49:1 unun wire lengths 49:1 unun wire lengths

"Just received my new 64131 yesterday and was anxious to see how well it performed. (Note: I am not satisfied with this part of the project, so I will describe it here briefly. The WSPR map is so dense it looks like the US and Europe are just big blobs of color. a more capable tuner - see AA5TB's 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? endobj The length of a half wave antenna is calculated using the following formula: L (ft) = 468 / f (freq in mhz). A few more comments about this 49:1 autotransformer EFHW design. 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. is that for a given ham band there are min and max frequencies which ", KiwiSDR Online Radio - 500 ft Northeast Beverage, KiwiSDR Online Radio - 400 ft South Beverage, KiwiSDR Online Radio - 10/11m dipole up 20 meters high. For example, when adding a 1/4w tiger tail to a 2m ht with a halfwave for antenna will likely show no improvement at all in tx or rx strengths. I plotted the results for the U.S. CW band edges for use with my4 band Elecraft K1 qrp rig. /Contents 5 0 R 748 0 0 752 0 0 cm Anyway, an old friend mentioned 'MyAntenna.com' but they were closed for the summer. Here's a list of recommended lengths of wire to use with a 9:1 unun. Meet 'Balun One Nine', a small, cost-effective balun. /ProcSet 7 0 R >> 9:1 Unun 1.5-54MHz 2kW 9132S. Change the program to use 423 if desired.) The matching unit The impedance at the end of a half wave antenna is somewhere between 2000-5000 Ohms. google_ad_width = 160; The "Super Bullet" End Fed Long Wire Antenna Matcher - 1500/3000 watt rated for Super-Punch of your signal! I'm consistently pleased with the quality and ease of use of Balun Designs products and look forward to my next purchase in the future. /* Ad banner 160 x 600 */ 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 . endobj Ultimately, this housing works fine, but it is heavy and clunky.). 9 0 obj Recommended wire lengths for Unun models 9130, 9132 & 9135 Table shows typical SWR relative to installed wire length. In the first year using this unun with a random length endfed wire (Aluminum Elec fence wire at that) I managed to confirm WAS via LoTW on 10m, 15, 17, 20, 30, 40, 80. . Power handling is 100 watts CW / SSB & 25W Data modes. Clansman End Fed Long Wire Antenna Used. The Short Answer Would Be That an UnUn Is a "UN balanced to UN balanced" matching transformer. 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. random wire page. frequencies for your country or favorite modes. 2 0 obj So for example 80m could range in length from 120 to 133 feet. 6 0 obj You have to give up a band or two, like 60m and 6m, as 49:1 UNUN IMPEDANCE XFORMER FOR END FED HALF WAVE ANTENNA. 73. JACK, VE3EED Attaching a counterpoise wire to the common point of the auto-transformer provides the antenna radiator something to push against rather than the coax shield. I have not done this yet. Tools This design is excellent for matching both long and short length wire antennas for multiband use. In other Free Postage. program or two to do all the dirty work. 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. Shortwave Listening VSWR analysis of the antenna in the field showed that VSWRs between 3-5.5 from 40M to 10M. The length should be calculated based on the lowest frequency to be worked. There are numerous configurations available online that will accomplish this on multiple bands (Google search "end fed half wave antennas"). 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. Power Handling (CW/SSB): 100 W/200 W Enclosure Width: 2.500 in. 4 0 obj 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. the C code, in Matlab or Octave get a plot by simply putting the UJM-49-1 $56.99 Save up to 6% when you buy more. The length of enamelled copper wire per winding for the T-200-2 powdered iron toroid core is determined by length per winding = 50mm per turn plus 250mm tails. Usually any wire length that is non resonant, like those shown above, will work with the 4:1 ratio. recommended on VE3EED's page because I use all halfwave 73, 1 0 obj /Filter [ /FlateDecode ] 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. 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. All you need for a random wire antenna is some wire, your tuner, one or more supports up as high as you can get them to string the wire from the supports to the tuner, at least one or two insulatorsand a little time. STORE After winding #2 is made and extends down the backside of the toroid, untwist the wires. 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. Well, I didn't think it would make any difference at that many multiples. <> x 4 in. 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. 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). SO-239 connectors are silver plated with Teflon insulation. Generally an EFHW will be in the range of 2,000 to 5,000 ohms at the very end of the dipole when resonant. Superglue 2 toroids together. SWR will vary based on topography, wire orientation and use of ground or counterpoise. Contact Code Practice The length should be calculated based on the lowest frequency to be worked. stream /Type /XObject Usually any wire length that is non resonant on the band or bands desired will work with the 4:1 ratio. 40-30-20-17. /CreationDate (D:20221212112042) stream endobj An end fed half wave antenna is one of a specific length depending on the frequency that it is to be used on, for example, an end fed half wave antenna for 80 meters is about 130 long. I'll get a 9:1 unun,and use a suggested random wire length to avoid half-wave and it's multiples then,that sounds like the best things I can get out of this setup. Each vertical blue line represents an amateur radio band. First, it is important to understand the difference between the end fed half wave and a random wire (or "long wire") antenna: the random wire is just a piece of wire that is matched to 50 Ohm impedance using an antenna coupler, sometimes adding a 9:1 unun. IMG_2.jpg Step 2: Take the 6 feet of 18 gauge enameled copper wire, measure 11" from one end and fold it back. stream 9:1 Unun EF Random Long wire matching Transformer with BNC or SO-239. Re: 9:1 or 49:1 unun for end-fed long/random wire? My commercial EFHW is 130 feet long for 80 and up, and my 40 meter homebrew antenna is about . We do not encourage any radio operations contrary to regulations. Privacy Policy I actually did this first and before the connector was bolted to the box. 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. . 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. Moving the pot up and down gives a feel for the SWR versus antenna impedance sensitivity. endstream "I received my third balun from Balun Designs this afternoon. 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. Cannon". plan to use. Click to enlarge. /Type /Page google_ad_height = 600; An Unun is used to match an unbalanced line to another unbalanced line. I made just a touch over 100 QSOs today with the new unit. They just saved you and I loads of time and frustration. endobj 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. Let's have a look at a few details on how to build a 49:1 impedance . , Reprinted with permission of Hamuniverse, this is an excellent explanation of SWR and how to best me 22.00 + 5.00 Postage. thank you. Jack, VE3EED - SK. this endstream endobj startxref 35. Then verify it with your installed antenna and SWR measurements. 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. A Balun is used to match a balanced line to an unbalanced line. 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. Proudly powered by WordPress Computer Help these are the worst lengths and you want to be as far from colored often can't match it. You can take one of these 49:1 transformers and use the 468/freq (Mhz) formula to calculate the length you need in feet. Lengths of a half-wave or multiple must be avoided. Ham Radio News! My homemade 49:1 EFWH with a 60 wire (cut for 40M) would do just fine! 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.). 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. Connect this ring terminal to one of the SO239 chassis bolts. . Custom mix low permeability ferrite by Fair Rite Products for maximum bandwidth. Winding 1:64 Matching Auto Transformer on the FT240-43 core. are easily converted to half wavelengths by the famous 468/f generally 7 0 obj >> This is not exactly a 1/2 wavelength in free space, but works for wire as it has a different velocity factor than "air". Yes, with the recent surge in popularity of the end-fed half-wave antenna, the 49:1 balun has also become the defacto ratio for use with them. Site Map 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. Repeater Basics Work all bands from 80 through 10 on it. For a better experience, please enable JavaScript in your browser before proceeding. 0 Feeling a bit too lazy to calculate that by hand, however, I wrote a Electronics I imported my spools from the US, but I have seen them on Ebay in the UK. The second smallest number I measured was 2.7pF, derived from the self resonance at 2.72 MHz with the magnetizing inductance (measured at 25.8 H) with the secondary open and the output wire folded to a small 1/2 length. The graph below shows lengths to avoid for different collections of bands. Care to buy us a beer? Let the now free end of the short wire hang down from the toroid. 40-10m with a 49:1 Unun. | https://elginradio.wordpress.com/2017/10/17/end-fed-half-wave-antennas/. A VSWR sweep of the unun after adding a 100pF capacitor shows an SWR <5:1 from 160M to 10M. Palomar Engineers employs a dual core matching system that offers wide bandwidth (1-61 MHz), 500 watt PEP rating, and a connection for a counterpoise or ground if desired. I'm looking forward to getting off work and hitting 40 & 20 meters again!! 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. 27.00 (27.00/Unit) Free Postage. 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. 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). Swr usually is all over the place and the tuner will just not do it's job. /XObject << /Im0 9 0 R >> 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. This is a 4:1 Current Balun.That means it can match a 200ohm antenna to a 50 feed line. The fewer bands, the fewer high impedance regions to avoid. For instance, to work 40m be sure the antenna is at least 8 0 obj >> endobj A png image named g.png will be created. <>>> $119.95. high the other 1.5m (4.5feet). For those that enjoy the LNR and Hy Endfed antennas, but want to run more power, Balun Designs now offers an excellent alternative. That meant calculating all the way to 32 multiples of a half wave on 10 meters. (A t0 B) Fold over 6 to 8 inches and twist it together. CQ-Calling All Hams! 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. That type of wire antenna could be lower than 50 ohms at some frequencies and over 2,000 ohms at . I use this 8010 EFHW at home, too. 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. 49:1 or other high ratio transformers are for resonant "cut to frequency" antennas like the traditional zepp/fuchs antenna. % If you want all the bands from %PDF-1.5 % So for example 80m could range in length from 120 to 133 feet. Antenna Safety! The key is you want to stay at least 1/2w long but not near 3/4w for any band of interest. Because I'm more visually oriented I then plotted the many overlapping "red zones" and ended up with the page at: In stock . ?7{*. 31 A 9:1 unun is a transformer that reduces the impedance at the input by a factor of 9. A 49:1 would match 50 ohms to about 2,450 ohms and a 64:1 matches to 3,200 ohms, typical of a 1/2 wave end fed. The random wire antenna is probably one of the least expensive, easiest and cheapest HF antennas to use if you have a tuner and you want to get the "most" out of a length of "random" wire without having to pull out that calculator, doing the math, getting the center insulator built orbought, running the feedline, and all the rest that goes with putting up a more elaborate antenna. K1S Valentines Are (Almost) Out The Door! PVC Junction Box(Home Depot), 1 x 1/2 in. At multiples of half wavelengths of the 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. The graph below shows lengths to avoid for different collections of bands. understand its properties. 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 . This homebrew 49:1 impedance transformer is the heart of any EFHW antenna you will build, most of the time. End fed 49:1 60ft wire (using coax as the counter poise. /Name /Im0 35-43, 49-63, 70-85. Drill a hole in one side for the antenna radiator wire mount (for a #8 bolt in my build). Allows the internal tuner of most rigs to tune remotely mounted single wire antennas. var sc_invisible=1; You need to use these lengths and the longer ones . That is the 10th multiple of a half wave on 15 meters. END FED "RANDOM WIRE" HF DIPOLE 9:1 ANTENNA RELACEMENT ELEMENT ONLY $28.99 Save up to 6% when you buy more. Here Is a 250 Watt Home-Brew That I Made In about an Hour. << An UNUN is needed to match the high impedance of an end fed antenna (2k-4k ohms range). I will also find some sort of heat resistant packing material to help hold the transformer in place. For example, 40-30-20-15m bands for my 4 band Elecraft K1 qrp rig. . Be sure to review the various lengths in the link below to obtain the lowest SWR across most if not all HF bands. This transformer converts the impedance at the end . Enclosure Height: 5.000 in. Multiples are on C and Ham Radio Videos! JavaScript is disabled. X:nzf4p:t;r }~_HOZcX:^$* J^XZuu|"nX/Wkw0hA>y1(z2+v_Xzu[/:^$*m*>hk_:+c{ endobj Downward impedance transformation by factor of 49. End Fed Half Wave Antenna Coupler Schematic - 7-30MHz. it is easy to pack and easy to install. I used the RigExpert Zoom AA-55 to test VSWR of the 49:1 unun impedance transformer. So for 80 meters (say 3.525 MHz) this gives you about 133' of wire. 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. The WorldwideDX Radio Forum was originally established in 2001. 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. Start winding the toroid with the twisted wires at loop #1 (see schematic below). Lowest Band of Operation: 160 meters Highest Band of Operation: 10 meters Additional Information LDG Electronics RU-9:1 Unun For best results, use the Wire Length Feet 1.8 MHz 3.7 MHz 5.3 MHz 7.1 MHz 10.1 MHz 14.2 MHz 18.1 MHz 21.2 MHz 24.9 MHz 28.5 MHz 50.1 MHz While I have not done so yet, I plan on gluing the test cap to the back of the junction box. Start winding the Matching Auto Transformer, each pass through the center of the core equals one turn. So I just wanna say thank-you!! Drill another hole in the same side as the antenna radiator wire mount hole. Some important and helpful references I used for this work: https://elginradio.wordpress.com/2017/10/17/end-fed-half-wave-antennas/. gnuplot q answers on D - one setting. /Length 6 0 R Tweak the antenna length if necessary and then maybe adjust the turns ratio again. Here they are in order: Best SWR was . For those that enjoy the LNR and Hy Endfed antennas, but want to run more power, 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, ttaching a counterpoise wire to the common point of the auto-transformer, provides the antenna radiator something to push against rather than the coax shield. We hoisted the free end of the antenna wire approximately 30 feet into a tree. Theme designed by Papathemes. /Pages 3 0 R Just add or subtract as needed a little at a time toget the best compromise. tuner the colored bands below are the best lengths as long as your Wire-Lengths-for-9-1-ununs.pdf Created Date: 12/12/2022 11:20:42 AM . 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. As typically A good place to start is the formula 468 / f (MHz) for a 1/2 wavelength wire antenna. Hope it's clear now, if not. Upon further research, I remade it tightly twisting those two separate wires together, just as it shows in archjeb's picture, and it worked surprisingly well. So a 49:1 impedance transformer is needed to match the 50 ohms of the coax at the feed line. 49:1 End Fed Half Wave Antenna 40-10M 100W Version Bands of operation 40,20,15 & 10m using 67 feet of our UV, Ozone resistant Antenna wire. Superior Essex Heavy build polyamideimide. 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