The initial antenna design is done with eznec, which sets the basic antenna parameters. Over the past few years i have been using a hustler 6btv vertical antenna as my primary antenna for 80, 40, 30, 20, 15, and 10 meters. Online and downloadable dipole, inverted v and ground plane calculators. Describe your experience with the buckmaster 7 band, 300w, ocf dipole antenna and tell us why you give it the rating you did required. In all cases 15m and the warc bands will require a tuner. The radiowavz dx ocf windom is ideal for those of you who do not use a tower and beam. Acenterfeddipoleandcanbeconstructedasamulfbandantenna. The antenna calculator above uses this formula as a starting point to calculate wire lengths for the dipole. It is useful for measuring the cash margin that is generated by the organizations operations. The analysis is carried out by using programs which are available on the internet. Wanting to discuss ocfds and singlewirefed windom antennas. Its also ideal for those who want a high performance antenna with world class dx coverage 80, 40, 20, and 10 meters. Operating cash flow ocf is a common financial measure to determine whether the company is able to achieve the required cash flow to grow its operations. This page contains links to files submitted by manufacturers, along with a number of other antennamodeling files from various sources.
Just type in where it is resonant right now then type in where you would like it to be resonant and the spreadsheet will autocalculate the trimming. The adacceptance policy encourages manufacturers to allow arrl to make their files available for download. Buckmaster ocf antennas are made from the best quality materials and are designed to give you years of troublefree service. Buckmaster ocf antennas work mutiple bands and are made from the best. Here are some typical ocf dipoles that are successful designs 1606 meter ocf antenna layout using a double tuned stub for better 20 and 40 meter performance here is the 1606 meter swr graph using 200 feet of rg2 feed line and an average height above ground of 35 feet. Buckmaster dxocf40 antenna hf wire multiband, dxocf40. The offcenterfed dipole is a dipole whose feedpoint is at a point removed from the center of the antenna. Antenna modeling files american radio relay league. Courtesy of and designed by n2imf joseph r mielko this downloadable calculator will provide you with good starting measurements for a basic ground plane, inverted v or standard dipole antenna. This is a popular antenna design as the performance is very good across the hf bands and requires little or no tuning. The 4band antennas are ocf offcenterfed, with a 23 foot leg and a 45 foot leg, totalling 68 feet. Other useful information would include your experience with similar products, infomation on a product that you would purchase instead of this one, and so on. So my plan is to build a new ocf dipole using the new 4. Download hf dipole calculator 12 wave wire dipole antenna.
The antenna has worked very well for me, and i have worked much dx with it. An antenna that will operate well on all ham bands with minimal assist from the tuners included in many modern transceivers. The ocf fd4 fd3 windom antenna fd4 80402010 m the 4band fritzel model fd4 is a special version of a windom antenna. It has a nominal 3 db gain over an isotropic source and is directional, tending to. Feedpoint impedance of the antenna at that height on 80 will be about 3040 ohms before adding the 4 to 1 balun. Here are some typical ocf dipoles that are successful designs. Dipoles antennas are easy to build and can be very effective when placed half a wavelenth or more above ground. Tags antenna, calculator, download, electronic software, rf post navigation. This formula to obtain the length of a halfwave dipole antenna will give a. The 8band 300 watt antenna weighs 10 pounds and the 8band 3,000 watt antenna is 12 pounds. What i end up with is an ocf going down and away to the north from the tower.
Homemade carolina windom antenna m0ukd amateur radio blog. Off center fed ocf dipole antennas ham radio site home. It all started with the windom antenna windom antenna the windom was once a very popular multiband antenna. It is not imperative to feed the ocf antenna at the point shown. Distance from center of antenna to the center of the coil in feet must be less than half the total antenna length given above. Windom, w8gz who first published details of his antenna design in 1929. Please post a comment if you know other great software or links with information about antenna calculator and design programs. The modern common windom antenna is not an original singlewire fed windom, but rather an offcenterfed or ocf two wire feed dipole. Lets see some antenna calculator and antenna design software that will help you design faster and better. It is the underlying cause for the partial 80 m coverage and the complete absence of 30 mband coverage in prevalent ocf antenna designs. It is a halfwave long on the lowest frequency, and is fed from a coax cable. The windom is just a horizontal halfwave of wire on the lowest frequency of. After a lot of vacillation, i finally decided what antenna to put up.
Other useful information would include your experience with similar products, infomation on a product that. They are designed to give you years of troublefree service. Enter the desired operating frequency in megahertz to get a good starting length for a dipole in both feet and meters. A very basic program for calculating the length of each leg of a 12 wave wire dipole antenna. The first online dipole and inverted v calculator on the page below has been around. The radiowavz dx ocf windom is a off center fed ocf dipole antenna that exhibits outstanding performance on all bands. Whats the difference between these two ocf designs. Quick swr calculator for vertical and dipole ham radio. Our 4band antennas cover 40, 20, 10, and 6 meters, with no tuner required.
Heavy duty stainless 14 inch center threaded, cemented with lock nut eyebolt supports. The results are conveniently displayed in inches, centimeters, feet and meters. Buckmaster ocf dipole antennas buckmasters best coaxial cables antenna support rope antenna wire stringliner. 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.
Easy swr adjustment calculator for vertical and dipole ham radio antennas youtube. Building an offcenter fed ocf dipole loudoun amateur radio. Offcenterfed dipole antennas category is a curation of web resources on, ocf dipole, the six meter ocf sleeve dipole vertical, centerloaded offcenterfed dipole 6 band. This antenna was first conceived as a simple dual band antenna in 1988, in an attempt to achieve sensible dual band operation in a small garden of 14m 46 ft length. The measurements below are for building a simple dipole antenna. The normal windom is described as having a length leg, and a 23 length leg.
Off center fed dipole installed and written april, 2007. The antenna is designed to be fed with 50 or 75 ohm coax cable of most any length with a balun. Program good for 1 500 mhz, although intended for mf hf. Over the years i have spent a great deal of time getting things tuned as i want them, putting a large, 40 radials, radial field put in place, and getting the. It is an off centre fed dipole, with 10 feet of vertical radiator. A dipole is basically a length of conductor wire split into two portions and signal is taken off at the split. The 4band fritzel model fd4 is a special version of a windom antenna. In other words an 80meter windom 7 feet long would have one leg 45.
Hamcall callsign server hamcall advanced search dxspots hamcall dvdusbdownload gold membership hamcall database stats top callsigns on most wanted callsigns. Buckmaster ocf dipole antennas dxocf free shipping on. It is a halfwave long on the lowest frequency, and is fed from a coax cable through a transformer inserted in. Superb design no tuner, quality manufacture and booming all band signals. This article describes the characteristics of the windom antenna and shows the results of several simulations made with mmanagal, covering models optimized for the 20 m, 40 m and 80 m bands. Hamcall callsign server hamcall advanced search dxspots hamcall dvdusb download gold membership hamcall database stats top callsigns on most wanted. Download the ground plane dipoleinverted v calculator by n2imf.
The very predictable pattern of a resonant dipole applies only to the lowest, or design frequency, of the ocfd and the patterns for all bands above will be distorted. Ocf4010e3k ocf antenna windom this is an ocf dipole wire antenna also known as windom antenna fed at 19% from one end. A simple dipole antenna can be used for improved fm broadcast signals. It also works fine on all bands above 40m with a tuner, and even below 40m on 60m, and 80m, although the coax losses will be higher. For an 8010 meter ocf dipole antenna, divide the 1. Total length of antenna in feet open the dipole length calculator in a separate page. Above tables revealed that the resonant lengths of the 80 and 30 m bands are true outliers compared to the harmonic resonant lengths of the other hf bands.
The goal of the simulations is to check the behaviour of the antenna both in it fundamental band of design and in the harmonic bands, taking into account the impedance and the radiation. Electronics free delivery possible on eligible purchases. Last year on field day i was able to use an ocf dipole for the first time, and i enjoyed the quick bandswitching it allowed, so i thought id try and find a good ocf dipole for use while in the field. Antennas multiband antennas ocf dipole antenna windom.
Buckmaster ocf dipole antennas buckmasters best coaxial cables antenna support rope antenna wire stringliner reel. The list will grow with your help so lets start and share the knowledge. Thats one of the compromises that allows the ocf to have reasonable swr on the other bands. The bazooka worked well but was a single band antenna and i would replace it after any 160m contest with either a carolina windom or a 80m delta loop.
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