One exception is that you need wire that won't rust or corrode for obvious reasons. Plastic covering on wire used for a long wire antenna makes no difference. The type of wire makes very little or no noticeable difference at all at HF frequencies, so you can use anything so long as it can support it's own weight. So long as your tuner can be adjusted for a good match, this isn't a problem. Often the construction and length depend mostly on the specifics of the installation site such as availability of mounting points and available space, rather than an exact design.Īny antenna will work for receive, however for transmit the antenna system impedance needs to match that of the radio, otherwise you risk damaging your radio when transmitting. How well it works depends on a variety of factors related to the length of the antenna compared to the frequency of operation and the height. Generally, the longer and higher a long wire antenna is, the better it will work.Īny long wire of any construction and length will work to some degree. Many of the details you are asking about for a long wire antenna are not critical. Hope that helps - you could double check a possible length using MMANA/4NEC2 etc. The wire length has not been adjusted for a velocity factor.The Freqs I used are centered on the CW Sections.Non Resonant for HFAll bands 5.10m Possible When you run it - it would produce Non Resonant for Contest bands 5.10m Possible bands_contest = īands_warc = īand_length_in_m=] This is a small program to output possible non-harmonic wire lengths. I know this is asking a lot, sorry, but I would greatly appreciate the help, thanks!! What type and gauge of wire is best to use for the antenna? Can it be insulated to prevent rust? How do I do a ground or centerpoise? The tuner is supposed to be grounded, so do I put a ground rod into the dirt and run a wire down to it? Would that be a centerpoise?Ĭan I use the ground lug of an electrical outlet as a counterpoise?Ĭan I use a wire shorter than 71 feet for 80 meters effectively? The tuner manual seems to imply that I can use antennas less than 1/4 wavelength in length. If the end of the antenna has to go directly to the tuner, I'm concerned about a strain relief so the tuner mount point is not damaged. If I do 40 feet I can go between two points on the house (preferable because the house won't swing in the wind) but for 71 feet I would need to go to a tree on someone else's property (which I can do if need be).Ĭan I string the wire between two mounting points and use another, shorter wire from the tuner to the antenna wire? It could be very short, like a foot or so. This would rule out a 49 foot 2.5 inch (15m) length due to wanting to use 80 meters but allow 71 feet, although I may not have enough space. Further, consulting this link is helpful: The tuner manual says to avoid multiples of half wavelength as the radiating element, and says if I use a 15 meter wire I can operate all marine bands from 1.6 MHZ to 25 MHz. The tuner has a screw lug to connect the end of the long wire, but I'm concerned about connecting the wire directly to the tuner. This would give me 20 or more feet above ground. I can also mount the tuner there (it's designed for outdoor mounting). ![]() Fortunately there is a window that leads out to a roof and I can put a mounting hook into the side of the house. The radio needs to go on the second floor. The house is on a slab and all the plumbing is plastic. I would like to operate on 80 to 10 meters, although I'm not sure I have enough space for that. I live on a small lot with an HOA and based upon the layout it's best physically to use an end fed long / random wire. ![]() I need an antenna and don't want to spend much on a pricy indoor loop or the like, and I don't have an attic. Ultimately I may want this on my boat for WX data, GRIBs, email and so on, but before doing that I want to get it running at home and experiment with some data over HF. I have a ham license, but have been away from HF for many years and have never used a random wire antenna before. I recently picked up an Icom M802 marine HF radio that includes ham bands and an Icom AT-140 antenna tuner.
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