Ideally for radials you should have them sloped downward at a 45 degree angle to help provide a better match. This calculator assumes nothing is in the way of the radio signal between the antenna and the. Antenna calculator and design software electroschematics. It is an unbalanced antenna, therefore compatible with coaxial transmission line without requiring a balun.
A simple ground plane antenna you can buildfor 146, 223 or 440 mhzin no time flat. Ground plan element dimensions for various local australian and some international amateur radio bands with 4nec2 an nec based antenna modelling and optimizing computer application the proposed 14. Feeding the antenna can be done at the director or at the reflector. Radial attach each radial with a 632 screw, lockwasher and nut 20. Maple leaf communications antenna calculator vertical. About vhf uhf ground plane antennas the resource is currently listed in in 2 categories. Use this online calculator to determine the length of a quarterwave antenna from the frequency. Calculate safety distance from your antenna icnirp is a calculator software that. Note that the quality of the other half of the antennathe conductive ground plane beneath itmakes a big difference in. Quarter wave antenna design calculator 50 ohm 14 wave antenna measurement. This calculator is designed to give the vertical length height of a quarter wave ground plane antenna, and the length of each of the four radials often called radiators for the frequency chosen. Use our simple calculator to determine approximate dimensions of materials needed to build a vertical antenna. Jul 16, 20 the ground plane antenna is omnidirectional.
The normal quarter wave ground plane antenna consists of a vertical radiator which is insulated and centered between 4 horizontal surrounding. There are usually four radials, three being a minimum, but you could use up to six. Enter the resonant frequency for the dipolevee antenna calculation. May give you some directionality due to being bike shaped but itll work.
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. Pin nose pliers, screw driver, marker, tape measure feet meters. The amountsize of the groundplane required for the optimal performance of a monopole antenna is determined by the frequency you are transmittingreceiving at. A monopole antenna is a class of radio antenna consisting of a straight rodshaped conductor, as well as other low frequency antennas such as the tantenna and umbrella antenna. Refer to the eznec online help for the complete text. In this case, its a multiband antenna the customer is using it can be used from 700 mhz 2700 mhz so the ground plane required could be anywhere from 464 square inches. Antenna design calculators calculate antenna element measurements for various antenna designs.
This calculator was adapted from the coilshortened dipole antenna calculator. Frequency calculations are based on radio waves traveling at the speed of light 299 792. Whats the difference between a dipole and a ground plane. Here, youll find links for antennas covering 30 mhz and up.
One fundamental fact about antenna radiation patterns and. Download the ground planedipoleinverted v calculator by n2imf. Dipole, inverted v and ground plane antenna calculators. How to build a ground plane antenna for vhf ham band. To use the calculator, simply type in your antenna height above ground in the appropriate window below and click the compute button. By on6mu lantenna 58 donda in vhf, le antenne piu usate sono le 14 londa e le 58 donda. Groundplane antennas for 144, 222 and 440mhz for the fm operator living in the primary coverage area of a repeate r, the ease of construction and low cost of a 14. The compliance distance formula gives conservative estimates for a number of vhf dipole, ground plane, and yagi antennas. If you have no particular preference within a given ham radio band, then simply enter its center frequency i. Ground currents all around the antenna make the image work. This calculator can be used to design a quarter wave ground plane antenna, with radials. Cubical quad antenna js calculator iw5edi simone hamradio. I have been making a few 14 wave antennas lately, mainly for uhf and the ghz bands with good success, so i decided to create a calculator to simplify the process and maybe get some people who have not tried one before to give it a go. Design and adjustement is easy, as with the capacitor you can tune the resonance by some mhz with no effort.
This is usually achieved with radials, either attached to the base of the vertical, or buried below a ground mounted antenna. A groundplane antenna is a variant of the dipole antenna, designed for use with an unbalanced feed line such as coaxial cable. For vhf and below, as the elements get bigger, some more structured design is needed. Thank you for all those questions, please keep them coming. This calculator is designed to give the vertical length height of a quarter wave ground plane antenna, and the length of each of the four radials.
For a dipole it is possible to look at both the along the axis of the antenna and also at right angles to it. This link is listed in our web site directory since wednesday sep 19 2012, and till today vhf uhf ground plane antennas has been followed for a total of 1972 times. It has advantages over your folded dipole in several important ways. Please practice handwashing and social distancing, and check out our resources for adapting to these times. You can alwys fine tune the antenna for best swr by sliding in or out the top tube of the antenna. Two diy dual band antennas i built for vhfuhf ham radio. Helical antennas invented by john kraus give a circular polarized wave. The image antenna just represents all of the currents induced in the ground all around the antenna. Here is a simple line of sight calculator that will do the complicated math for you to determine just how far the horizon is from your ht or your base station antenna at any height above level and flat ground or calm water on the vhfuhf ham bands. Another little application written to help aid in vertical antenna construction.
In verticals, something below must provide ground to complete the rf wave. But the construction details are important in order to efficiently convert directivity into gain. Spacing is the distance from the boom to the gammamatch. The main category is antennas for 2 meters band that is about antenna projects for 144 mhz. Amateur quarter wave ground plane antenna calculator. Radio waves behave very similar to the photons in light waves. In addition, specific models mentioned in the antennas forum at radioreference are linked here for future reference. It follows the fm convention of vertical polarization. Pay no attention to the wire goingoff horizontally from the base. Hf dipole antenna this antenna software will help you design a simple wire dipole. Vhf and uhf antenna systems 1821 fig23these drawings illustrate the dimensions for the 144mhz groundplane antenna. By way of background, a 58 wave antenna is the highest directivity, single element, linear antenna that you can construct. An omnidirectional folded dipole with a quarterwave j type matching stud.
This does not take into consideration the type or size of horizontal reflectors, of even if there is a need for them. At vhf and uhf frequencies the size of the ground plane needed is smaller. Vhf and uhf antenna systems 1821 fig23these drawings illustrate the dimensions for the 144mhz ground plane antenna. Dec 5, 2014 two diy dual band antenna s i built for vhf uhf. That image isnt an actual current or dipole at the position of the image antenna. You can further reduce the height of the antenna by placing a capacitance hat at the top. It was now time for some testing, i had joshi kaka to test the antenna with his antenna analyzer. Can also be used to transmit on murs or 2 meter bands. Before starting to build the antenna, you can stiffen. If youre a newcomer or old hat, or anywhere in between, when installing antennas, safety first. If you would rather calculate the length of a fullsize vertical antenna, see the quarterwave vertical antenna calculator.
Antenna design calculators category is a curation of 83 web resources on, parallel square conductor transmission line calculator, analysis of antenna mast strength and bending stress, full wave loop antenna calculator. It resembles a coaxial antenna whose lower section consists of straight elements called radials instead of a hollow conducting cylinder. Fortunately there is an antenna that is inexpensive and simple to build with a minimum amount of parts and tools. Find a tube with a circumference equal to one wavelength, and wrap wire in a helix spaced a quarter wavelength. It features wireend loops for safety sharp, straight wires are hazardous and convenience its top loop lets you hang it off high objects for best performance. This calculator is designed to give the vertical length height of a particular antenna, for the frequency and wavelength chosen. Note that the quality of the other half of the antennathe conductive ground plane beneath itmakes a big difference in both the efficiency and feedpoint impedance of the antenna. Download software 14 wave antenna with ground plane. Here is a simple antenna calculator for two popular forms of ham radio hf wire antennas.
Antenna efficiency calculator antenna efficiency calculator, parabola antenna antenna eirp calculator enter power, antenna type, frequency, coax type, coax lenght, press for eirp antenna gain vs height this calculator computes the gain and elevation angles for various. A ground plane antenna is a variant of the dipole antenna, designed for use with an unbalanced feed line such as coaxial cable. The radiation pattern shown on a polar diagram is taken to be that of the plane in which the diagram plot itself. The compliance distance formula gives conservative estimates for a. Quarter wave antenna design calculator jeroen steeman.
By on6mu l antenna 58 donda in vhf, le antenne piu usate sono le 14 londa e le 58 donda. Blog antenna ground plane calculation arcadian antenna. In addition, specific models mentioned in the antennas forum at radioreference are linked here for future reference if youre a newcomer or old hat, or anywhere in between, when installing antennas, safety first. Total calculator converte metriche inglesi americane. Paying attention to the effect of the ground plane, using the right materials and matching the impedance of the antenna to. Be sure your antenna length is measured up to 1,25 m. Do not use this software to determine whether an antenna is emitting an unsafe or hazardous level of energy. Though we made it for the ham bands, it was resonant at 9 mhz with the current length of its elements. Requiring a new 2 metre band antenna for local fm simplex and repeater communication and after evaluated a couple of the main contenders for the project i settled on the 5. Radial slowly twist the wire while pulling it to keep it taught. Ground plane for mobile vhf antenna i realize that the plastic i have chosen isnt the strongest option, but without a tire carrier its my only decent option i can think of.
Enter the frequency in mhz and click calculate it will give you the length for the radiating element as well as the ground plane elements. Homebrew vhfuhf ground plane antenna not to scale 20. A quarter wave monopole mounted against a perfect ground will have an. This antenna has no gain and requires a ground plane reflection to operate. With dipoles, one half of the antenna is your ground. Choose from quarterwave, halfwave, the powerful 58wave, 34wave, or fullwave, and calculate minimum lengths of required radials, and then shop for your needs on our other pages and select from our inventory of aluminum, fiberglass, wire, coax, connectors, and other parts and. Dec 5, 2014 two diy dual band antennas i built for vhfuhf. Mar 26, 2009 your bike unless its a very small miniscooter or pocket racer less than 30. Shrike hybrid minidiscone receives the commonly used frequencies in the 150, 450 and 800 mhz bands.
Radio line of sight calculator for use on vhfuhf ham bands. Normally these would be either vertical or horizontal planes. I dont want to use the tail light mount on the corner because, well, its on the corner and really low. A ground plane antenna project for 10 meters band by n4zaw. Note that the quality of the other half of the antenna the conductive ground plane beneath itmakes a big difference in both the efficiency and feedpoint impedance of the. Engineering calculator to find the dimensions lambda4 groundplane. Ground plane antennas are easy to recognize by their appearance. How to make a quarter wave vertical 2 meter ground plane antenna. Your bike unless its a very small miniscooter or pocket racer less than 30. If you run the simulation program mmana gal see the links list, design software, you will see that the 58 wavelength gives a nice 50 ohm resistance, requiring a series inductor to give a.
The horizontal radiation pattern is a circle where the antenna radiates equally well in all directions. The conductor width isnt of great importance in the design. Shrike vhf uhf triband ground plane used for receiving the commonly used frequencies in the vhf airband or 150 mhz bands plus the 450 and 850 mhz bands without requiring as much physical space as most other multiband scanner antennas. The resource is currently listed in in 2 categories. Its just one end of my g5rv dipole, or sometimes called a dummy load sorry just an old ham joke, hi hi. Today were going to build a simple ground plane for the vhf 2 meter band. The image antenna for a dipole over perfect earth is a dipole at the same distance below. When you found the sweat spot solder the the centre to the coil. In practice its best to make the antenna a little longer than the calculated value and then trim it to get the best swr value. With this our ground plane antenna for vhf ham bands was ready.
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