2 KW. Covering the 160-6M spectrum, our antennas deliver exceptional DX performance without the need for radials or guy wires. Free Shipping - Buckmaster OCF Dipole Antennas with qualifying orders of $99. Finally free of restrictive covenants and neighbors who failed to see the beauty in amateur radio antennas, I dreamed of building, for the first OCF Dipole Antenna Windom HF The Off-Center-Fed Dipole is a Dipole whose feedpoint is at a point removed from the center of the antenna. I have owned my Force 12 Flagpole antenna for 15 years and rely on it daily. For ham radio, disaster, & emergency communications. net is a Web site dedicated to ham radio (amateur radio). 1, 2 Here is why: Placing the feed point away from the center, increases the resistive part of the feed impedance and source load more than the reactive (imaginary) part of the resonant antenna, which is nearly resonant. Extremely robust construction in AW6063-T66 aluminum alloy and CNC machined parts from solid stock. First, the feed-point isn’t conveniently at the bottom as for a λ/4 vertical. 24-foot Flagpole Antenna. Routing the feed internally minimizes coupling of the feedline with the antenna. OCF antenna design. Smart design for XYL approval. HOA & XYL approved options. ". The more the load is unbalanced the more radiation you'll get from the feedline. But before we bend it, let us first take a look at the OCF vertical dipole in Figure 2. The balun enclosure is much smaller, 3" x 2" x 1". The base on these antennas is mounted about 10 feet off the ground in order to generate a low Oct 25, 2015 · A commercial antenna system, the Buckmaster 7-band OCF Dipole, exploits this property. Nov 15, 2018 · What I found was this little gem: a description of the vertical, off-center-fed, half-wave dipole antenna that he uses for portable operations: I use a variety of antenna systems. DX Flagpole Antenna and HF Vertical Antenna Multiband No Radials for 160-6M at home or HOA. Ham-made in USA from quality materials. This article Greyline Performance offers high-performance HF vertical antennas designed for ham radio enthusiasts, professional services, and emergency communications. 10–80-meter OCF Vertical Dipole Base HF Antenna. It's a dipole fed off center with a 4:1 current balun at the offset feedpoint. 28 ft. Greyline 12-foot DX Vertical Antenna, an OCF vertical dipole for all band HF radio operation. Crafted with premium materials and rigorous testing, these multi-band vertical antennas ensure reliable and efficient Feb 12, 2025 · eHam. Basics: Off-Center-Fed (OCF) Ground Plane Vertical Antenna (GPA) When the ground plane is parallel to the ground, a second way of matching coaxial cable is by feeding the antenna “Off-Center”. 28-foot HF Vertical Antenna for 160-6M. This freestanding OCF vertical dipole antenna is designed to provide 160-6M operation and is perfect for limited space applications. Shop Wire Antennas at DX Engineering. Free Shipping OCF 1⁄2 WL Commercial Trickery Crafty antenna designers came up with the vertical configuration of a 1⁄2 wl Off Center Fed (OCF) dipole making the short end of the dipole being an array of multiple, horizontal, 4 foot long metal rods – [Google-- Cushcraft R7 or R-8000 and Hy-Gain AV-640 or 680]. My feed line is RG-213 buried about 6" below the sod. Jan 6, 2018 · Off Center Fed Dipoles Fed With Ladder-Line By Cecil Moore, W5DXP, Rev. 1. Downside is that it needs to be up at least 35 feet. Here are key differences between these antennas, which focus on their Design, Performance, and Applications. Nov 16, 2024 · Having fun with an unconventional OCF Vertical Dipole Antenna #portablehamradio #hamradioantenna #hamradio Link to Michael’s channel KB9VBR Antennas:https:// With all things equal, radio, power, coax, direction, height, etc. For beginning, a simple vertical with a manually-adjusted coil at the base would be inexpensive and a decent antenna. Base HF antenna for 10-80 meters that is an off-center fed dipole type vertical and is pre-tuned for 9 bands that deploys in minutes. At the point before the coax enters my home, I wrap about 10 turns as a choke as per the The OCF dipole is a compromise design HF antenna which allows operation on several bands without using an antenna matching unit (ATU). XYL approved as Smart, Strong, Elegant. Apr 2, 2005 · An off center fed antenna is not a balanced antenna so I wouldn't feed it with twin lead. No Radials, OCF design is efficient & high performance, 160-6M. HF Vertical Antennas Design and Structure Apart from Alpha’s OCF This is the perfect companion antenna for a POTA activation or any field HF operation. Hence, the best installation for an OCF is a matter of convenience. Superior design delivers superior DX and NVIS performance with commanding customer care. , easy to put up/take down for DXpeditions or stealth. Sep 4, 2025 · ". Apr 21, 2021 · Whenever possible, run your coax an equal distance away from both legs of the OCF antenna as far as possible–don’t run it parallel to the antenna. Feb 3, 2023 · My typical OCF deployment uses a carbon-fiber mast as a center hoist. This type of antenna is designed for one principal amateur HF band, usually 80 meters or 40 meters, but typically displays VSWR minima on at least two higher bands, and can therefore be a good multi-band antenna. However, use parallel feedline and an ATU for all Jul 7, 2020 · The OCF or Off Center Fed Dipole antenna is much like a conventional dipole antenna in that the formula you use to calculate the length of it is the same. The antenna can be mounted as a dipole or inverted vee. Detailed assembly manual and serial Sep 24, 2020 · Vertical The basic quarter-wave vertical antenna is essentially half of a dipole with the other half of the antenna composed of radial s, either at or above ground. Supplied with high-quality 304 and 316 stainless steel fasteners for long rust-free operating life. To make an OCFD antenna work well on the higher bands, the resonant frequency must be placed at the bottom of the fundamental band, typically between 7. Sep 5, 2015 · Functional antennas are easy to build. This off-center fed dipole antenna is ruggedly built with 14 awg stranded copper wire,and is weather-resistant for outdoor use in permanent installations--- external hardware is stainless steel. These are wonderfully simple antennas that permit multiband operation with little or no tuning. It operates 40m-10m and everything in between. Unlike a coax-fed OCFD, the inability to install a common-mode choke at the antenna feedpoint may result in Jun 2, 2025 · Vertical multiband 1/4 λ Ground Plane base-fed antenna for the following HAM bands: 20, 17, 15 12, 10 and 6m. Ham Radio is fun again. This HF vertical is HOA and XYL approved, as Elegant. Reviews For: ZEROFIVE-ANTENNAS MULTIBAND VERTICAL DIPOLES Category: Antennas: HF: Verticals; Wire; Loop eMail Subscription Registered users are allowed to subscribe to specific review topics and receive eMail notifications when new reviews are posted. impedance “is easier for the tuner to cope with” across multiple bands which are related to even harmonic lengths of May 1, 2021 · A 40-meter off-center-fed dipole (OCFD) is a versatile antenna for portable operation or space-constrained fixed stations because it is a manageable length and can cover 40, 20, 15, 10, and 6 meters with low SWRs. It is complete, cut, tuned, and ready to hang. Works 4, 7, or 8 bands on one length of wire, with no tuner required! Built like a tank with high-quality materials. Design Parameters For an 80-10 meter OCF dipole antenna, divide the 1⁄2 wavelength standard of 468 by the lowest operating frequency of 3. Customer Reviews, feedback, and helpful Q&A for the Greyline Performance Flagpole & HF Vertical antenna systems. See full list on hamradiosecrets. Your friends, family, and DX totals will agree This 11-foot vertical lets you work all the DX you can handle! Features lightweight 11-foot radiator and two 6-foot radials both made of aluminum. 16-foot DX Vertical Antenna, an OCF vertical dipole for all band HF radio operation. Reviews For: Greyline Performance DXF Flagpole Verticals Category: Antennas: HF: Verticals; Wire; Loop eMail Subscription Registered users are allowed to subscribe to specific review topics and receive eMail notifications when new reviews are posted. Click on the link to connect to the product you need. Smarter, Stronger, & Elegant. OCF antennas are very convenient as they will allow multiple bands of operation with a simple wire antenna which is fed off center with a 4:1 OCF Current balun with built in feed line choke, The GigaParts DX Flagpole Antenna is an off center fed dipole. This is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. For a conventional antenna I would normally split this wire in half and place a feed point in the center. An OCF dipole uses the last 10’ of the feedline as a vertical resonator, so you get the benefits of a dipole with some vertical added in as well. Want to build a simple, efficient, multiband antenna? One of the best and inexpensive multiband antennas is the off-centre-fed (OCF) dipole. The change in antenna characteristics are very interesting in the Tall L-dipole form. Using that capability, Figure 4 below shows what happens to a Tall OCF dipole as the shorter lower arm is swung upwards in 15° increments from 0° (down), to 90° (horizontal), to 150° (60° up). Mar 2, 2009 · The Off Center Fed Dipole, (often abbreviated as OCF Dipole) is a simple multiband dipole antenna with good performance. The off-center fed dipole works well with most popular tuners to provide a good match across the most active HF amateur bands. We hear many queries such as, "how to feed the OCF antenna correctly?" and "Balanced or Unbalanced Tuner?" Read what we would recommend. It’s higher, though not necessarily exactly in the middle. Using EZNEC, the design of an OCF dipole allows many variations in overall antenna length, height and feed point to achieve the desired result. The most simple and effective solution to tackle RFI is placing a common mode choke. This is an OCF vertical half-wave that's 94% efficient, with a lower takeoff a The graph on the right from Antenna Theory & Design Vol 2 by HP Williams published by Pitman shows this variation for both vertical and horizontal dipole radiators. Contents0: One concern with making a multiband OCF dipole is achieving reasonable impedance on all amateur bands. Reviews For: Buckmaster 7 Band, 3KW, OCF Dipole Antenna Category: Antennas: HF: Verticals; Wire; Loop eMail Subscription Registered users are allowed to subscribe to specific review topics and receive eMail notifications when new reviews are posted. It is 133 feet long. As the feed-point is moved from the usual 50% vertical to 50% ground plane ratio, impedance rises. No Radials for Higher Performance, Lower Angles, Lower Noise and Lower Loss, for DX 160-6M. Among the best options are vertical antennas, dipole antennas, and magloop or magnetic loop antennas. Mar 1, 2023 · Introduction The POTA PERformer (Portable, Elevated, Resonant) is an elevated vertical antenna for 40M-6M sitting on a tripod (or an extended ground spike) with the feed point about 5-6’ off the ground and two elevated tuned radials. With a maximum height of only 20', it requires no radials, making it ideal for easy setup, yet still delivering optimum performance. For this pole, it’s roughly 20% from the bottom. This antenna is not meant to be used for a In this video, I talk about the advantages of Greg KJ6ER's Challenger Antenna. That is: 468 / Frequency Mhz will give you the overall length of the antenna. Questions? Contact us today, at 435-200-4902 Greyline 16-foot DX Flagpole Antenna, a real Flagpole approved for ham radio in HOA, smart design for Stealth, No Radials, OCF vertical antenna, a vertical dipole, for 160-6M Below, we'd like to show you why the HOA Flagpole Antenna is called a high-performance antenna system. 0 and 7. 8 - 50 MHz offer lower angles, lower loss, lower noise, >90% efficiency. 05 MHz. Nov 8, 2018 · Correctly Configuring the OCF Vertical-Dipole DXV or DX Flagpole Feed-System: Balun, ATU Remote Tuner, Radio Antenna. Real DX from home or HOA. Gain figures are decibels-isotropic (dBi) relative to a lossless antenna in free space. No Radials for Higher Performance, Lower Angles, Lower Noise and Lower Loss, for DX 80-6M. Suggested height is 35-70 feet. Ham Radio's Premium Flagpole Antenna and HF Vertical Antenna systems. Easy-to-Install: Installs in flat-top or inverted-Vset-up, feedblock has attachment points for tower or tree support. tall yet light weight. I think you'd be better off with the balun at the feedpoint and running coax. No Radials is Low angle, Low loss, Low noise, high-performance for ham radio, NVIS, disaster & emergency services. Man-Portable weight savings Normally my man-portable off-grid ops are either on the fat bike or hiking with the dog. The telescopic whip, te eHam. In fact, I use a 40M EFHW sloper at my home QTH in Silicon Valley. They are designed to give you years of trouble-free service! Buckmaster antennas are shipped fully assembled, ready to deploy with no tuning or trimming N3AFS Rating: 2021-02-18 Outstanding Antenna Time Owned: more than 12 months. One of the primary advantages of HF vertical antennas is that they are omnidirectional, meaning they transmit and receive in all directions. Keep antenna (and coax) away from house wiring including AC power, Cable/Satellite feeds, telephone lines as these wires can act as receive “antennas” and overload attached electronics OR these “antennas” can transmit spurious signals (and noise) to your antenna and coax giving a high noise floor. com We have complete OCF antennas and also the impedance transformers and chokes as separate products (see below for various options with and without vertical radiators). The cost of the mast and coax (my only purchased components) was less than many of the commercially-made OCF antennas found on the web. Antenna modeling software can optimize a vertical dipole into the tall OCF form. The OCF does work! Before we tackle the claims made about the OCF antenna, let's start by saying that it will work, but not significantly better than a dipole of the same length. It requires The OCF-3K80 is an off-center fed multi-band dipole. This is their re-designed vertical with very thick wall aluminum. The OCF dipole does require a balun. Note: It is not imperative to feed the OCF antenna at the point shown. As it is a dipole, no ground radials are needed. The OCF-3K80 is complete with a 4 to 1 Balun. No Radials. 0, 10/01/17 With the availability of balanced antenna tuners, more hams may be tempted to feed their Off Center Fed Dipoles (hereafter called OCFDs) with ladder-line or open-wire feedline to lower feedline losses. High input power, up to 3 kW continuous All-mode. Let’s assume you want to focus on 80m and 40m CW. Auto-segmentation is used where antenna arms are different lengths by Off Center Feed (OCF). The final antenna was almost two feet longer than the formula calculation (468/MHz). As frequency increases the length of the antenna and offset of the feedpoint become critical. No Radials is Low angle, Low loss, Low noise, low angle, for ham radio, NVIS, disaster prep, & emcomm. 45 feet on Dec 17, 2018 · OCF Vertical Dipoles (aka DX Flagpole Antennas) can be mounted on the ground at home or HOA, lake docks, saltwater beaches, sailboats and atop a tower. . 6 MHz and you arrive at an overall length of 130'. Radials are not needed for high-performance. Smarter, stronger, and more elegant all-band ham radio antenna option. net My quest for the ham radio equivalent of the “holy grail” – a truly broadband 80 meter dipole – began in the spring of 2008, when I moved into my new QTH on five wooded acres in a semi-rural area. What antennas are available? There are many: a length of wire with a tuner, a dipole (or inverted-vee) with traps, a vertical with traps, an 80m dipole with a tuner for 40m, a 40m dipole with a tuner for 80m, and probably a couple others. The legs are achored to the ground with tent stakes, or trees if available. OCF antennas are very convenient as they will allow multiple bands of operation with a simple wire antenna which is fed off center with a 4:1 OCF Current balun with built in feed line choke, OCF antennas are very convenient as they will allow multiple bands of operation with a simple wire antenna which is fed off center with a 4:1 OCF Current balun with built in feed line choke, The picture on the right above shows an OCF Dipole with the feedpoint positioned at the same feedpint of the classical WINDOM antenna, fed with 50 Ohm coax through a 4:1 or 6:1 balun at a point 1/3 of the distance from one end. In either situation, carrying capacity is always limited. It’s a dipole fed off center with a 4:1 balun at the offset feed point. It is a very effective multiband halfwave antenna that is ideal for home QTH installations with somewhat limited yard space because of its versatility of Design Goals and Objective: Construct a multi-band off-center-fed (OCF) dipole covering the 40, 20, 15, and 10 meters amateur radio bands, and possibly the 6 meter band (but that is considered a bonus band, outside the main project objective. If this is a multi-day excursion, shelter food, perhaps water, plus gear Find Buckmaster OCF Dipole Antennas and get Free Shipping on Most Orders Over $99 at DX Engineering! Buckmaster OCF Dipole Antennas are made from the best quality materials with a completely potted waterproof balun and no external connectors. The big advantage of this design is that you can make an antenna that does not require an antenna tuner by utilizing the constant impedance of the happy convergence that happens at 120 degrees. Where will you install yours? Increased ERP (Effective Radiated Power): The electrically balanced OCF dipole circuit of the system has an increased ERP over the base fed vertical (end-fed) antennas that use lossy matches to force low SWRs. You don’t have to spend mega $$$ to get a good antenna that works. It is an outstanding performer and has presented no problems. Sep 17, 2018 · Introducing DX Flagpole antenna, a 160-6M HF Vertical Dipole Recommended to anyone with HOA restrictions! Meet our latest product, the DX Flagpole Antenna, an off-center-fed (OCF VDA) vertical dipole antenna with a confident 160-6M performance. See Figure 2. Adding a vertical component can enhance performance by lowering the angle of radiation. The antenna Apr 30, 2023 · Notoir are the EndFed, vertical, dipole and its variants like the OCF dipole (Windom). Low Cost: Outperforms multi-band vertical antennas by a wide margin for an unbelievable fraction of the cost! Buckmaster OCF Dipole Antennas. It can be fed with standard 50-ohm coax. Weighs less than 3 lbs. But we’ll look at the off-center fed antenna, as it has the capability of working on two bands (and The “Micro Series” Off Center Fed antenna is made using #18 stranded insulated wire and a BNC for connection your coaxial cable. Douglas K. Please feel free to email us at alphaantenna@gmail. The GU4-HF-250-M balun, used on this antenna, uses the same cores that are used in the standard QRP OCF baluns. Why an Off-Center Fed (OCF) Halfwave Vertical Antenna One of the most popular halfwave antennas in ham radio over the past decade has been the end-fed halfwave (EFHW) antenna. 10-80 Meter V43 OCF Low Profile Vertical Antenna Operation This is a multiband system that allows the use of an external antenna tuner if it is installed over poor ground or not placed in a clear area. Mar 24, 2021 · However, any OCF dipole easily outperforms aforementioned obtrusive antenna arrangements. A backyard experiment with an off-centre vertical antenna suitable for operating from a place, like a crowded beach, where you can't have radials. Would the radiation Palomar antenna products include complete antenna systems, feed line chokes, feed line to antenna matching transformers, static bleeders and other accessories. I use it on 30, 20, 17 & 15 meters. From the Horizontal and Vertical L-dipole studies it is known that the far field radiation pattern around an L-antenna is not round. ajntmkp gpsu puxvjgv gdsbe mcer zgga jufuiw exygr fkyy eeub