49:1 unun wire lengths

Beginning from the 3rd band from the left, the vertical blue lines are: 160M, 80M, 60M, 40M, 30M, 20M, 17M, 15M, 12M, (11M), and 10M bands. 2 0 obj Continue on winding the long wire through the toroid to complete loops 3 through 14 as shown in the schematic below. Playing with end-fed wire antennas and 9:1 ununs So for example 80m could range in length from 120 to 133 feet. used by hams for dipole lengths. Here they are in order: /Producer (XnView, http://www.xnview.com) 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. endobj If you would like to use high power up to legal limit with a single end fed wire antenna (not necessarily a half wave) consider using our Model 9135 along with one of the wire lengths shown in the Installation Notes. =======================, 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: a more capable tuner - see AA5TB's When do you use a 1:1, 9:1 or a 49:1 balun? << End-Fed Half-Wave Antenna Kit - American Radio Relay League The vertical (y-) axis shows the VSWR and the horizontal (x-) axis shows the frequencies. Caution: When used atfull power rating of 1kW, the antenna must have a low SWRon the band selected and be used on a 50% duty cycle. There are numerous configurations available online that will accomplish this on multiple bands (Google search "end fed half wave antennas"). The idea N4UJW. This transformer is designed to be used with an end fed half wavelength of wire only. bands as possible. the C code, in Matlab or Octave get a plot by simply putting the Here is an ARRL The 49:1 impedance transformer will help you bring down the high impedance of your resonant EFHW antenna to almost 50 Ohm. The "9:1 UNUN" are for random length wire antennas fed at the end. . PDF Construction Details 49:1 Un-Un For End-Fed Resonant HalfWave Antenna We are working every day to make sure our community is the best Radio Hobbyist's site. The 30 day return period lapsed before I could get the antenna deployed to test it. https://www.kb6nu.com/playing-end-fed-wire-antennas-91-ununs/, http://www.hamuniverse.com/randomwireantennalengths.html, https://www.youtube.com/watch?v=sty7RlXQoJI, https://www.youtube.com/watch?v=WwJnXTVUrgI, Quote from: refmo on October 15, 2019, 2036 UTC, Quote from: joczo on October 16, 2019, 0815 UTC, http://www.w3pga.org/Antenna%20Books/Reflections%20III.pdf, http://www.arrl.org/files/file/Technology/tis/info/pdf/7007024.pdf, http://www.tasrt.ca/AntennaTips/AntennaTips.htm, http://www.wb2rcb.com/documents/balunlin.pdf. This type of antenna is very easy to install because there is no need . A Balun is used to match a balanced line to an unbalanced line. I included the tools I used to analyze the transformer as well; this is only necessary if you are interested in analyzing your project. EFHW unun Resonant Long Wire 49:1 Transformer With BNC or SO-239 A 50 foot run of RG-8X coax connected the antenna into the LDG Z100-plus tuner and then a Yaesu FT-891A transceiver. x 2 in. One single wire, no solder connections,very simple.all the way from the tuner to the end support. SO-239 (UHF female) chassis mount with screws, nuts, lock washers. 9:1 or 49:1 unun for end-fed long/random wire? That's it in a nutshell..or is it? Use only the white gaps for your antenna lengths, and if endobj rig, often with no feedline, and the other end in the air attached to One is for the top of the box so that it can be hung up. Re: 49:1 transformer for EFHW antenna - groups.io IMG_2.jpg Step 2: Take the 6 feet of 18 gauge enameled copper wire, measure 11" from one end and fold it back. Drill a hole in one side for the antenna radiator wire mount (for a #8 bolt in my build). endstream Theme: Newsup by Themeansar. Experimenting with 1:64 and 1:49 end-fed antenna Ununs on - reddit X:nzf4p:t;r }~_HOZcX:^$* J^XZuu|"nX/Wkw0hA>y1(z2+v_Xzu[/:^$*m*>hk_:+c{ It is important to use a counterpoise. Tweak the antenna length if necessary and then maybe adjust the turns ratio again. endobj The most common question I get asked is what is the correct length for my End Fed Long Wire Antenna? It uses an FT140-43 or FT240-43 toroid in a 49:1 impedance matching unit at the base and a 110 micro Henry (H) coil to act as a loading coil for 80m and a choke to stop higher frequencies using the last 2m of wire. Repeater Basics 9:1 Unun 1.5-54MHz 2kW 9132S. , Reprinted with permission of Hamuniverse, this is an excellent explanation of SWR and how to best me 1:1, 9:1, 49:1 Matching Units - What's the difference? - YouTube Thanks for your answer,I will probably go with the 9:1 then. Q However, the radio didn't tune up very well on 15 meters. 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. "Can you please recommend schematics that are designed to tune setups like these? The goal of the impedance transformer is match the 50 ohm impedance of the feedline (coaxial cable) with the potential 3000 to 4000 ohm impedance expected from an end-fed half wave antenna wire radiator. /ProcSet 7 0 R >> EFHW unun Resonant Long Wire 49:1 Transformer With BNC or SO-239 PDF Wire-Lengths-for-9-1-ununs - OM0ET The novel thing was that I only built it the day before and it uses a Coghlan camping washing line spool with the string taken off and about 21m of wire wound onto it. 35. At multiples of half wavelengths of the So for 80 meters (say 3.525 MHz) this gives you about 133' of wire. . 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.). I connected it to a 33 wire running from my balcony, through the trees, and ran WSPR overnight to check things out. , This is a partial reprint (with permission) of an excellent series of articles published by KV5R SSTV endobj You also want the antenna to be at least 1/4 wavelength long for each band you plan to use. License Study 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. Technical specification : Type : 49:1 Unun Frequency : 1.81 MHz - 30MHz Impedance ratio: 1:49 Input Impedance: 50 Output Impedance: 2500 Power Handling (CW/SSB) : 250W Core Type : 1x FT240-43 by Fair-rite Co. Capacitor 100pF 3KV Assembled and tested. When you're 1/2w long you're around 2k ohms or more where the balun won't under or over xform; as you approach 3/4w your z is going to drop to where a coax match can be made just by soldering the wire to the center conductor sans balun - more or less the principle of the windom and ocf dipole. <>>> 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). <> endobj SEARCH 9:1 UNUN - MyAntennas.com 9:1 Magnetic Longwire Balun / Unun - M0UKD - Amateur Radio Blog The transformer usually used with an end fed wire is a 9:1 transformer. 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] ?7{*. 1:64 vs 1:49 balun for an end fed?? : r/amateurradio - reddit Drill another hole in the same side as the antenna radiator wire mount hole. for your country and favorite modes of operation. A few more comments about this 49:1 autotransformer EFHW design. This design is excellent for matching both long and short length wire antennas for multiband use. %PDF-1.7 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 . Usually any wire length that is non resonant on the band or bands desired will work with the 4:1 ratio. PVC Junction Box(Home Depot), 1 x 1/2 in. For a better experience, please enable JavaScript in your browser before proceeding. Notice from column f that there is no length giving low impendance for it is easy to pack and easy to install. << 4 0 obj ), Note that Jack, VE3EED,went SK several years agohe will be missed. /Filter [ /FlateDecode ] endobj Advertising Info End-fed wire antenna lengths - Amateur Radio Stack Exchange EFHW unun Resonant Long Wire 49:1 Transformer With 67' Antenna Wire. q Any SWR measurement taken with the transformer at the feedpoint should not exceed 1.5:1withNOtuner in use. Thus a 1/4 wave for 20m@16ft, 40m@33ft as examples are not going to work. We do not encourage any radio operations contrary to regulations. Thank you so much for such a great product! Scott builds a compact random wire antenna with 9:1 Unun is that for a given ham band there are min and max frequencies which So, having nothing better to do one day, I re-did the calculations going out to 500 feet. Use with other lengths can potentially damage the transformer depending on power level in use. <>/Metadata 239 0 R/ViewerPreferences 240 0 R>> Jack, VE3EED, used center frequencies of thebands described in the article above, and I thought it would be nice to use band edges. The following is a list of materials required to make a 49:1 unun impedance transformer for an end-fed half wave antenna. My commercial EFHW is 130 feet long for 80 and up, and my 40 meter homebrew antenna is about . %PDF-1.5 % V#X~[Z?\ZcX:-Y?&Y?IqTnayZ{jTZOub}=UTWu1G>o.,RaT c=W>:sECXTkc=X I got three FT240-43 toroids (two would be lighter, but three increases the curie point so it can handle longer duty cycles), a spool of the 14 gauge enameled wire . The "Almost Random" Wire Antenna - KB6NU's Ham Radio Blog This antenna, which works on 10, 15, 20, and 40 meters, has a very high impedance of around 2,500 Ohms. 80m up, W3EDP's 84' antenna, 17' counterpoise is probably the way to go. The 49:1 unun with 3000 ohms of resistance shows a VSWR under 10:1 from 160M to 15M, and less than 3:1 from 80M to 20M. Legal Stuff Product Reviews so that it is not a halfwave multiple of any frequency you want to use. Links Enclosure Height: 5.000 in. 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. 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 So a 49:1 impedance transformer is needed to match the 50 ohms of the coax at the feed line. HF & Shortwave 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. For example, This is a 4:1 Current Balun.That means it can match a 200ohm antenna to a 50 feed line. I will also find some sort of heat resistant packing material to help hold the transformer in place. An UNUN is needed to match the high impedance of an end fed antenna (2k-4k ohms range). A small ring terminal for 14ga wire that fits these screws would be helpful too. You also uR5I5z G^u2`j[}+sy9 Note: My (A to B) length was 6 inches. To DB's point of a single band antenna, this 49:1 transformer is a good choice for a single band matcher. 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. This homebrew 49:1 impedance transformer is the heart of any EFHW antenna you will build, most of the time. 6 0 obj >> x 4 in. Random wire lengths you should and should not use! installed, it is a compromise antenna but great for portable use because Stacked coreswithwinding configured as 49:1auto transformer. If you want all the bands from hbbd```b``^ "Cs;D2 I*`0D;+EVUHy`qml0{YVw`b0i DvkAh |"w I2% ?W%@Fg`` 6 I wrote a small C program that does just what Jack did, butI used the band edges. Please note that I will not be describing the construction of the antenna wire radiator here. high the other 1.5m (4.5feet). A way of connecting the analyzer to the transformer. >> /Type /Pages >> Site Map A 9:1 unun is a transformer that reduces the impedance at the input by a factor of 9. End Fed Half Wave Wire Antennas | N6CC Hopefully these random wire length calculations will help us all make this "easy" antenna work better! PDF portable multi-band End-Fed Half Wave (EFHW) antenna for 40-10m often can't match it. Use a slide rule! I used the RigExpert Zoom AA-55 to test VSWR of the 49:1 unun impedance transformer. How to Make a Balun or Unun : 3 Steps - Instructables 0$Ve Vacation Closure - See Homepage for Next Availability. 1. Proudly powered by WordPress x@ The following wire connections do not need to be made in the order I described. endobj It will be good for 15m, and 10m. A png image named g.png will be created. Figure 3 Wiring of the 9:1 voltage unun. 4 0 obj /Resources << 49:1 UNUN Transformer 2 Kw 160 - 40 m - Wire Antennas https://elginradio.wordpress.com/2017/10/17/end-fed-half-wave-antennas/. Ham Radio Videos! In theory, my LDG Z100 Plus autotuner should be capable of matching the impedance of this 49:1 transformer with a end-fed half wave length antenna radiator across all amateur HF bands. good show chuck, you said ya picked up a 430, did i tell i fried the 0ne i got from you, can anyone point me in the direction of a 2 pill schem for the HG 2879? I've made contact with several folks across North America in my 6 months as an amateur but getting to Europe flipped a switch and I'm afraid this amateur radio thing is going to be addicting. I attached the toroids to a PVC DWV test cap with 3 cable ties. "Here's the word on random-wire antennae.". /Type /Page The counterpoise wire does not have to be similar in length to the main radiator wire and just a short wire is all that is needed, about 0.05 . <> (wlSR9dJ_x%+VHX4FRr 3>;g^x%g'wkJu,i~#Q"2|WGf[!_m]#&1$)R.{--" 'dGO;=_B$T}". and experiment. The major point of this message is to tell you that approximately 20 minutes after I connected the balun unit to the antenna, I made contact with a gentleman in Italy-my first European contact!! A VSWR sweep of the unun after adding a 100pF capacitor shows an SWR <5:1 from 160M to 10M. https://elginradio.wordpress.com/2017/10/17/end-fed-half-wave-antennas/. 40-30-20-15m bands for my 4 band Elecraft K1 qrp rig. So is an essential piece of gear to have. End Fed Antennas. 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 . Midi Music Meet 'Balun One Nine', a small, cost-effective balun. This is considered a random wire end fed antenna, not to be confused with a half wave end fed antenna which uses a 49:1 or 64:1 unun and a wire that is a half wave length. To summarise the results WRT to reference antenna consisting of 30ft wire vertical fed with auto- Drill a hole in the top for an eyehook (to be used to secure the unun to whatever it is you want to hang it from.). | We pride ourselves on welcoming Radio Hobby enthusiasts of all types, while offering unbiased, informative, and friendly discussion among the members. I usually go with a 3.2k transformation wire winding ratio of 8:1 which is a final impedance conversion of 64:1 (50ohm * 64 = 3.2k ohm). 9:1 or 49:1 unun for end-fed long/random wire? You'll want to have that wire up as high as you can get.. You need to use these lengths and the longer ones . 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. %PDF-1.5 June 8, 2022 at 9:17 am. /Creator (XnView) For those that enjoy the LNR and Hy Endfed antennas, but want to run more power, Balun Designs now offers an excellent alternative. Each vertical blue line represents an amateur radio band. So, if you connect a length of wire that presents an impedance of about 450 to the input, you'll get an impedance of about 50 on the output. /* Ad banner 160 x 600 */ Random Wire Antennas - Best Lengths To Use For Random Wire Ham Radio End Fed Antenna with a 1:64 Matching Network The graph below shows lengths to avoid for different collections of bands. /Width 748 They just saved you and I loads of time and frustration. Weight: 0.380 lbs. Here's a list of recommended lengths of wire to use with a 9:1 unun. Tune Around! While I have not done so yet, I plan on gluing the test cap to the back of the junction box. (QST, Oct 1926, "The Length of the all US ham bands. Even easier than Turns 1 through 14 are secondary windings (the long wire). A so-called random wire antenna is an end fed antenna. A couple hours later when I sat down to do some more DXing, I made contact with a gentleman in Slovenia-my second European contact. That meant calculating all the way to 32 multiples of a half wave on 10 meters. Reading Room In fact, the 9:1 unun that I built is actually an autotransformer. For instance, to work 40m be sure the antenna is at least Part List: you're using different ham bands than in these examples, modify and rerun That type of wire antenna could be lower than 50 ohms at some frequencies and over 2,000 ohms at . stream Hope it's clear now, if not. 2 0 obj In another life, I could have been a telephone engineer. and leave the unun on the ground. Our Ask An Elmer panel discuss this question - what's the difference between matching units?Please consider using. A good place to start is the formula 468 / f (MHz) for a 1/2 wavelength wire antenna. Liquidtight NM 90-Degree Connector(Home Depot). 1 0 obj 1 0 obj This is a followup video to #344 where I assembled the 49:1 UNUN kit from HF-Kits / ARRL. The 49:1 End Fed Half Wave Antenna is very popular choice for home & field use, Ideal for limited space and stealth applications. The bandwidth where SWR was below 2:1 was about one MHz. I did not want to put the transformer in the housing until I tested it. 73. JACK, VE3EED /Length 10 0 R 3 0 obj Start winding the toroid with the twisted wires at loop #1 (see schematic below). u?X`f0&/Ri;W0Tn_*TX:ug This article details the construction of the transformer. //-->, The "Best" Random Wire Antenna Lengths The key to end fed antenna success is the matching network interface between the long wire antenna and the coax feed line and feed line choke at the transceiver. 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. These dimensions were derived from modelling the antenna in EZNEC. 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. $1YacO5Q}YC\>qZ } The unun was floating at about 15 feet above ground. Random Wire Antenna Lengths - University of Delaware 73, Simple End Fed Half Wave for 40m (and how it works) JC[ d8O[UKKQ{yZ{G 'Upno_*~8uo a@G`' zxUHXW&`}mEp`?i0 oE:N0-/t"t.-? I have never tried to transmit through it, but it proved the optimal ratio for receiving with my setup. [ /PDF /Text /ImageI ] So you have the freq range of interest and the total length of the wire, figuring out wich balun will be a better match for 50ohm coax should be easy. 9:1 UnUn End Fed Long Wire Lengths - Pretty Simple. At this point, Ive only used the 49:1 tap, but plan to take the 64131 whenever I operate portable. 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). The table below represents half wave lengths and multiples that you DO NOT WANT TO USE! He knew that in order for the tuner to "see" a fairly low swr to work within it's range,that the antenna had to be NOT A HALF WAVE ON ANY FREQUENCY that we wanted to us, because a half wave will give us a very high impedance and the resultingswr into a 50 ohm transmitter! The key is you want to stay at least 1/2w long but not near 3/4w for any band of interest. Model 49131 - 49:1 - 80-10m EFHW - Up to 1kW - Balun Designs Odds are that most lengths are fine though, so the easiest solution is to pick a length based on something else (like, the room you have available) and if you get unlucky, roll the dice again. are easily converted to half wavelengths by the famous 468/f generally thank you. Power handling is 100 watts CW / SSB & 25W Data modes. We hoisted the free end of the antenna wire approximately 30 feet into a tree. The counterpoise wire, This transformer is designed to be used with an end fed, Approx. (A t0 B) Fold over 6 to 8 inches and twist it together. http://udel.edu/~mm/ham/randomWire/. Clansman End Fed Long Wire Antenna Used. Make sure the beginning few inches of twisted wire is not involved in the winding (i.e., just hanging down from the toroid). random wire page. In addition to multiples, EFHW Antenna and 49:1 UnUn | WorldwideDX Radio Forum Save program output in file named 'f', and use CQ-Calling All Hams! VSWR analysis of the antenna in the field showed that VSWRs between 3-5.5 from 40M to 10M. Be sure to review the various lengths in the link below to obtain the lowest SWR across most if not all HF bands. 2. Recommended wire lengths for Unun Balun - Webclass.org This will be for an eyehook in order to provide strain relief for the radiator wire. 49:1 vs. 9:1 Transformer for RX only? - RadioReference.com Forums A level of 500-600 watts is the maximum with a further reduction onany band measuringabove 3:1. stream endobj Best SWR was . The Short Answer Would Be That an UnUn Is a "UN balanced to UN balanced" matching transformer. This Balun Designs unit is replacing an MFj 1982 HP EFHW balun that was DOA when it arrived last May. Mike ab3ap, Editors note: Many thanks to Jack, VE3EDD (SK)and Mike, AB3APfor sharing their math and computerskills with us. 49:1 or other high ratio transformers are for resonant "cut to frequency" antennas like the traditional zepp/fuchs antenna. program or two to do all the dirty work. . I have not done this yet. recommended on VE3EED's page because I use all halfwave google_ad_height = 600; In other "Just received my new 64131 yesterday and was anxious to see how well it performed. 748 0 0 752 0 0 cm Recommended wire lengths for Unun models 9130, 9132 & 9135 Table shows typical SWR relative to installed wire length. A success! Ham Satellites gnuplot /Kids [ 4 0 R ] 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. Code Practice Superglue 2 toroids together. Its really an impedance transformer (9:1) to feed a high impedance, end fed (unbalanced) random wire which is likely to be a few hundred ohms, and transform it into something closer to a 50 (unbalanced) coaxial input, hence UnUn. NEMA rated 4x marine grade junction box for outdoor installations. Lengths of a half-wave or multiple must be avoided. (Also note that here may be instances where the suggested lengths may not work exactly due tothe many variablesin the surroundings of the antenna, wire length variances,your tuner, it's height above ground, it's construction,etc. but instead of the Jaycar core, we used an Amidon FT-240-43; anyhow, we also followed the UnUn with a 1:1 guanella choke and boxed everything, at that point, we . FCC Information endobj Support The Site unavailable, a random wire can save the day, but it is important to I'm not saying aliens are in the radio, but aliens definitely are in the radio. /Count 1 He was so impressed that he purchased a 9:1 unit from you, his will be delivered Saturday. << Performance is ASTOUNDING, far exceeding my expectations. << 3. Solder a the 100pF capacitor between the center conductor wire and ground wires. stream As typically Re: 9:1 or 49:1 unun for end-fed long/random wire? x[q;`&z`uAlo#V@;hvOYt, @*Ys~_W_~W_aw_ p[N+}[t-^oLy}xz>7/~c|ZZt75;kN^=>Y+_~|b~"m*tw>xG=x6Qwz|xvz- When used with the stated Balun Designsis now offering a low power alternative for those who want to use an End Fed Half Wave for portable or temporary installations. 1 0 obj Here Is a 250 Watt Home-Brew That I Made In about an Hour. this Contact 9:1 Unun 1.5-54MHz 2kW 9132S - The DX Shop Limited Par EF 20 and par EF 40 (I realize for 17m I would prob just add that band to a 49:1 balun) That's that my question is. . I swept the VSWR of the unun and resistors as described from <1 to 55MHz. BUILD INSTRUCTIONS FOR 49:1 UNUN IMPEDEDENCE TRANSFORMER: WX1MAR and I brought the DIY 49:1 unun with a borrowed antenna radiator wire cut for 20M half-wavelength to Ashland State Park K-2417 in Massachusetts for a Parks-on-the-Air (POTA) activation.