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

1 0 obj 73, Thank you so much for such a great product! 5 0 obj June 8, 2022 at 9:17 am. The "Almost Random" Wire Antenna - KB6NU's Ham Radio Blog Save program output in file named 'f', and use config file by typing gnuplot rw.gnu. 31 /Type /XObject 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. %%EOF They just saved you and I loads of time and frustration. 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. 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. Site Map 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. V#X~[Z?\ZcX:-Y?&Y?IqTnayZ{jTZOub}=UTWu1G>o.,RaT c=W>:sECXTkc=X Super Bullet Features: - Uses proprietary broadband impedance transformer design for maximum bandwidth with SWR < 2 from 1.8-61 MHz for 1500 Watt model and 1.8-30 MHz for 3000 watt model 40-10m with a 49:1 Unun. /Filter [ /FlateDecode ] . 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- 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. License Study 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. stream The unun was floating at about 15 feet above ground. https://elginradio.wordpress.com/2017/10/17/end-fed-half-wave-antennas/. Ham Radio Videos! The Short Answer Would Be That an UnUn Is a UN balanced to UN balancedmatching transformer. (Note: I am not satisfied with this part of the project, so I will describe it here briefly. 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. Antenna") is an 84' long end fed and a 17' long counterpoise (6.5' for 20m). plan to use. >> ones That's it in a nutshell..or is it? >> "The Simple Build" 64:1 EFHW antenna transformer (UnUn) I'm not saying aliens are in the radio, but aliens definitely are in the radio. Hope it's clear now, if not. Nelson Antennas 9:1 balun - eHam.net Wire lengths for the 4:1 ratio in models 4130, 4132, 4134, 4932 and 4935. Ultimately, this housing works fine, but it is heavy and clunky.). Just an FYI that I thought you might be interested in. Designed for those who want the maximum isolation and choking across the full HF spectrum. 3 0 obj 75/80 METER RESONATOR KIT FOR THE UJM-EFHW-40-10 200W 40-10m ANTENNA I used 2000 and 1000 ohm resistors in series connected to the proper unun wires with alligator clips for a total of 3000 ohms. (wlSR9dJ_x%+VHX4FRr 3>;g^x%g'wkJu,i~#Q"2|WGf[!_m]#&1$)R.{--" 'dGO;=_B$T}". 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. Theme designed by Papathemes. VSWR analysis of the antenna in the field showed that VSWRs between 3-5.5 from 40M to 10M. 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. LDG Electronics RU-9:1 Unun RU-9-1 - DX Engineering Random Wire Antenna Lengths - University of Delaware Twist the short and long wires together starting at an end of each wire. Jack, VE3EED, used center frequencies of thebands described in the article above, and I thought it would be nice to use band edges. 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. 0 Using a 49:1 transformer shoot for the best 50 match @ appx 2450 load over your working frequency bands. These are sometimes known as a Magnetic Longwire Balun. 9:1 or 49:1 unun for end-fed long/random wire? That meant calculating all the way to 32 multiples of a half wave on 10 meters. You also (Center fed is so appealing because you avoid this.). 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 swept the VSWR of the unun and resistors as described from <1 to 55MHz. Drill another hole in the same side as the antenna radiator wire mount hole. /Creator (XnView) Do what works best! Allows the internal tuner of most rigs to tune remotely mounted single wire antennas. endobj 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. Designed for use with single wire unbalanced antennas, this new addition is small, compact and perfect for quick portable/emergency installations. This is not exactly a 1/2 wavelength in free space, but works for wire as it has a different velocity factor than "air". and experiment. End Fed Half Wave Antenna Coupler (EFHW) - M0UKD That is the 10th multiple of a half wave on 15 meters. Enclosure Height: 5.000 in. (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. Usually any wire length that is non resonant, like those shown above, will work with the 4:1 ratio. excellent page for EFHW info - or, addressed below, to cut the wire So, having nothing better to do one day, I re-did the calculations going out to 500 feet. Modify bands and Typically unbalanced = 50/75 ohms too unbalanced = 450/675 ohms. 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 . 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. You can get good loading and low swr on sometimes 2 or 3 bands, but one or more of the bands thatyou want, just will not cooperate with an swr that can be adjusted with the "tuner". PDF 33ft Verticals and 4:1 Ununs - G8JNJ The vertical (y-) axis shows the VSWR and the horizontal (x-) axis shows the frequencies. If the choices are. A way of connecting the analyzer to the transformer. FCC Information Use only the white gaps for your antenna lengths, and if Weight: 0.380 lbs. Bullet 50:450 (9:1) HF Unun, 1.8-61 MHz, 1500 Watts, End Fed Antennas 9:1 Unun EF Random Long wire matching Transformer with BNC or SO-239. The most important length is one that is non-resonant on any band. endstream endobj startxref 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. 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. Thus a 1/4 wave for 20m@16ft, 40m@33ft as examples are not going to work. uR5I5z G^u2`j[}+sy9 installed, it is a compromise antenna but great for portable use because We'd really appreciate it! Both were on 20 meters at 97 watts, Icom 7300. Product Reviews The management works very hard to make sure the community is running the best software, best designs, and all the other bells and whistles. Drill a hole in one side for the antenna radiator wire mount (for a #8 bolt in my build). IMG_2.jpg Step 2: Take the 6 feet of 18 gauge enameled copper wire, measure 11" from one end and fold it back. %PDF-1.5 is that for a given ham band there are min and max frequencies which I purchased a MFJ-16010 Random Wire Tuner and an LDG RU 1:1 unun. these are the worst lengths and you want to be as far from colored 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. The trick, therefore, is either This type of antenna is very easy to install because there is no need . This article details the construction of the transformer. <> My homemade 49:1 EFWH with a 60 wire (cut for 40M) would do just fine! Legal Stuff Contact Use with other lengths can potentially damage the transformer depending on power level in use. I won't bore you with all that so the first portion of this still only shows up to the 4th multiple. SSTV 9:1 UnUn End Fed Long Wire Lengths - Pretty Simple | ve3ips The length should be calculated based on the lowest frequency to be worked. /CropBox [0 0 748 752] Start winding the Matching Auto Transformer, each pass through the center of the core equals one turn. This project assembles a 49:1 ferrite-core ("FT") type #43 transformer that matches 50 ohm input to 2500 ohm end fed antenna. Balun One Nine v1 - Tiny Low-Cost 1:9 HF Antenna Balun and Unun with . Support The Site 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 . Repeater Basics multiples, and of course different band combinations yield different The bandwidth where SWR was below 2:1 was about one MHz. << This transformer is designed to be used with an end fed half wavelength of wire only. We hoisted the free end of the antenna wire approximately 30 feet into a tree. 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.). So for 80 meters (say 3.525 MHz) this gives you about 133' of wire. an auto-tuner at the base vs. the same antenna fed a 4:1 balun wound with 75 ohm coax on two separate type 43 ferrite cores and a remotely sited tuner fed via 200ft of low loss LDF2-50 coax vs. a broadband antenna of the same element length. The 49:1 impedance transformer will help you bring down the high impedance of your resonant EFHW antenna to almost 50 Ohm. /Kids [ 4 0 R ] https://elginradio.wordpress.com/2017/10/17/end-fed-half-wave-antennas/. I connected it to a 33 wire running from my balcony, through the trees, and ran WSPR overnight to check things out. Jack, VE3EED - SK. /Type /Pages 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. An Unun is used to match an unbalanced line to another unbalanced line. Use a slide rule! In another life, I could have been a telephone engineer. 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. 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. He had heard good things about 'Balun Designs' so he recommended you. 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. Post Reviews 3 0 obj (Also check out AB3AP'Swebsite and say thanks for sharing his skills. %PDF-1.7 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. /Producer (XnView, http://www.xnview.com) 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. rig, often with no feedline, and the other end in the air attached to Playing with end-fed wire antennas and 9:1 ununs Having the option to switch rapidly between 49:1 and 64:1 should prove to be a really nice feature.. which got me thinking. 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. Wire Lengths For 9-1 Ununs | PDF | Electricity - Scribd STORE 27.00 (27.00/Unit) Free Postage. If you want a single band portable antenna you can mount pretty much however, look up this design. google_ad_client = "ca-pub-9377297764300878"; The QRP End-Fed Half-Wave Antenna 49:1 Transformer Building a great impedance transformer for Ham Radio end-fed wire antennas. The WorldwideDX Radio Forum was originally established in 2001. 0$Ve For example a 32 foot length is actually a half wave on 20m with an impedance of about 3500 ohms and requires a 50:1 balun. (QST, Oct 1926, "The Length of the After winding #2 is made and extends down the backside of the toroid, untwist the wires. (A t0 B) Fold over 6 to 8 inches and twist it together. 9:1 or 49:1 unun for end-fed long/random wire? The 49:1 End Fed Half Wave Antenna is very popular choice for home & field use, Ideal for limited space and stealth applications. 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 . I have included a screenshot showing the stations that reported spotting my 200 mw beacon over the last 16 hours. Wire-Lengths-for-9-1-ununs.pdf Created Date: 12/12/2022 11:20:42 AM . This is to avoid the antenna radiator from acting like a resistor, and thus instead of radiating radiofrequency energy produced by the transmitter, sending it back down the coax toward the transmitter. Alternate connectors and Mounting Options are available in the. 49:1 or other high ratio transformers are for resonant "cut to frequency" antennas like the traditional zepp/fuchs antenna. How to Make a Balun or Unun : 3 Steps - Instructables There are so many new frequencies to stay away from, that it gets pretty tricky for the longer wires. #347: Quick test of the 40m Halfwave End-Fed antenna using a 49:1 However, the list has been revised and is good for wires as long as 500 feet. 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. 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. something as high as you can find. google_ad_width = 160; Ham Satellites Coverutilizes integralneoprene gasket for weatherproof integrity. q /Pages 3 0 R Shortwave Listening Random wire length for 9:1 unun - fairlawnarc.groups.io endobj For instance, to work 40m be sure the antenna is at least 10m or 33' long. Random Wire Antennas - Best Lengths To Use For Random Wire /Length 10 0 R End Fed Antennas - Elgin Amateur Radio Society AndWhat Is It Used For In Antennas? Just add or subtract as needed a little at a time to get the best compromise. Re: 9:1 or 49:1 unun for end-fed long/random wire? See the picture below. We pride ourselves on welcoming Radio Hobby enthusiasts of all types, while offering unbiased, informative, and friendly discussion among the members. recommended on VE3EED's page because I use all halfwave Let's have a look at a few details on how to build a 49:1 impedance . >> Kj8~q7c? /Title (Wire-Lengths-for-9-1-ununs.pdf) is helpful if you're in a hurry to get on the air, read up on the topic You need to use these lengths and the longer ones . 9 0 obj >> Custom mix low permeability ferrite by Fair Rite Products for maximum bandwidth. Humor doing the initial 468/f on C and D scales. . for your country and favorite modes of operation. The Short Answer Would Be That an UnUn Is a "UN balanced to UN balanced" matching transformer. Let the now free end of the short wire hang down from the toroid. There are numerous configurations available online that will accomplish this on multiple bands (Google search "end fed half wave antennas"). The 30 day return period lapsed before I could get the antenna deployed to test it. it is easy to pack and easy to install. Moving the pot up and down gives a feel for the SWR versus antenna impedance sensitivity. /Subtype /Image In fact, the 9:1 unun that I built is actually an autotransformer. thank you. The short piece is for the primary winding of the transformer, and the long piece is for the secondary winding of the transformer. so that it is not a halfwave multiple of any frequency you want to use. 49:1 UNUN IMPEDANCE XFORMER FOR END FED HALF WAVE ANTENNA. Some of these numbers are too close to squeeze in between them. 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. SO-239 connectors are silver plated with Teflon insulation. Hertz Antenna" shows in line 2 of the table that a similarly installed , Most matching problems occur when the antenna system DIY 49:1 Unun Impedance Transformer For End-Fed Half Wave (EFWH /Type /Catalog 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. 6 Screws/ Nuts/ Washers/Wing Nuts And Ring Connectors, 1 X Mica Capacitors 100pF 500V 5%(Mouser Electronics), 1 x 4 in. 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. This antenna, which works on 10, 15, 20, and 40 meters, has a very high impedance of around 2,500 Ohms. 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 . 49:1 UNUN Transformer 2 Kw 160 - 40 m - Wire Antennas So for example 80m could range in length from 120 to 133 feet. EFHW unun Resonant Long Wire 49:1 Transformer With BNC or SO-239 | Mobile Phones & Communication, Radio Communication Equipment, Antennas | eBay! On our next windy free day, AA1F and . bands as possible. 3 0 obj 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. Connect this ring terminal to one of the SO239 chassis bolts. endobj End Fed Long Wire Antennas - Palomar Engineers The key is you want to stay at least 1/2w long but not near 3/4w for any band of interest. 49:1 EFHW Antenna 40-10M 100W - M1ECC-Antennas endobj the program as I did, above, for my K1. A 9:1 unun is a transformer that reduces the impedance at the input by a factor of 9. 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. 6 0 obj 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. Balun Designs. It's an efficient way to get all the multiples x@ http://udel.edu/~mm/ham/randomWire/. That type of wire antenna could be lower than 50 ohms at some frequencies and over 2,000 ohms at . "Here's the word on random-wire antennae.". x 4 in. Figure 2 Schematic of the 9:1 voltage unun . PDF Recommended wire lengths and Installation Notes for Unun models 4932 /CreationDate (D:20221212112042) Turns 1 through 14 are secondary windings (the long wire). 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. 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. this As typically Mike ab3ap, Editors note: Many thanks to Jack, VE3EDD (SK)and Mike, AB3APfor sharing their math and computerskills with us. One end goes straight into the 10m or 33' long. Here they are in order: Liquidtight NM 90-Degree Connector(Home Depot). Bullet 50:450 (9:1) HF Unun, 1.8-61 MHz, 1500/3000 Watts, End Fed Long /ModDate (D:20221212112042) InJack's own words. stream 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. Picture Information. I made just a touch over 100 QSOs today with the new unit. 2 0 obj This is a 4:1 Current Balun.That means it can match a 200ohm antenna to a 50 feed line. 748 0 0 752 0 0 cm SWR was good after cutting the wire to appropriate length. We are working every day to make sure our community is the best Radio Hobbyist's site. Experimenting by slightly changing the wire length (+ or-) is encouraged to provide best overall performance. Part List: 3. =======================, 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: /Parent 3 0 R 9:1 UNUN - MyAntennas.com The ratio doesn't need to be 49:1 2,400 ohm either, other ratios will transform to other impedance. 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. What these lengths are depend on your tuner and also the wire's surroundings and also the ground system. 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 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. Our newdesign isperfect for matching both long and short length wire antennas for multiband use. random wire should use 423/f. 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. are easily converted to half wavelengths by the famous 468/f generally 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 . << Recommended wire lengths for Unun Balun - Webclass.org results. Presented for your consideration by Jack, VE3EED. Please note that I will not be describing the construction of the antenna wire radiator here. %PDF-1.4 Prescott Hamfest - W7YRC Lengths of a half-wave or multiple must be avoided. To summarise the results WRT to reference antenna consisting of 30ft wire vertical fed with auto- Turns 1 & 2 are primary windings (the short wire). endobj $1YacO5Q}YC\>qZ } Lengths to avoid are not always the same as The counterpoise wire, This transformer is designed to be used with an end fed, Approx. x {avla[g#+yt]Mk"B` xp[AO8;c=\b}|8p4cSmzgU7be,+i5ci6uq.x T/s@9uk-oZX;u`=U >8rsIXW B:uUVr6a] endobj Well, I didn't think it would make any difference at that many multiples. W3EDP's results in the above referenced Longer wire is always more Power Handling (CW/SSB): 100 W/200 W Enclosure Width: 2.500 in. 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. 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. /MediaBox [0 0 748 752] Theme: Newsup by Themeansar. wire lengths less than 1/4 wavelength of the lowest desired frequency The graph below shows lengths to avoid for different collections of bands. 73. JACK, VE3EED Scott builds a compact random wire antenna with 9:1 Unun This design is excellent for matching both long and short length wire antennas for multiband use. 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. For calculating the length of a half wave in metres, I use 141 (MHz) for wire elements. 80m up, W3EDP's 84' antenna, 17' counterpoise is probably the way to go. The length should be calculated based on the lowest frequency to be worked. 40-30-20-15m bands for my 4 band Elecraft K1 qrp rig. (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. I took a literally random length of 14 gauge house wire and attached a banana plug to be shoved into the antenna port of the tuner. This transformer converts the impedance at the end . While I have not done so yet, I plan on gluing the test cap to the back of the junction box. 74 0 obj <>stream To DB's point of a single band antenna, this 49:1 transformer is a good choice for a single band matcher. RFI Tips and Tricks var sc_invisible=1; /* Ad banner 160 x 600 */ 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.