49:1 unun wire lengths

a more capable tuner - see AA5TB's The graph below shows lengths to avoid for different collections of bands. 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. Make sure the beginning few inches of twisted wire is not involved in the winding (i.e., just hanging down from the toroid). Connect this ring terminal to one of the SO239 chassis bolts. Some of these numbers are too close to squeeze in between them. Enclosure Height: 5.000 in. used by hams for dipole lengths. This was 9m vertically metres up a fishing pole and then about 5.8m out. My homemade 49:1 EFWH with a 60 wire (cut for 40M) would do just fine! Alternate connectors and Mounting Options are available in the. 0$Ve 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. Figure 2 Schematic of the 9:1 voltage unun . Post Reviews These are sometimes known as a Magnetic Longwire Balun. Designed for those who want the maximum isolation and choking across the full HF spectrum. 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? 0 A way of connecting the analyzer to the transformer. 49:1 UNUN IMPEDANCE XFORMER FOR END FED HALF WAVE ANTENNA. When do you use a 1:1, 9:1 or a 49:1 balun? The unun was floating at about 15 feet above ground. Our newdesign isperfect for matching both long and short length wire antennas for multiband use. UJM-49-1 $56.99 Save up to 6% when you buy more. 3 to31 MHz - up to 1kW intermittent (50% duty cycle). Tweak the antenna length if necessary and then maybe adjust the turns ratio again. 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. http://udel.edu/~mm/ham/randomWire/. I sent him the link to the 49:1 unit to get his feedback. Modify bands and endobj It is important to use a counterpoise. In stock . "Just received my new 64131 yesterday and was anxious to see how well it performed. the program as I did, above, for my K1. We'd really appreciate it! HF & Shortwave 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. AndWhat Is It Used For In Antennas? /BitsPerComponent 8 Here's a list of recommended lengths of wire to use with a 9:1 unun. Kj8~q7c? For typical tuners built into a rig, In another life, I could have been a telephone engineer. 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.). all US ham bands. , This is a partial reprint (with permission) of an excellent series of articles published by KV5R I did not want to put the transformer in the housing until I tested it. u?X`f0&/Ri;W0Tn_*TX:ug 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 . "Here's the word on random-wire antennae.". /ColorSpace 11 0 R 2. You also Ham Radio News! CQ-Calling All Hams! endstream endobj startxref 22.00 + 5.00 Postage. I plotted the results for the U.S. CW band edges for use with my4 band Elecraft K1 qrp rig. 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. 2 0 obj To summarise the results WRT to reference antenna consisting of 30ft wire vertical fed with auto- However, the list has been revised and is good for wires as long as 500 feet. /XObject << /Im0 9 0 R >> I have never tried to transmit through it, but it proved the optimal ratio for receiving with my setup. The table below represents half wave lengths and multiples that you DO NOT WANT TO USE! So for 80 meters (say 3.525 MHz) this gives you about 133' of wire. Lengths to avoid are not always the same as So for example 80m could range in length from 120 to 133 feet. 5 0 obj Drill another hole in the same side as the antenna radiator wire mount hole. Hopefully these random wire length calculations will help us all make this "easy" antenna work better! I included the tools I used to analyze the transformer as well; this is only necessary if you are interested in analyzing your project. are blocked out because an antenna should be at least that long. Advertising Info Even easier than Continue on winding the long wire through the toroid to complete loops 3 through 14 as shown in the schematic below. Use with other lengths can potentially damage the transformer depending on power level in use. Here they are in order: The Short Answer Would Be That an UnUn Is a UN balanced to UN balancedmatching transformer. << x 2 in. As an example, a 28-31 foot wire will typically allow 40 thru 10 meter coverage and a 43-50 foot wire will provide access to 80 thru 10 meters. Site Map NOTE: Rewording the previous paragraph, if you have a capable enough Stacked coreswithwinding configured as 49:1auto transformer. endobj My commercial EFHW is 130 feet long for 80 and up, and my 40 meter homebrew antenna is about . This type of antenna is very easy to install because there is no need . Recommended wire lengths for Unun models 9130, 9132 & 9135 Table shows typical SWR relative to installed wire length. Humor Ham Satellites I use this 8010 EFHW at home, too. Step 1: Drill holes for and install the SO-239 or BNC connector, the stainless steel machine screw antenna connector and the ss machine screw ground connector. =======================, 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: In addition to multiples, So a 49:1 impedance transformer is needed to match the 50 ohms of the coax at the feed line. EFHW unun Resonant Long Wire 49:1 Transformer With 67' Antenna Wire. 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. I say run what you got and don't worry about it. Each winding is counted when the wire enters through the center hole of the toroid. 49:1 or other high ratio transformers are for resonant "cut to frequency" antennas like the traditional zepp/fuchs antenna. This is a followup video to #344 where I assembled the 49:1 UNUN kit from HF-Kits / ARRL. (A t0 B) Fold over 6 to 8 inches and twist it together. 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. Reading Room End fed 9:1 58ft wire and 17ft counterpose wire touching ground. >> Drill a hole in one side for the antenna radiator wire mount (for a #8 bolt in my build). ?7{*. Balun Designs. I used 2000 and 1000 ohm resistors in series connected to the proper unun wires with alligator clips for a total of 3000 ohms. 6 0 obj var sc_security="1df091cc". I made one without doing this and it didn't work so well. That's it in a nutshell..or is it? The length should be calculated based on the lowest frequency to be worked. 9:1 UnUn End Fed Long Wire Lengths - Pretty Simple. Shortwave Listening 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. Ask Elmer See the picture below. %PDF-1.7 well, the main antenna wire goes to the 9:1 UnUn "+" connector, the vertical counterpoise (insulated !) 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. recommended on VE3EED's page because I use all halfwave Start winding the Matching Auto Transformer, each pass through the center of the core equals one turn. SSTV So, having nothing better to do one day, I re-did the calculations going out to 500 feet. The 49:1 End Fed Half Wave Antenna is very popular choice for home & field use, Ideal for limited space and stealth applications. 1936 article, however, fall in line with 468/f and so is used here. 27.00 (27.00/Unit) Free Postage. 25 0 obj <> endobj 1 0 obj Anyway, an old friend mentioned 'MyAntenna.com' but they were closed for the summer. Repeater Basics 8 0 obj << The graph below shows lengths to avoid for different collections of bands. We do not encourage any radio operations contrary to regulations. A 50 foot run of RG-8X coax connected the antenna into the LDG Z100-plus tuner and then a Yaesu FT-891A transceiver. 74 0 obj <>stream 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). <> 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. Free Postage. Ultimately, this housing works fine, but it is heavy and clunky.). Hi guys,not really hfu related,but I tought I might ask here as I have my account. endobj 40-30-20 . I actually did this first and before the connector was bolted to the box. Electronics 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). 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 . June 8, 2022 at 9:17 am. However, the radio didn't tune up very well on 15 meters. UNUN 9:1 or 4:1- 3kW ICAS This is is dual 9:1 and 4:1 UNUN used for popular "non-resonant" length END FED wire antennas or verticals like 27 or 43 feet. 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. /CropBox [0 0 748 752] This Balun Designs unit is replacing an MFj 1982 HP EFHW balun that was DOA when it arrived last May. You are using an out of date browser. REVISED: 16 19 22 26 32 33 38 44 46 48 52 64 65 66 76 78 80 88 92 95 96 99 104 110 112 114 123 128 130 132 133 138 144 152 154 156 160 165 171 176 182 184 190 192 195 198 208 209 220 224 228 230 231 234 240 242 246 247 256 260 264 266 272 276 285 286 288 297 304 308 312 320 322 323 325 330 336 338 342 352 361 363 364 366 368 369 374 380 384 390 396 399 400 414 416 418 429 432 437 440 442 448 455 456 460 462 464 468 475 480 484 494 495 496. 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. bands you're intested in in a vector like the example below, by typing. Presented for your consideration by Jack, VE3EED. In fact, the 9:1 unun that I built is actually an autotransformer. often can't match it. <>>> 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. 73, 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. <>/ExtGState<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 612 792] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> endstream >> Well, I didn't think it would make any difference at that many multiples. presents an extremely high impedance to the tu Power Handling (CW/SSB): 100 W/200 W Enclosure Width: 2.500 in. The WorldwideDX Radio Forum was originally established in 2001. /Type /Catalog << the C code, in Matlab or Octave get a plot by simply putting the This design is excellent for matching both long and short length wire antennas for multiband use. Be sure to review the various lengths in the link below to obtain the lowest SWR across most if not all HF bands. EFHW unun Resonant Long Wire 49:1 Transformer With BNC or SO-239 | Mobile Phones & Communication, Radio Communication Equipment, Antennas | eBay! . 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). 10C) for the 10-80 m bands, or even 6-160 m: 17 ft (5.2 m) of twin-lead and 68 ft (20.7 m) of antenna wire (i.e., standard dimensions). Wire lengths for the 4:1 ratio in models 4130, 4132, 4134, 4932 and 4935. /Resources << 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. endobj x 4 in. For calculating the length of a half wave in metres, I use 141 (MHz) for wire elements. Bullet 50:450 (9:1) HF Unun, 1.8-61 MHz, 1500 Watts, End Fed Antennas. Wire-Lengths-for-9-1-ununs.pdf Created Date: 12/12/2022 11:20:42 AM . 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.

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