Unun for random wire antenna

Unun for random wire antenna. Random wire antenna. An example: if you cut your wire for 40m band, antenna will resonate on 40M One 20 meter long (the right cable in the picture) and one 8 meter long (the down-left). 5 - 54 MHz. 5 - 54MHz - 5kW. Usually any wire length that is non resonant on the band or bands desired will work with the 4:1 ratio. For the counterpoise (s), I have a roll of CAT 5 I set-up my jackite pole today and tried a 68' wire with the 9:1 unun matchbox. Unlike the other Spark Plugs, a counterpoise lug is incorporated into the design. An end fed isn’t really an end fed, but a highly off center fed, off center fed dipole. This makes keeps the weight and bulk down while delivering a very strong antenna element. Radio propagatio A dipole is basically a mono-band antenna. In this two-part tutorial, Paul (OM0ET) show us his new design of a compact 9:1 UnUn for portable QRP Random Wire Antennas. comes from current flowing over a spatial distance along the wire. An old but good multi-ba Here’s a list of recommended lengths of wire to use with a 9:1 unun. Heavy duty 5kW, 4:1 unun designed for use with wire verticals, long wires and multiband monopole verticals. Additionally, we go through the process of building a 9:1 Unun for an EFRW Antenna. Figure 1 Typical ATU and long wire antenna configuration with an earth or earth plus counterpoise. Antennas 101 / How does an antenna work Apr 5, 2023 · April 05, 2023. stainless/ 80-6 meters 150w pep 49:1 unun impedance xformer for end fed half wave antenna. If you have 40-45ft of coax then try the choke 20-30ft from the antenna if Jul 23, 2021 · In this video, we discuss 9:1 End Fed Random Wire Antennas and the use of a counterpoise. Random Wire Tuning. Jan 4, 2019 · These antennas are suitable for both permanent home stations, as well as for field and emergency operations. #1. Here's a simple, inexpensive project that will improve the performance of your random length wire or end fed halfwave antenna. These are based on the use of a sloper configuration with the unun near ground level but final 9:1 voltage unun using a T-200-2 powdered iron toroid core. html#/Heres This is why s. Works with a 4:1 UNUN. You will need a tuner, but with a single antenna wire setup, all the bands can be in your grasp. 450 ohm average antenna impedance to 50 ohm coax, also know as a 9:1 unun). 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. DIY 9:1 Unun End Fed Random Wire Antenna for Ham Radio. --. Feb 7, 2022 · A full review of the Nelson Antennas END FED "RANDOM WIRE" HF DIPOLE 9:1 ANTENNA. Post 2113. $95. Nov 24, 2020 · Thanks to "Stancoyote" for this upbeat, inspirational antenna project for radio amateurs impacted by deed-restrictions on their property (HOA/CC&Rs). The key to making this antenna work efficiently is to add a 9:1 UnUn and a good counterpoise system. Both are extremely well made and perfect for Field Day/POTA/SOTA or any ham radio in the field. Solo antenna mast erecting - Ham Radio know how. Here are some general comments about the antenna from Stan: The “Bullet” End Fed Antenna Matcher 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. You might do better with a counterpoise or other "earth" ground. The end-fed random wire antenna has a 9:1 UNUN designed for use with radios that have an antenna tuner. A random wire antenna is a radio antenna consisting of a long wire suspended above the ground, whose length does not bear a particular Aug 20, 2023 · Watch on. com/thes A random length outdoor wire antenna installed as high above ground - and as far away from buildings and power lines as possible - will generally give quite satisfactory results. Thus the need for a short counterpoise (so 5 to 15% of the antenna is on the other side of the transformer/balun) to optimize The antenna wire is 26 AWG copper clad steel wire with a great “silky” jacket. The 20-ft of feedline connected between the 1:1 Balun and the 9:1 UnUn is composed of an 18-ft length of RG-8X coax which is connected to a 2-ft RG-58 pigtail coming out of the UnUn. I was located in north-east part of Slovakia about 350m a. Thanks to John of the "Amateur Radio On The Air" youtube channel for this helpful accessory for end-fed half wave antennas. 8EC18000-9D66-44E8-8C9A-B6452AC9FFE6. " Here are some of Paul's observations: "I was tested my home brew mini 9:1 UnUn with random wire antenna 17,68m long. Technically a true "longwire" needs to be at least one wavelength long. LDG Electronics RU-9:1 Unun was designed to allow easy interface of random length vertical and end fed antennas to the LDG line of Automatic Antenna Tuners. My advice: don't bother with a "random wire" that isn't resonant. In general, you want to avoid choosing a length that is a half wavelength, or multiple of a half wavelength of a band that you want to operate. How the Longwire or Random Wire Antenna Works. I set it up as an inverted L with about 26 feet vertical and 42 feet horizontal. " Make two of these baluns--one for home use and the other for your mobile "go-kit. The random length wire antenna is one of the most popular antennas available to radio amateurs. An end-fed wire often seems like the simplest type of antenna, but getting it to work well is actually rather complex. Presumably the ferrite toroid works better for the lower bands, 40 and 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. It is designed to convert the impedance of the antenna to a value that is better suited for the transmission lines. Requiring a unun to feed a long wire antenna Oct 27, 2022 · 1. The 9:1 Spark Plug provides 80 m through 10 m band coverage in the familiar Spark Plug form factor. The top wire is the antenna and you can see my first choke and the antenna cable feed. Also the support and customer service is fantastic. However, I figured that with my Elecraft KX1 and KX3 QRP radios both having good internal ATUs, that they have no requirement for a 9:1 impedance drop. Length: The length of the wire is crucial in determining the resonant frequency of the antenna Random Wires. Long / Random / End-fed Antennas. A non-resonant random length wire end fed antenna is one of the simplest and easiest to use HF antennas in the radio amateur's toolbox. However, there is another issue that may require some planning. Jan 24, 2024 · An Unun, short for Unbalanced to Unbalanced, is a type of transformer used in RF antenna systems to match impedance between an unbalanced antenna and an unbalanced transmission line. The key to this outstanding antenna is the use of a homemade 9:1 balun inserted between your feed line and the antenna. Do you mind if I ask? Jan 6, 2022 · The center of the system is a 49:1 unun. Radio propagations was poor. End fed antennas generally need a counterpoise, whether an explicit wire attached to another terminal of their unun, or the shield of the coax leading into the unun, or a totally invisible counterpoise formed by their transceiver system's capacitance to An 80-10 end-fed half-wave antenna can be a very good performing part of an HF station. The random wire with counterpoise (version 2) is a great option for backpacking/camping because it eliminates the need to bring a roll of coax but still gives good performance. This would make an excellent weekend project. Post 2111. I am going to leave the antenna up a few days and make a few contacts. 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 or bought, running the feedline, and all the rest that goes with putting up a more elaborate antenna. Wire lengths for the 4:1 ratio in models 4932 and 4935. Can a non resonant antenna be efficient? It sure can. Jan 13, 2020 · VK2PRC Half Wave End Fed Vertical Antenna for DX. The primary issues are: The impedance varies over a very wide range, depending on the length in wavelengths. but Hams commonly call any end-fed wire a longwire or more correctly random wire antenna. Click this link if you want instructions on This is part 1 of a 4 part video that discussed how to build and test a Multiband Long Wire Antenna, a 9:1 Unun, a 1:1 RF choke, and an Antenna Tuner. I have several toroidal ferrite cores laying around from disassembled power-supplies and such, but the many websites I've visited that show the construction of the 9:1 unun have not specified what type/mixture/diameter of toroidal necessary unun and choke. The "9:1 UNUN" are for random length wire antennas fed at the end. Jan 23, 2020 · In this video, Paul (OM0ET) finishes his new mini 9:1 UnUn and begins testing the device "in the field. 5:1. While listening on a SSB transmission I decided to experiment how reception was impacted by end fed "random wire" hf dipole 9:1 antenna. If you mostly want to run the most popular bands, a 4:1 unun with 55ft on one side and 12ft on the other (a 5/6 OCFD) will be truly resonant, with an SWR low enough to tune internally, on 40, 20, 15 and 10m. A lot of internal tuners are limited as to how large of impedance they can handle. It is sometimes used on its 3rd harmonic with coax, or used multiband as a doublet with balun, ladder line and wideband tuner. 73, Noel W2MSA. RANDOM WIRE ANTENNAS USING THF LDG 9:1 UNUNS. I show you how to build a non resonant random wire antenna with a 9:1 transformer. Spark Plug 9:1 Random Wire Transformer - 100 W. 1. November 15, 2021. The wire used is #14 house wire for the 16-ft counterpoise and #14 copper clad steel wire for the 53-ft section. Over the weekend, I decided to make and test another long/random-wire antenna. You apply a little RF and adjust the antenna tuner to achieve the Mar 12, 2007 · On the HamRadioHelpGroup mailing list, there was a related discussion about the “almost random” wire antenna. #RandomWireAntenna #HamRadio #AmateurRadioLink to some websites I gathered information fro Today I was testing out a ~21 meter long random wire antenna, connected to a 9:1 unun. I built a Random Wire Antenna. A few months later I wrapped up WAS on 12 and 160. The UNUN brings the feed point impedance down closer to the transmitter’s 50 Ohm output impedance. This project will help your HF transceiver cope with the high impedance found in end-fed antennas. The number of variations are endless. Dec 19, 2013 · vk3bq / December 19, 2013. The reason behind this is that - like a tuning fork - an antenna will perform best when its size is close to the wavelength of the radio signals it is meant to capture. How to Feed an End Fed Wire? The Balun or in this case the Unun The end fed wire regardless of its length presents a high impedance to the feedline. Jun 13, 2019 · I was reading your post about end-fed, long-wire antennas, I think it was from 2016. If the intention is to build a ½ wave mono band antenna then it is necessary to attach a 48:1 unun at the feed point given the extremely high impedance. Amateur radio websites and YouTube channels are full of chatter about random-length wire antennas fed with a 9:1 impedance dropping transformer (aka 'unun'). Apr 15, 2019 · The feed point of the inverted-V antenna uses a 1:1 balun to convert between the 50 ohm coax input and the close-to-50-ohms balanced inverted-V. But its performance depends heavily on a well-designed and carefully constructed 49:1 unun, which matches the long wire impedance to within tuning range of operation. For instance, even a standard and neat Inverted-V configuration of the EFHW wire antenna is far inferior in performance to a regular horizontal configuration, let alone other random Basic Description of End Fed Antennas. "Tinker John" (W5CYF) does an excellent job of describing how to build one of these UnUn baluns for end-fed random length wire antennas. Dave C KD2JIP. Dec 11, 2016 · The random wire with a unun is my favorite, but I still use the hamsticks and wire dipoles in some situations because they offer better performance. RF balun designs are most commonly associated with core-and-wire transformers, but can also be realized through coaxial and coupled stripline technologies. October 2011 Complete 1:9 UnUn DIY kit for long wire antennas, with proper strain relief. 30′ Coleman 12AWG 600V flexible wire (or equivalent) (#8) Anderson Powerpole connectors (30 amp). In the Salmon Run Contest last September I made over 200 contacts from a park in a rare county. Random wire antennas are popular choices for amateur radio operators due to their simplicity and versatility. Aug 18, 2022 · (13) That’s it! Your 64:1 impedance transformer (unun) is finished! Time to build the linked endfed half-wave radiator wire. Sep 13, 2021 · Random wire antennas are good antennas if you use a 9:1 UnUn to match the high antenna impedance of the wire to the low impedance of your transceiver. Jul 6, 2021 · Jul 6, 2021. As an example, a 28-31 foot wire will typically allow 40 thru 10 meter coverage Dec 3, 2020 · The step-by-step assembly process is clear and easy to understand. With the view to establish a quick and easy multi-band antenna deployment for portable and camping operations a simple long wire antenna with an earth or earth plus counterpoise arrangement with a 9:1 voltage unun is one possible solution. I have a couple questions about end feds. s. packtenna. Buy the Bullet™ balun or unun of your choice and experience the fun of making your own custom antenna with our convenient wire add-on kits. Long Wire Antenna. #3. FT-140 43 mix Ferrite The purpose of the 9:1 transformer (unun, for an end fed) is to do the bulk of the impedance match, then the tuner trims the rest of the way. A tuner is required to make these types of antennas work. MATERIALS AND TOOLS. Remember an antenna using a 9:1 matcher is meant to use a tuner, whether in your radio or external. Here’s how I did it and my results. A random wire is exactly that—a piece of wire that’s as long as you can possibly make it. l. I read an article posted on a sota forum about random wire lengths and how to choose an efficient length, this article talks about the importance of choosing a Dec 7, 2022 · 99. Palomar Engineers employs a dual core matching system that offers wide bandwidth (1. Hello all. Mar 26, 2022 · For reference, my Random wire on my 9:1 unun has a noise floor on 20m of about S3. Peter does an excellent job of explaining how the LDG 9:1 UnUn fulfills this difficult requirement. This antenna, like all antennas, has it advantages and disadvantage. 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. You can add your own wire or get the complete product from this link EFLW-3K antennas. This configuration allows for easy deployment, as the antenna can be hung vertically, horizontally, or even as a sloper. $59. Tim, N9PUZ notes: 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 or bought, running the feedline, and all the rest that goes Nov 15, 2021 · Random Wire Antennas using the LDG 9:1 UnUn. For non-resonant end fed antennas, the typical feed point impedance is 300 to 600 ohms and a 9:1 impedance transformer (e. Reception was good for several bands, probably thanks to my KX3's internal tuner. I was tested my home brew mini 9:1 UnUn with random wire antenna 17,68m long. This 200 watt Unun also operates as a standalone, meaning that it does not necessarily require a tuner for use on a certain antenna. But the perfor-mance of an end-fed antenna is also very dependent on height above ground. This 4:1 Unun (200-50 ohms) will easily handle 300 watts and covers 1. Please Dec 15, 2021 · Making a 49-1 UnUn for End-Fed Half Wave Antennas. Mar 10, 2016 · The transceiver's antenna connection is an unbalanced BNC jack and the random-wire antenna is, well, a random wire. The behavior of baluns and ununs was introduced in Part 1 of this series, where we established that both these Easy to deploy, heavy and sturdy enough to be thrown over a tree limb with ease and robust enough to run demanding digital modes like FT-8/FT-4, RTTY, and PSK31. Coupled with a 9:1 UnUn, a decent counterpoise system, and an "antenna tuner", you can work the world with a convenient length of wire. 00. Dec 14, 2014 · Interesting piece of hardware for using a random-length wire with an SDR-RTL but there's more to this. We’ll use one with an impedance transformation ratio of 9:1, meaning our 50 ohm input is matched to a 450 ohm Designed for use with end fed wire antennas and multiband verticals, this unun is small, compact and perfect for quick portable/emergency installations. Jan 14, 2020 · This is post 2114 in a continuing series of simple ham radio antennas. 99 save up Jan 30, 2021 · According to "Tinker John" (W5CYF), this basic 9:1 UnUn is easy to make, inexpensive, and will take only a few hours to build. http://www. In an effort to better understand the performance of my ft817 and the ZM-2 ATU, I’ve been exploring different random length wire antennas while camping. John takes us step-by-step through the design, construction, and use segments of this handy, "one-evening project. When installed the wire is supported by buildings or trees using the insulators to prevent a short circuit to ground. QRP Dummy Load With Power Measurement. Jul 1, 2018 · In this video, "Tinker John" (W5CYF) shows us an easy, simple, and inexpensive way to build a 9:1 balun for any random length wire antenna you use. LINKED ANTENNA RADIATOR WIRE FOR 6/10/12/15/17 METERS. Oct 20, 2023 · October 20, 2023. This Mini 49:1 UnUn can be used also as the base point of a vertical dipole antenna with its half wave length. I am planning a non-resonant end-fed using a Palomar Engineers 9:1 unun with a wire length of 135 to 138 feet for 160-80-40-20-17-15-12-10 meters (based on the link below). I admit this was using FT8, but the point is I did it all with basically a single antenna. electric and magnetic induction or energy storage fields. Oct 26, 2021 · October 26, 2021. If you're feeding the unun with coax, the brad is acting as a ground for you, something some makers of these end fed antennas don't tell people. " 9:1 UNUN This type of feed point is used to match the coax to an end-fed high impedance antenna. Both antennas have the nulls in roughly the same direction (N-S). #2 TEST: MINI 9:1 UNUN and 41m long Random Wire A #1 TEST: mini 9:1 UnUn Random Wire home made Anten New Mini QRP 9:1 UnUn and Random Wire Antenna (Par Ham Radio Station Grounding. Jan 2, 2020 · Modified RANDOM WIRE ANTENNA with 9:1 UnUn (part 2) Random Wire Antenna with 9:1 UnUn. I have grounded the pole to the counterpoise screw. MULTIBAND ANTENNA. spreadshirt. Instead of a balun, we’ll use a device that is unbalanced on both ends - the unun. The pole have a good ground connection to the earth, you need this for better performance. These can be either ½ wave resonate wires or random end fed wire antennas. . However, to get the most out of your random wire antenna, there are a few tips and techniques you can follow to optimize its performance. Thanks to Peter (G3OJV) of the "Waters and Stanton Video Channel" for this excellent introduction to random wire antennas. The SWR values you show are right where they should be. Here are some of Paul's observations: "This is my new design of the small 9:1 UnUn for portable QRP Random Wire Antenna. The antenna can be Oct 19, 2019 · Reviewing the PackTenna Mini antenna with a POTA activation. Consider becoming a Patron @ https://www. Works well with both internal transceiver and external antenna tuners. The idea is that some lengths just won’t work well on one or more bands. See this link for more info. Dec 7, 2022. Figure 2 Typical 9:1 voltage unun and long wire antenna configuration with an earth May 14, 2022 · 1. Jan 25, 2020 · Modified RANDOM WIRE ANTENNA with 9:1 UnUn (part 2) Random Wire Antenna with 9:1 UnUn. com/store/p1/PackTenna_Mini_Random_Wire_Antenna_%289%3B1_UNUN%29. How to Build a 9:1 UnUn for Ham Radio Antenna. Dec 10, 2018 · 4. So a 9:1, or greater, ratio of balun may reduce the impedance sufficiently to help your tuner get a match and help avoid a voltage flash-over in your tuner. , all go for a toss if the EFHW antenna wire is deployed with random and haphazard orientations. The place where a 9:1 or 49:1 transformer balun matches the off center impedance isn’t at the very end, but close to the end. With a little planning, this useful antenna accessory can be made in only a few hours. Since playing with pedestrian mobile and discovering that I can use my K6ARK 9:1 unun to drive my 55" collapsible back pack antenna directly without a loading coil, the "random wire" antenna has come back to my attention. Yes, we can use this antenna also as a multiband dipole, when harmonic resonant frequencies allowes us to work also on some other bands. 8-61 MHz), 500 watt PEP rating, and a connection for a counterpoise or ground if desired. LDG Electronics RU-9:1 Unun. It requires some sort of ground connection to work. An unun is like a balun, but while a balun goes from balanced line to an unbalanced antenna, the unun has both sides unbalanced. Of particular importance is the design, construction, and testing of a 9:1 Unun, which is an integral part of this antenna system. I think the matchbox is terrific. Which helps in improving the signal transfer. Here are some of John's comments: Simple and inexpensive to build the 9:1 end fed long wire antenna is a good antenna for both portable and home use. The idea is to bring the impedance if a "random wire" down to a value your tuner can handle. First, this is not, technically, a BALUN (BALanced-UNbalanced line transformer), but a UNUN (UNbalanced-UNbalanced line transformer)The picture I've added shows a standard circuit diagram for a 9:1 UNUN. Generally the 9:1 has far more loss as the transformer/core takes on heat to make the non-resonant antenna be of any use across wide bandwidths and are Jul 9, 2020 · Baluns and ununs are essential in RF signal chains for many applications. This 1:9 UnUn is built around an FT240-43 ferrite ring core. Here are some general comments from Gil: Building a 9:1 UNUN for a random-wire multi-band end-fed antenna using an FT-140-43 toroid instead of the usual T106-2. May 1, 2021 · The antenna's radiation efficiency, lobe patterns, gain, etc. A properly designed random wire combined with a UnUn balun and a wide-range "tuner" can often get you on the air when nothing else will. 49:1 or other high ratio transformers are for resonant "cut to frequency" antennas like the traditional zepp/fuchs antenna. Thanks to "The Smokin Ape" for this in depth analysis of the theory and practical applications of end-fed random wire antennas. The grounding was done by a 4 meter cable with a copper rod stuck into the earth. The other end connects to the random-wire connector on a suitable antenna tuner. The EFHW with the same feed had a noise floor of S8! My attic 20m dipole is normally S4-S5 on the same band (tested at the same time). ) and can be used on multiple bands with an antenna tuner. com/k8mrdradiostuffFollow m Jan 22, 2020 · This is post 2122 in a continuing series of simple ham radio antennas. A very simple antenna to make, deploy and use is an end fed wire antenna. One end of the wire attaches to a tree, pole or other support, preferably at a high point. Thanks to Tinker John (W5CYF) for this "nice one-evening project" that will prove useful for both home station use and for field operations. Check out TheSmokinApe Merch Shop: https://shop. Jan 24, 2020 · Modified RANDOM WIRE ANTENNA with 9:1 UnUn (part 2) Random Wire Antenna with 9:1 UnUn. A wire antenna kit, with a coil of wire, strain insulators and a balun. g. Post 2121. Multi-Band HF Fan Dipole Antenna Construction; Ham Radio - The Doublet antenna, QSOs and observat Ham Radio - The Doublet. prcguy said: On the 9:1 types the coax can be part of the antenna, so I would put it away from the entry point of the house to catch any RFI riding on the coax from things in the house but far enough from the 9:1 transformer to be useful for reception. An old but good multi-ba I own both the Packtenna Random Wire Antenna and the 20/40 meter EFHW linked dipole antenna. The antenna element works the same as any other antenna. ujm-49-1 . I currently have a 36-ft random-wire antenna going into a home-brew 9:1 un-un, with no counterpoise but 50ft of coax into my home station. An old but good multi-ba Jan 24, 2019 · A Communicator Reprise: February 2014. An end fed, 1/2 wavelength antenna will have a relatively high impedance of 5k ohms or more. Post 2112. Instead of using the coax as the 'other half' of the antenna, I prefer to use a counterpoise array. The most common end-fed antennas are the half-wave and random Workable: Attach counterpoise stud on unun to a good ground rod at the feed point of the antenna. The current one doesn't cover 80m, and I'd like to see if I could add that band. For do-it-yourself antenna builders, 9:1 impedance transformer information is HERE Feb 7, 2020 · 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. Jack Clarke, VE3EED - SK. All you need for a random wire Recommended wire lengths and Configuration Notes for Unun models 4932, 4935, 9130, 9132 & 9135 The following tables show the recommended lengths to use for the antenna wire based on the bands you wish to cover. With my IC-703 it tuned 80 through 6 all well below 1. To operate on any HF band you need a wide range tuner like the internal Apr 26, 2023 · An end-fed antenna is a type of wire antenna where the feed point is located at one end of the antenna wire, rather than at its center (as in a dipole antenna). Model 4134 - 4:1 Unun 1. Noise from Longwire Antennas. Probably the most familiar is the end fed half wave antenna (EFHW) But random length or non-resonant end fed antennas are also popular and effective, especially for portable use. For do-it-yourself antenna builders, 9:1 impedance transformer information is HERE Jul 5, 2023 · We recently installed a long wire antenna for our club, it's approximately 87m length and slightly sloping with a 9:1 un:un and no earth. 4:1 impedance ratio is 2:1 turns ratio. patreon. In part two of his Random Wire antenna project, Paul (OM0ET) finishes the 9:1 balun and proceeds to test the complete antenna system on the air. Nov 10, 2022 · This video discusses End Fed antennas and particularly End Fed Random Wire antennas for ham radio. jpeg. common mode noise ingress. Utilizes stacked cores to deliver efficient broadband performance and high power rating across all HF frequencies. Here are some of Paul's observations: "This is the following video of the Home made Random Wire Antenna with 9:1 UnUn. sv dt bf os he hx dn uh ud hh