This post will show two variants of this antenna that can be used to receive 170. Remember, however, that the support should be grounded because the antenna acts as a lightning rod. This antenna was patented in 1909 by the german, hans beggerow. Paul, introduction to electromagnetic compatibility, 2nd ed. The jpole will take about an hour or so out of your day to build and tune, making a great antenna for a vhf base station. Design and analysis of dualband jpole antenna with variation in t.
Analysis of jpole antenna configurations for underwater. On most of the j pole designs out there, a choke should be used as close to the feedpoint of the antenna as possible to help prevent rf on the feedline and creating difficulty with swr readings. The sketch below shows its conceptual design from that patent document. Monopole is a type of the radio antenna formed by replacing.
The j antenna goes back many years, long before i became a ham. Modern antenna design, second edition, by thomas a. The polarization of an antenna refers to the orientation of. Categories antennas tags inductance, jpole, simulation, stub, uhf, vhf.
A few manual iterations produced suitable left and right distributions to. Its basically an endfed omnidirectional halfwave antenna, matched to the feedline by a quarter wave transmission line stub. However, with some improvements, the antenna can receive well both the uhf as well as vhfhi. For a 2 meter f 146 mhz jpole antenna, the 12 wavelength radiating section section a is equal to a 0. Polarization is important because the receiving antenna.
Wikipedia the j pole antenna is a popular antenna design among amateur radio operators because it is effective and easy to build. For best results make sure that the shorted part of the quarterwave feed section is above the support. We will use this wavelength equation for all of our calculations. True plumbers delight for 2 meters an all copper j pole. The jpole antenna s long and storied design history is due for one more chapter to mitigate the longstanding mast current and reliability issues. This antenna can be easily used for aresraces groups that spot antennas around for emergency use, since it requires little, if any, mainte nance during its lifetime. The grayhoverman antenna has been designed by doyt r. The zepp antenna received its name from its use on zeppelin airships. Meanwhile, the multilevel fast multipole algorithm mlfma is employed to. For 2 meters, the coil is 4 turns of coax at 5 inches in diameter. The buildup of opposite electric charge on both ends of the poles is where dipole the. The microstrip antenna designs usually suffer from a narrow impedance bandwidth. In this paper, a dual band jpole antenna for vhf and uhf transceiver radio communication was simulated and implemented. It is an implementation of one of the oldest antenna designs.
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