49:1 unun wire lengthsfair housing conference 2022

Use a slide rule! x 4 in. Work all bands from 80 through 10 on it. My homemade 49:1 EFWH with a 60 wire (cut for 40M) would do just fine! endobj I will also find some sort of heat resistant packing material to help hold the transformer in place. We hoisted the free end of the antenna wire approximately 30 feet into a tree. He used 300 ohm twin-lead and a 4:1 UNUN, with a 1:1 current choke between the UNUN and the coax to the tuner and transceiver: The full-size "flimsy" (ref. If the transformer is used with an externaltuner in conjunction with a single wireantenna typically 130-135 feet in length, power should be reduced on those bands that show an SWR above 1.6 to2:5 withoutthe tuner. Weight: 0.380 lbs. random wire page. Here they are in order: endobj Best SWR was . The trick, therefore, is either are blocked out because an antenna should be at least that long. 3 to31 MHz - up to 1kW intermittent (50% duty cycle). I have used the 49.2 ft (15 Meter) length of wire on vacation with both automatic tuners and an MFJ Model 16010 tuner with good results for 40, 20, 17, and 15 Meter operation. A level of 500-600 watts is the maximum with a further reduction onany band measuringabove 3:1. So is an essential piece of gear to have. PVC Junction Box(Home Depot), 1 x 1/2 in. The free end of the untwisted portion of the long wire (past the 14th winding) will be secured to this bolt as well on the inside of the box, while the radiator will be secured to it on the outside. endobj var sc_invisible=1; Drill out holes in the designated bottom of the electrical junction box for the SO239 chassis mount. &nb good show chuck, you said ya picked up a 430, did i tell i fried the 0ne i got from you, can anyone point me in the direction of a 2 pill schem for the HG 2879? You can add your own wire or get the complete product from this link EFLW-3K antennas. Hope it's clear now, if not. Meet 'Balun One Nine', a small, cost-effective balun. wire lengths less than 1/4 wavelength of the lowest desired frequency This Balun Designs unit is replacing an MFj 1982 HP EFHW balun that was DOA when it arrived last May. (Center fed is so appealing because you avoid this.). . want the antenna to be at least 1/4 wavelength long for each band you 49:1 UNUN IMPEDANCE XFORMER FOR END FED HALF WAVE ANTENNA. Do what works best! I have not done this yet. , Most matching problems occur when the antenna system One is for the top of the box so that it can be hung up. Because I had some spare Cu-Wire I wound another 1:49 Unun on a smaller FT-140-43 toroid and tried different capacitors between feedline and ground (to compensate for the 10m band). Midi Music Power Handling (CW/SSB): 100 W/200 W Enclosure Width: 2.500 in. Jack, VE3EED - SK. So after much frustration..down it comes and you go on to a totally different type of antenna.all that time just wasted inyour opinion..until now! Wire-Lengths-for-9-1-ununs.pdf Created Date: 12/12/2022 11:20:42 AM . I used the RigExpert Zoom AA-55 to test VSWR of the 49:1 unun impedance transformer. 6 0 obj Antenna Design This type of antenna is very easy to install because there is no need . The "9:1 UNUN" are for random length wire antennas fed at the end. Many hams have tried till they are blue in the face to install the random wire antenna that works on most; if not all of the HF bands with terrible results. it is easy to pack and easy to install. Here Is a 250 Watt Home-Brew That I Made In about an Hour. You are using an out of date browser. 32.00. I connected the free untwisted end of the short wire to the center conductor of my homemade testing jig (see tools list) with an alligator clip. It is used for non-resonant verticals like 43 foot or 33 foot Or Wire antennas like an End-Fed 1/2 Wave Multiple Length Wire Antenna. Code Practice Experimenting by slightly changing the wire length (+ or-) is encouraged to provide best overall performance. endstream endobj startxref An end fed antenna consists of a wire fed on its end, the length of that wire is not resonant with any frequency or frequencies you will be using it on. unavailable, a random wire can save the day, but it is important to See the picture below. /ModDate (D:20221212112042) That type of wire antenna could be lower than 50 ohms at some frequencies and over 2,000 ohms at . Several ways exist to bring the wire's high impedance feedpoint closer to the desired 50 ohms, including use of a 49:1 or 64:1 unun, which eliminates the need . /Resources << hb```YloD@(aKI V!}g@~}%Q/[[~_=Wy-:O)x[~hs/~SGeG _QE C6q %r stream So for example 80m could range in length from 120 to 133 feet. Some of these numbers are too close to squeeze in between them. Gil Gruson 1 Campaign | Comines, France $0 USD 0 backers 0% of $3,450 Flexible Goal Follow Story FAQ Updates 0 Comments 0 Prototype The project team has a working demo, not the final product. (Also note that here may be instances where the suggested lengths may not work exactly due to the many variables in the surroundings of the antenna, wire length variances, your tuner, it's height above ground, it's construction, etc. 1 bolt for antenna hook up (with nuts, washers, lock washers, and possibly thumb screw; I used #8 diameter, about an inch or so in length.). presents an extremely high impedance to the tu /Type /Pages Dimensional Drawing of Standard Enclosure, 1:1 Common Mode Choke / Noise Suppression, Core Material Selecton for Baluns and Ununs, Antenna Matching Problems When Using Ladder Line or Open Wire Feedlines, Model 4932 - 4 & 9:1 Unun 1.5 - 54MHz - 2kW, Model 49130 - 49:1 - 80-10m EFHW - 200 watts, Model 64131e - 64:1 & 49:1 - 80-10m EFHW - Up to 1kW, Model 4116 - 4:1 Hybrid Balun 1.5 - 54MHz 3kW, Model 9130sw - QRP 9:1 Unun 1.5 - 54 MHz - 300 watts, Model 1115d - Max Choking 1:1 Balun, 1.5-54 MHz, 5kW. Typically unbalanced = 50/75 ohms too unbalanced = 450/675 ohms. Lengths for Long-wire Antennas Jack - VE3EED Recommended lengths: 29 - 35.5 - 41 - 58 - 71 - 84 - 107 - 119 - 148 - 203 - 347 - 407 - 423 Not recommended lengths: 16 - 19 - 22 - 26 - 32 - 33 - 38 - 44 - 46 - 48 - 52 - 64 - 65 - 66 - 76 stream So for 80 meters (say 3.525 MHz) this gives you about 133' of wire. 9:1 or 49:1 unun for end-fed long/random wire? <> /Type /Page End Fed Antennas. 80m up, W3EDP's 84' antenna, 17' counterpoise is probably the way to go. The popular End-Fed Half-Wave (EFHW) Antenna is an easily portable, high-impedance (2,000-4,000 ohm) wire antenna that resonates on its fundamental frequency and all harmonics above. I imported my spools from the US, but I have seen them on Ebay in the UK. An Unun is used to match an unbalanced line to another unbalanced line. IMG_2.jpg Step 2: Take the 6 feet of 18 gauge enameled copper wire, measure 11" from one end and fold it back. Anyway, an old friend mentioned 'MyAntenna.com' but they were closed for the summer. I made just a touch over 100 QSOs today with the new unit. A small ring terminal for 14ga wire that fits these screws would be helpful too. Alternate connectors and Mounting Options are available in the. (Originally published February 22, 2021). endobj for your country and favorite modes of operation. well, the main antenna wire goes to the 9:1 UnUn "+" connector, the vertical counterpoise (insulated !) so that it is not a halfwave multiple of any frequency you want to use. 2 eyehooks with washers and nuts (I used #8 diameter, but size is up to you.) I connected it to a 33 wire running from my balcony, through the trees, and ran WSPR overnight to check things out. Support The Site /Contents 5 0 R often can't match it. This transformer converts the impedance at the end . ones HF & Shortwave SO-239 connectors are silver plated with Teflon insulation. Ham Radio News! Any SWR measurement taken with the transformer at the feedpoint should not exceed 1.5:1withNOtuner in use. rig, often with no feedline, and the other end in the air attached to To DB's point of a single band antenna, this 49:1 transformer is a good choice for a single band matcher. 0$Ve 31 Contact =======================, More on Random Wire Lengths from Mike, AB3AP (06-29-2012), I was surfing around Hamuniverse.com and found thIs page on random wire antennas: >> VSWR analysis of the antenna in the field showed that VSWRs between 3-5.5 from 40M to 10M. Care to buy us a beer? Well then you need to choose a wire length that is at least 1/4 on 40 meters, and doesn't fall on any of the 1/2 multiples for ALL the bands between 40 to 10 meters While you could certainly calculate the lengths to avoid using the standard formulas, and then make a chart, the section below may be what you are looking for. The unun was floating at about 15 feet above ground. We are working every day to make sure our community is the best Radio Hobbyist's site. For reasons that I do not understand, adding a capacitor between the coax conductor wire (untwisted free end of short wire) and the ground (twisted free ends of long and short wire) can increase the functional bandwidth of the antenna on the higher HF frequencies. . Designed for those who want the maximum isolation and choking across the full HF spectrum. <>/ExtGState<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 612 792] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> There are so many new frequencies to stay away from, that it gets pretty tricky for the longer wires. Building on the original 1:1 design by Dr. Jerry Sevick, this balun has two (2) cores in a stacked Model 49131 - 49:1 - 80-10m EFHW - Up to 1kW, Decrease Quantity of Model 49131 - 49:1 - 80-10m EFHW - Up to 1kW, Increase Quantity of Model 49131 - 49:1 - 80-10m EFHW - Up to 1kW. bands you're intested in in a vector like the example below, by typing. JC[ d8O[UKKQ{yZ{G 'Upno_*~8uo a@G`' zxUHXW&`}mEp`?i0 oE:N0-/t"t.-? I have included a screenshot showing the stations that reported spotting my 200 mw beacon over the last 16 hours. wire is at least 1/4 wavelength. Q https://elginradio.wordpress.com/2017/10/17/end-fed-half-wave-antennas/. This transformer is designed to be used with an end fed half wavelength of wire only. This project assembles a 49:1 ferrite-core ("FT") type #43 transformer that matches 50 ohm input to 2500 ohm end fed antenna. It is used fornon-resonant verticals like 43 foot or 33 foot Or Wire antennas like an End-Fed1/2 Wave Multiple Length Wire Antenna. Designed for use with single wire unbalanced antennas, this new addition is small, compact and perfect for quick portable/emergency installations. Box cutter (for scraping enamel off of wire ends), (Helpful) Step drill bit for SO-239 connector, Paracord (for simulating and measuring lengths of windings on toroid), Antenna analyzer for HF frequencies (I use the RigExpert Zoom AA-55), Resistor(s) totaling about 3000 ohms (I used 1K and 2K ohm resistors in series). endobj 3 0 obj /Name /Im0 /Creator (XnView) << I only used two screws instead of four. Technical specification : Type : 49:1 Unun Frequency : 1.8 MHz - 7.3 MHz Turns ratio: 1:7 Impedance ratio: 1:49 Input Impedance: 50 Output Impedance: 2450 Power Handling (CW/SSB/ Digital Modes) : 2Kw of peak power / DM Modes 500 watts Core Type : 3 x FT240-43 by Fair-rite Co. Wire type: Enamel copper wire 2.0 mm (AWG 12) Assembled and tested. endobj 40-30-20-17. Wire lengths for the 4:1 ratio in models 4130, 4132, 4134, 4932 and 4935. 20/40/17m. In another life, I could have been a telephone engineer. 1863 1.49 swr 3915 2.50 7200 1.80 14.332 1.29 18.130 1.07 21.300 1.40 24.950 1.30 28.400 1.37 This is a great antenna that is . Cut the center conductor wire (free untwisted end of short wire) of the unun to the correct size, scrape the enamel insulation off of the free end with a box cutter, and solder it to the SO239 connector. This is not exactly a 1/2 wavelength in free space, but works for wire as it has a different velocity factor than "air". Lengths to avoid are not always the same as Ask Elmer Cannon". j#f5(fk0?P[polEo5b2-/oVZu1Qo-I6C/M@TbddPc#cdZZ|7+|o{}!F#?Go7ju|?wwgow/c2/W-m~~hn[S29OU}}r7lc]wsw[shS[#qbrrK[7*0,Xv{k+o {=*vo S__O~*=y/zk75O?yjCnXS{`~Ii'c_GxN. a more capable tuner - see AA5TB's We have also installed an additionalstud which can be used for a separate counterpoise wire rather than forcing the use of the feedline's coax shield. Winding 1:64 Matching Auto Transformer on the FT240-43 core. x {avla[g#+yt]Mk"B` xp[AO8;c=\b}|8p4cSmzgU7be,+i5ci6uq.x T/s@9uk-oZX;u`=U >8rsIXW B:uUVr6a] K1S Valentines Are (Almost) Out The Door! Cut the antenna radiator wire (free untwisted end of long wire) of the unun to the correct size, scrape the enamel insulation off of the free end with a box cutter, add a ring terminal, and secure to antenna radiator bolt with washers and lock washers. You also want the antenna to be at least 1/4 wavelength long for each band you plan to use. Longer wire is always more Windings are inserted into Teflon tubes increasingtotal breakdown to 10,000 volts. Custom mix low permeability ferrite by Fair Rite Products for maximum bandwidth. If you plan on stringing up a dipole you use 2 equal lengths of wire with the Balun in the middle. 2 0 obj <> "Can you please recommend schematics that are designed to tune setups like these? If you want all the bands from endobj These are sometimes known as a Magnetic Longwire Balun. 75/80 METER RESONATOR KIT FOR THE UJM-EFHW-40-10 200W 40-10m ANTENNA (QST, Oct 1926, "The Length of the 1 X FT240-43 Ferrite Toroid Core 43 Material(Mouser Electronics), 1 X SO-239 UHF PANEL JACK S/CUP SO-239(Mouser Electronics), No. The most common question I get asked is what is the correct length for my End Fed Long Wire Antenna? I used a homemade jig made of an SO239 chassis mount to bare wires, alligator clips, and a coax-jumper with PL259 (UHF male) ends; see picture below. You also So I just wanna say thank-you!! Use only the white gaps for your antenna lengths, and if Coverutilizes integralneoprene gasket for weatherproof integrity. The 49:1 End Fed Half Wave Antenna is very popular choice for home & field use, Ideal for limited space and stealth applications. Our Ask An Elmer panel discuss this question - what's the difference between matching units?Please consider using. x@ The short piece is for the primary winding of the transformer, and the long piece is for the secondary winding of the transformer. This is the latest and greatest transformer design for End Fed Half Wave (EFHW) antennas. We do not encourage any radio operations contrary to regulations. Links Save program output in file named 'f', and use If the choices are. << I have found this calculation to work well, however it depends on many factors such as wire used, location etc. I included the tools I used to analyze the transformer as well; this is only necessary if you are interested in analyzing your project. uR5ucE`_aksLjYT=hzRa]JucX7d}|'}`XRa>X << A 9:1 matches 50 ohms to 450 ohms and that turns out to be an ok compromise for feeding 50-100ft of wire for general purpose SW receive. When used with the stated lengths shown in thetable below, the 9:1 ratio will Based on the success of our model 4932, this 5kWconfigurationisalso perfect for matching both long and short length wire antennas for multiband use. wire to the UnUn "-" connector and then down to ground there it connects with the two other wires but neither the counterpoise nor the two other wires are connected to ground. Here are the final numbers (in my opinion) in green below that would be good for a long-wire antenna: (You may want to make a note of them), REVISED: 29 35.5 41 58 71 84 107 119 148 203 347 407 423, REVISION NOTE: We had a note from James, KB5YN, pointing out that one of my so-called GOOD numbers was 220 feet. Theme designed by Papathemes. Swr usually is all over the place and the tuner will just not do it's job. UJM-49-1 $56.99 Save up to 6% when you buy more. This article explains why the use of mix 43 for HF applications is almost always a mistake. %PDF-1.4 Shortwave Listening The counterpoise wire, This transformer is designed to be used with an end fed, Approx. There are numerous configurations available online that will accomplish this on multiple bands (Google search "end fed half wave antennas"). << HF Underground wiki Radio Hobbyist technical blogHFU Discord EuroPirate ChatPropagation DataTeamspeak Server, TDK CXA-2090 LCD Inverter Module New Old Stock USA Seller $19.99, Shortwave Pirate Radio In North America And Around The World, And Other Signals That Go Bump In The Night, Login with username, password and session length. 35-45, 54-64, 67-77. Picture Information. This was 9m vertically metres up a fishing pole and then about 5.8m out. endstream endobj Ham Satellites The magic lengths to use with the End Fed longwire is 29, 35.5, 41, 58, 71 and 84 feet I use a 29 foot wire with my PackTenna 9:1 balun for 40m-10m and then add a 28 foot length for better coverage on 80m when needed. In other Just a note, if you make one of these yourself, you need to twist together the first two wraps of the 14 winding wire with both wraps of the two winding wire. Picture 1 of 9. https://elginradio.wordpress.com/2017/10/17/end-fed-half-wave-antennas/. It is optimized for 3.5/7/10/14 MHz but will work reasonably well on all amateur bands from 80 meters thru 10 meters with a 135 foot length of wire and a short connection to ground. A standard recommendation (see QST, March 1936, p. 32, "An Unorthodox EFHW unun Resonant Long Wire 49:1 Transformer With BNC or SO-239 | Mobile Phones & Communication, Radio Communication Equipment, Antennas | eBay! endobj you're using different ham bands than in these examples, modify and rerun //-->, The "Best" Random Wire Antenna Lengths Two pieces of 14 gauge enameled wire (e.g., Thermalese), one short piece (about 1 foot in length) and one long piece (about 7 feet in length). Legal Stuff Tools 3 0 obj What these lengths are depend on your tuner and also the wire's surroundings and also the ground system. About Batteries results. 3. Re: 9:1 or 49:1 unun for end-fed long/random wire? understand its properties. document.getElementById("copyright_year").innerHTML = new Date().getFullYear(); Powered by BigCommerce. JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding. config file by typing gnuplot rw.gnu. Part List: "I received my third balun from Balun Designs this afternoon. /Length 6 0 R The idea Enclosure Height: 5.000 in. However, the list has been revised and is good for wires as long as 500 feet. Feeling a bit too lazy to calculate that by hand, however, I wrote a stream Again, the bands are USA, so change them 2 0 obj WwS`8o}=n,pjhzRa]Ju/Ru ni4=UvZ:u9*@ Xz+zZcXm}i[Z;Z>.u!*eQVjucXeqYZnSJu)U[n>>KXzZ.Lz sqxcGj]%q}i6=-?YTlnZXV6}=U >5`ZNxChzRa]JU.6TVr6a] Figure 2 Schematic of the 9:1 voltage unun . are easily converted to half wavelengths by the famous 468/f generally 4 0 obj The length should be calculated based on the lowest frequency to be worked. So a 49:1 impedance transformer is needed to match the 50 ohms of the coax at the feed line. 35. This homebrew 49:1 impedance transformer is the heart of any EFHW antenna you will build, most of the time. I actually did this first and before the connector was bolted to the box. One end goes straight into the While these lengths have been shown to work well on many bands, which While I have not done so yet, I plan on gluing the test cap to the back of the junction box. Start winding the toroid with the twisted wires at loop #1 (see schematic below). <>>> This design is excellent for matching both long and short length wire antennas for multiband use. this InJack's own words. Click to enlarge. Lengths of a half-wave or multiple must be avoided. 9:1 Unun 1.5-54MHz 2kW 9132S. Here I show finalizing the antenna, getting it in the air, and run. Use with other lengths can potentially damage the transformer depending on power level in use. var sc_security="1df091cc". Placing 3000 to 4000 ohms of resistance between the free end of the twisted portion of wires (the gound) and the free end of the long wire (the wire that connects with the antenna radiator after the 14th winding), can simulate adding an antenna radiator wire to the unun impedance transformer. Make sure the beginning few inches of twisted wire is not involved in the winding (i.e., just hanging down from the toroid). Generally an EFHW will be in the range of 2,000 to 5,000 ohms at the very end of the dipole when resonant. 0 Bullet 50:450 (9:1) HF Unun, 1.8-61 MHz, 1500 Watts, End Fed Antennas. is that for a given ham band there are min and max frequencies which /Kids [ 4 0 R ] AndWhat Is It Used For In Antennas? Built with the same craftsmanship as all our other For those that enjoy endfed antennas but want to run more power, Balun Designs now offers an excellent alternative. /BitsPerComponent 8 Jack, VE3EED, hopefully has solved a major headache we all have when we attempt to go thru the trial and error and frustration with getting the random wire to work where WE want it to work. used by hams for dipole lengths. It is not a good choice for working lower bands from a too short wire, that is, if you have cut your wire to a 20m halfwave, it ain't much punkin' for 40m, 80m, or 160m. Proudly powered by WordPress Jack, VE3EED, used center frequencies of thebands described in the article above, and I thought it would be nice to use band edges. Prescott Hamfest 2023 Saturday - May 13, 2023 - 0800 to 1200 MST Granville Elementary School 5250 Stover Drive, Prescott Valley, AZ 86314 The 2023 Prescott Hamfest is co-sponsored by the Yavapai Amateur Radio Club (YARC) and the Amateur Radio Council of Arizona (ARCA). This is a 4:1 Current Balun.That means it can match a 200ohm antenna to a 50 feed line. EFHW unun Resonant Long Wire 49:1 Transformer With 67' Antenna Wire. Let's have a look at a few details on how to build a 49:1 impedance . Computer Help Update guys:made the unun,the antenna was extended to about 37m length,and I added a counterpoise which is about 10m.The whole thing is much higher in the air,compared to where it was before. [ /PDF /Text /ImageI ] %%EOF SWR will vary based on topography, wire orientation and use of ground or counterpoise. A success! Privacy Policy Using a 49:1 transformer shoot for the best 50 match @ appx 2450 load over your working frequency bands. Just add or subtract as needed a little at a time toget the best compromise. Here is an ARRL Ultimately, this housing works fine, but it is heavy and clunky.). Ham Hints ", KiwiSDR Online Radio - 500 ft Northeast Beverage, KiwiSDR Online Radio - 400 ft South Beverage, KiwiSDR Online Radio - 10/11m dipole up 20 meters high. You'll want to have that wire up as high as you can get.. 49:1 or other high ratio transformers are for resonant "cut to frequency" antennas like the traditional zepp/fuchs antenna. Mike ab3ap, Editors note: Many thanks to Jack, VE3EDD (SK)and Mike, AB3APfor sharing their math and computerskills with us. An excellent way to attach a long wire antenna to the Ham It Up, this 1:9 balun has an SMA output port and high-quality spring-type terminal block input for your coax.

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