49:1 unun wire lengths

Post Reviews EFHW Antenna and 49:1 UnUn | WorldwideDX Radio Forum Please note that I will not be describing the construction of the antenna wire radiator here. << . Care to buy us a beer? excellent page for EFHW info - or, addressed below, to cut the wire Picture Information. Reading Room 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. /Title (Wire-Lengths-for-9-1-ununs.pdf) /ModDate (D:20221212112042) 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. 6 Screws/ Nuts/ Washers/Wing Nuts And Ring Connectors, 1 X Mica Capacitors 100pF 500V 5%(Mouser Electronics), 1 x 4 in. The 30 day return period lapsed before I could get the antenna deployed to test it. RFI Tips and Tricks Connect this ring terminal to one of the SO239 chassis bolts. endobj 2 eyehooks with washers and nuts (I used #8 diameter, but size is up to you.) Make sure the beginning few inches of twisted wire is not involved in the winding (i.e., just hanging down from the toroid). Use with other lengths can potentially damage the transformer depending on power level in use. N4UJW. shown in the column e. var sc_project=8077274; results. Again, the bands are USA, so change them That type of wire antenna could be lower than 50 ohms at some frequencies and over 2,000 ohms at . 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 . 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. 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. 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. I plotted the results for the U.S. CW band edges for use with my4 band Elecraft K1 qrp rig. are blocked out because an antenna should be at least that long. 9:1 UnUn End Fed Long Wire Lengths - Pretty Simple | ve3ips I'm not saying aliens are in the radio, but aliens definitely are in the radio. End fed 9:1 58ft wire and 17ft counterpose wire touching ground. On our next windy free day, AA1F and . are easily converted to half wavelengths by the famous 468/f generally Winding 1:64 Matching Auto Transformer on the FT240-43 core. /Type /Pages EFHW unun Resonant Long Wire 49:1 Transformer With BNC or SO-239 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). presents an extremely high impedance to the tu /Filter [ /FlateDecode ] It will be good for 15m, and 10m. %PDF-1.5 49:1 vs. 9:1 Transformer for RX only? - RadioReference.com Forums Experimenting with 1:64 and 1:49 end-fed antenna Ununs on - reddit 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. Tweak the antenna length if necessary and then maybe adjust the turns ratio again. There are numerous configurations available online that will accomplish this on multiple bands (Google search "end fed half wave antennas"). EFHW unun Resonant Long Wire 49:1 Transformer With BNC or SO-239 | Mobile Phones & Communication, Radio Communication Equipment, Antennas | eBay! It is important to use a counterpoise. The Short Answer Would Be That an UnUn Is a UN balanced to UN balancedmatching transformer. 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 . this The graph below shows lengths to avoid for different collections of bands. License Study The ratio doesn't need to be 49:1 2,400 ohm either, other ratios will transform to other impedance. endobj I have not done this yet. 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. Antenna") is an 84' long end fed and a 17' long counterpoise (6.5' for 20m). <> 3 0 obj 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. Hopefully these random wire length calculations will help us all make this "easy" antenna work better! endobj Mike ab3ap, Editors note: Many thanks to Jack, VE3EDD (SK)and Mike, AB3APfor sharing their math and computerskills with us. Allows the internal tuner of most rigs to tune remotely mounted single wire antennas. /Type /Catalog Wire lengths for the 4:1 ratio in models 4130, 4132, 4134, 4932 and 4935. Scott builds a compact random wire antenna with 9:1 Unun Figure 3 Wiring of the 9:1 voltage unun. In fact, the 9:1 unun that I built is actually an autotransformer. If you plan on stringing up a dipole you use 2 equal lengths of wire with the Balun in the middle. Both were on 20 meters at 97 watts, Icom 7300. The management works very hard to make sure the community is running the best software, best designs, and all the other bells and whistles. 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. End Fed Half Wave Antenna Coupler (EFHW) - M0UKD high the other 1.5m (4.5feet). A level of 500-600 watts is the maximum with a further reduction onany band measuringabove 3:1. An Unun is used to match an unbalanced line to another unbalanced line. /Resources << Part List: ?7{*. When on the trail, at Field Day, or whenever a good antenna is Re: 9:1 or 49:1 unun for end-fed long/random wire? Well, I didn't think it would make any difference at that many multiples. 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. 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. A way of connecting the analyzer to the transformer. Continue twisting the entire length of the short wire. 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. endobj and experiment. 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. Thus a 1/4 wave for 20m@16ft, 40m@33ft as examples are not going to work. The vertical (y-) axis shows the VSWR and the horizontal (x-) axis shows the frequencies. For a better experience, please enable JavaScript in your browser before proceeding. You need to use these lengths and the longer ones . You will also need a half-wavelength length of wire (14 or 12 gauge typically) in order to construct an antenna radiator for whichever ham band you choose. 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. That's it in a nutshell..or is it? I sent him the link to the 49:1 unit to get his feedback. The most common question I get asked is what is the correct length for my End Fed Long Wire Antenna? 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.). 1 0 obj 1:64 vs 1:49 balun for an end fed?? : r/amateurradio - reddit PVC Junction Box(Home Depot), 1 x 1/2 in. The other is to provide strain relief for the antenna wire). PDF Construction Details 49:1 Un-Un For End-Fed Resonant HalfWave Antenna While these lengths have been shown to work well on many bands, which Best SWR was . The unun was floating at about 15 feet above ground. 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. X:nzf4p:t;r }~_HOZcX:^$* J^XZuu|"nX/Wkw0hA>y1(z2+v_Xzu[/:^$*m*>hk_:+c{ stream The beauty of the halfwave antenna is it's a complete antenna in the sense it needs no counterpoise. An UNUN is needed to match the high impedance of an end fed antenna (2k-4k ohms range). Midi Music Tools Ham Radio News! This design is excellent for matching both long and short length wire antennas for multiband use. Our newdesign isperfect for matching both long and short length wire antennas for multiband use. The bandwidth where SWR was below 2:1 was about one MHz. Ham Radio Videos! So is an essential piece of gear to have. want the antenna to be at least 1/4 wavelength long for each band you 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. There probably should be some holes for ventilation. Presented for your consideration by Jack, VE3EED. 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 transformer is designed to be used with an end fed half wavelength of wire only. The length should be calculated based on the lowest frequency to be worked. A 50 foot run of RG-8X coax connected the antenna into the LDG Z100-plus tuner and then a Yaesu FT-891A transceiver. (Note: I am not satisfied with this part of the project, so I will describe it here briefly. google_ad_height = 600; /Pages 3 0 R 35. thank you. u?X`f0&/Ri;W0Tn_*TX:ug 9:1 Unun 1.5-54MHz 2kW 9132S. You also Allows the internal tuner of most rigs to tune remotely mounted single wire antennas. I attached the toroids to a PVC DWV test cap with 3 cable ties. 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. 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. the C code, in Matlab or Octave get a plot by simply putting the Turns 1 through 14 are secondary windings (the long wire). rig, often with no feedline, and the other end in the air attached to Therefore, we came up with the following numbers to avoid (IN FEET): These lengths in the table beloware the culprits that cause all of the trouble when using random lengths. It's an efficient way to get all the multiples SO-239 connectors are silver plated with Teflon insulation. Random Wire Antenna Lengths - University of Delaware 4 x 4 x 2 electrical junction box (available at big box hardware stores), One PVC DWV Test Cap (available at big box hardware stores in plumbing). 1936 article, however, fall in line with 468/f and so is used here. Downward impedance transformation by factor of 49. 49:1 UNUN IMPEDANCE XFORMER FOR END FED HALF WAVE ANTENNA. hb```YloD@(aKI V!}g@~}%Q/[[~_=Wy-:O)x[~hs/~SGeG _QE C6q %r %PDF-1.4 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 imported my spools from the US, but I have seen them on Ebay in the UK. So for example 80m could range in length from 120 to 133 feet. The 49:1, shown in my previous message, is meant for the EFHW that are fed close to or on the half wave (highest impedance) point. The most important length is one that is non-resonant on any band. Bullet 50:450 (9:1) HF Unun, 1.8-61 MHz, 1500 Watts, End Fed Antennas. /Name /Im0 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. transmit frequency the impedance is so high that tuners in most rigs He had heard good things about 'Balun Designs' so he recommended you. http://udel.edu/~mm/ham/randomWire/. 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. 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- Cut the ground wires (free twisted short and long wires) of the unun to the correct size, scrape the enamel insulation off of the free end with a box cutter, and add a ring terminal. google_ad_slot = "1982258389"; Use a slide rule! <> 33 ft #18 insulated copper wire (20m half wave), Counterpoise: 1 meter coax (0.05 x wavelength) connected between 64131 and Balun Designs 1115d Isolation /Choking balun, 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. Suggested wire lengths for 1-61 MHz operation (measured from Bullet wire point): Bands Covered (meters) Wire Length (feet) Minimum Coax Length (feet) 40-30-20-15. However, the radio didn't tune up very well on 15 meters. 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. 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. Here is an ARRL often can't match it. ones 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. Each vertical blue line represents an amateur radio band. The 9:1 may work best with that length wire and a tuner, but some say that length is undesirable for the hf HAM bands. . Nelson Antennas 9:1 balun - eHam.net Proudly powered by WordPress 49:1 UNUN Transformer 2 Kw 160 - 40 m - Wire Antennas 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. 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. 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). These are sometimes known as a Magnetic Longwire Balun. Electronics AndWhat Is It Used For In Antennas? =======================, 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: For example, This is a followup video to #344 where I assembled the 49:1 UNUN kit from HF-Kits / ARRL. /Height 752 Here Is a 250 Watt Home-Brew That I Made In about an Hour. I have included a screenshot showing the stations that reported spotting my 200 mw beacon over the last 16 hours. 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. That meant calculating all the way to 32 multiples of a half wave on 10 meters. The "Super Bullet" End Fed Long Wire Antenna Matcher - 1500/3000 watt rated for Super-Punch of your signal! However, the list has been revised and is good for wires as long as 500 feet. 2. 25 0 obj <> endobj These dimensions were derived from modelling the antenna in EZNEC. SBULLET-9U-1500. 22.00 + 5.00 Postage. End-fed wire antenna lengths - Amateur Radio Stack Exchange google_ad_client = "ca-pub-9377297764300878"; The length of a half wave antenna is calculated using the following formula: L (ft) = 468 / f (freq in mhz). I connected it to a 33 wire running from my balcony, through the trees, and ran WSPR overnight to check things out. <>/ExtGState<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 612 792] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> 1 0 obj endobj 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. which got me thinking. At this point, Ive only used the 49:1 tap, but plan to take the 64131 whenever I operate portable. 6 0 obj Balun One Nine v1 - Tiny Low-Cost 1:9 HF Antenna Balun and Unun with What Is an End-Fed Half-Wave (EFHW) Antenna? - OnAllBands 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. Then verify it with your installed antenna and SWR measurements. << 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. You'll want to have that wire up as high as you can get.. Windings are inserted into Teflon tubes increasingtotal breakdown to 10,000 volts. 49:1 Impedance Transformer for EFHW Antenna - DX Explorer random wire should use 423/f. Superglue 2 toroids together. To DB's point of a single band antenna, this 49:1 transformer is a good choice for a single band matcher. This article details the construction of the transformer. % 3. endobj 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. >> 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. Here they are in order: gnuplot You can take one of these 49:1 transformers and use the 468/freq (Mhz) formula to calculate the length you need in feet. Ham Radio End Fed Antenna with a 1:64 Matching Network Swr usually is all over the place and the tuner will just not do it's job. Moving the pot up and down gives a feel for the SWR versus antenna impedance sensitivity. (QST, Oct 1926, "The Length of the To summarise the results WRT to reference antenna consisting of 30ft wire vertical fed with auto- Support The Site stream The 49:1 End Fed Half Wave Antenna is very popular choice for home & field use, Ideal for limited space and stealth applications. This antenna, which works on 10, 15, 20, and 40 meters, has a very high impedance of around 2,500 Ohms. >> /Kids [ 4 0 R ] so that it is not a halfwave multiple of any frequency you want to use. https://elginradio.wordpress.com/2017/10/17/end-fed-half-wave-antennas/. This undesired reflection of RF power back toward the transceiver is identified as a high voltage standing wave ratio (VSWR or SWR). config file by typing gnuplot rw.gnu. q Drill out holes in the designated bottom of the electrical junction box for the SO239 chassis mount. a more capable tuner - see AA5TB's 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. When you're antenna (or radial) length's an odd multiple of the operating freq, you may not need a balun or even a transmatch. FCC Information Superior Essex Heavy build polyamideimide. Just add or subtract as needed a little at a time toget the best compromise. This project assembles a 49:1 ferrite-core ("FT") type #43 transformer that matches 50 ohm input to 2500 ohm end fed 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. Home-brew End-Fed 49:1 UnUn. - KA9QJG Repeaters Drill another hole in the same side as the antenna radiator wire mount hole. stream 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 /CropBox [0 0 748 752] 1 0 obj 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. Y &lD30. The counterpoise wire, This transformer is designed to be used with an end fed, Approx. 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. Shortwave Listening (Also check out AB3AP'Swebsite and say thanks for sharing his skills. The kit includes the parts needed to construct a 49:1 impedance matching network, which will transform the impedance to 50 Ohms, which will suit most transceivers. Solder a the 100pF capacitor between the center conductor wire and ground wires.

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