Below is a photo of my QTH. page 1 of 2 hf antennas g5rv dipoles efhw antennas r2010071 eantenna efhw4 end feed dipole 70 mhz. This is less important if you have a resonant half wave or multiple but you don't have that. 1:1 Current Balun by N5ESE Here's another handy little Altoids QRP project. On the two wires between the 1:9 balun and the Hi-Z port I have a large type 43 ferrite. Windom - Similar to the OCFD. Type : 49:1 Unun. 5MHz to 50MHz. Choke baluns are often combined with impedance transformers to provide both. Focusing only on current is a serious oversight that can result in defective system design. Displaying 1-3 of 3 Aug 8th 2017, 17:16: KI7LFD Joined: Mar 13th 2017, 22:46 Total Topics: 0 Total Posts: 0 : I'm currently considering a EFHW-8010 End fed antenna for use with a new FT-1200 transceiver. Introduction The EFHW monoband matching unit (inspired by AA5TB) allows for a half wavelength of wire to be connected, giving a 50 Ohm impedance match to the transmitter (without a ground plane or ATU) at the frequency of operation. An unbalanced transmission line (coaxial cable) connected to a dipole antenna. 261 Pittman Road, Landrum, SC 29356. 0 0 1 212 1171 Com One LTD 9 2 1381 14. Building a 4:1 balun. EFHW-A, box for 50/70 MHz EFHW antenna. The full isolation I mentioned above is only part of why I think this. 18 or smaller wire. BALUN UNUN 1:49 - 49:1 For End Fed Half-Wave (EFHW) antenna 500W - $39. The balun that I chose (Model #1171t) is a current balun which effectively operates in series with the signal path (unlike a more common "voltage" balun which typically resembles an autotransformer as in the case of a typical 4:1 balun) and is essentially a common-mode choke that isolates one side of the balun from the other by virtue of the. Construction of the 9:1 balun/unun: I used an old plastic box and a type 75 toroid core. This includes the “line isolators” (for example, the DX Engineering Maxi-Core 20 50-ohm 1:1 Feedline Choke) and all types of bead balun. The feed-point was about 4' above ground, sitting outside on a window "ledge". I use stealth end fed in my attic. Off Center Fed Dipole - Feed point is 20-33% from one end. Rg58 as counterpoise. It will take full legal limit (UK) of 400 Watts RF power easily and is used to convert a 200ohm impedance to the 50ohm required by most transceivers of today. So, a "multi-band end-fed half-wave" antenna is actually a bit of a misnomer A "half-wavelength" radiator has a high impedance ( = high voltage, low current) at the feedpoint. 5MHz - 50MHzTurns ratio: 1:7Impedance. 5 MHz but our amateur radio 17 M band allocation is a shade higher in frequency at 18. For what an EFHW will cost you to make you should give it a try, we cant all be wrong. For SWL-ing a smaller core can be used along with No. Type : 49:1 Unun. The RadioWavz DX80 Proline (with High Efficiency balun) Windom is ideal for those of you who do not use a tower and beam. Requiring a unun to feed a long wire antenna ideally without a tuner a 9:1 voltage unun design using a T200-2 Toroid core was selected. The balun belongs to a class of devices known as “transmission line transformers”. Thanks for your interest in my HWEF article. The purpose of this group is to explore the use of an end fed half wave antenna. I heard and read balun designs were good. A quick look at the QB-300 RF amplifier Available from many surplus sellers (e. 261 Pittman Road, Landrum, SC 29356. " order_by="sortorder" order_direction="ASC" returns="included" maximum_entity_count="500″] QRPGuys Portable No Tune Half Wave Antenna - $20 Your PayPal receipt is your confirmation that we have received your order. 14 solid copper wire. The efficiency is 98 percent. 100MHz to 27GHz. Par EndFedz® Antennas are low-power End Fed Half Wave (EFHW) antennas with the match box coax connection at the end of the wire, for convenient and quick stealth portable operations. page 1 of 2 hf antennas g5rv dipoles efhw antennas r2010071 eantenna efhw4 end feed dipole 70 mhz. Unlike many END FED antennas on the market, this one does not require the Antenna Tuner to operate. v Abstract Two-way communications using 3 to 30 MHz, high-frequency (HF) radio, also known as shortwave radio, provides worldwide coverage with no infrastructure required between stations. Capacitor 100pF 40KV. 24 strand wire, 40ft coax, Works Great on 20-10-6. Power Handling(CW/SSB) : 400W /800W and 1KWW of peak power. / NO TUNER needed / wire not included/one End Insulator included Product Description MEF-330-1K Multi Band End Fed Half Wave Antenna Transformer This is an End-Fed. 2m 6m 10m 15m 20m 40m 43 foot 70cm 80m AHVD Aluminum APRS Baluns battery BigIR collinear Diamond dipole DX-Eng. The new antenna is the EFHW-4010 manufactured by MyAntennas. The RadioWavz DX80 Proline (with High Efficiency balun) Windom is ideal for those of you who do not use a tower and beam. The center is 20 feet long and the two outer ends are 6-1/4 feet each. noise rejection, which is one of the balun's attributes - and should be exploited as such. 160M Is a Tough Band • Propagation quite variable, signals often not very strong, heavy QRN during the summer –Mostly a nightime band, varies a lot through the night –During the winter, 800 miles or. 20 meter Vertical w/ Balun Author: Frederick R. Antenna wire in red. 80m,40m,20m,10m It's also ideal for those who want a high performance antenna with world class DX coverage. Had two 20m SSB QSOs running 20w. A choke type balun should be used with this antenna to eliminate or reduce the undesirable parallel feedline currents. Then use an insulator to mount the balun. Adding capacitors does not affect loss very much below 17 m, but increases loss. Otherwise deal is final. If you plan on stringing up a dipole you use 2 equal lengths of wire with the Balun in the middle. A Balun is used to "balance" unbalanced systems - i. 5 MHz (5xf0) is 17. A simple 20 meter vertical with matching balun. Withstand power 100W PEP. End Fed Antennas One of the most popular antennas today is the end fed antenna due to it ease of installation, portability and stealth in various installations. The lamp zip cord used as a balanced feed line has about 105 ohms impedance. Apr 18, 2017 - End Fed Half Wave Antennas. I've been generally happy with the performance of my 5 band trapped EFHW antenna and have used it on many SOTA activations. EFHW portable antenna for SOTA activations. 30 Watts QRP, 40-10 Meters, 66 feet. EFHW-8010 Multi-Band End Fed Half Wave Antenna-NO TUNER NEEDED! This is an End-Fed Half-Wave (EFHW*) antenna for 80/40/30/20/17/15/12 and 10m bands. I have occasionally used a 58 ft wire with a 13ft counterpoise directly on the KX2 but still prefer the EFHW. The classic sloper antenna is a top-fed 1/4 wave vertical antenna sloping down and away from a tower. 2020 popular Hf Balun trends in Consumer Electronics, Replacement Parts & Accessories, Wireless Module, Radio with Hf Balun and Hf Balun. Wiring Diagram Electric Car Antenna Posted on July 21, 2011 by admin 1986 420sel hirschmann antenna bench test peachparts mercedes k6jrf auto page power wiring diagram the car will not start toyota aftermarket power antenna wiring diagram mercedes electric 1991 power antenna gif. IMPORTANT: Most OEM balun manufacturers will sell you a simple single core 1:1 or 4:1 ( OCFD, Loops, etc. Reading about EFHW antennas, it strikes me that the W3EDP is really just a particular case of the EFHW: it's parallel tuned, and the antenna length is selected to give good performance on the traditional ham bands, although mine works well on the WARC bands, too. 068 MHz current curve is shown in lighter grey on the graph, a shade to the left of the 17. 30 Watts QRP, 40-10 Meters, 66 feet. An End Fed Half Wave Length Antenna is a variation of the much more common half wave length dipoleantenna. An Unun is used to match an unbalanced line to another unbalanced line. Mast heights and spacing can be easily adjusted in the model. I wanted to see if 20m was open to CA. 5 to 1 or less SWR on ham bands 80 to 10 meters- no antenna tuner needed. It has a constant impedance transformation ratio of 64:1 from 3. Facebook Group - EFHW Antennas Steve Ellington N4LQ started up a group on Facebook called End Fed Half Wave Antennas. Standing wave <1. Despre Random Long Wire (un articol foarte bun) Despre Antena Tuner. In that case, expected efficiency (meaning PowerOut/PowerIn) of the transformer was less than 65% at 3. The fifth harmonic of 3. MFJ-1778 G5RV Wire Antenna 80-10 Meters - Authorized Dealer. I replaced the OCF dipole with a single end-fed antenna for 40, 20, 15 and 10 meters. Longwire Antenna: The suggested balun is a 4:1 ratio current choke Tuner Balun. Quando un'antenna è lunga mezza lunghezza d'onda, presenta una distribuzione di corrente che è al massimo al centro e una distribuzione di tensione è al massimo in corrispondenza delle estremità (fig. Baluns are usually used to feed dipole antennas with 50-ohm coax and to transpose from ladder line feeding a multi-band antenna to the unbalanced input of an antenna tuner. The End Fed antenna is very popular especially for field work. Get the best deal for End Fed Antenna from the largest online selection at eBay. Whether you`re QRPbackpack, vacationing, emcomm station, or an antenna neighbors will never see, MFJs got an EFHW for you: MFJ-1982LP, $49. 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. The main category is Baluns manufacturers that is about Balun vendors. Capacitor 100pF 40KV. PackTenna makes ultralight, portable HF amateur radio antenna systems and accessories. A balun is a 3-port network that converts a signal on an unbalanced transmission line to properly deliver or receive power from a balanced transmission line, which is often needed for coaxial cables and dipole antennas. Today l put up my 29ft one as a sloper with a 17 ft counterpoise. Multiband End Fed Half Wave EFHW Antenna these transformers are often referred to as "ununs" as opposed to the more familiar balun that matches a balanced to unbalanced line. Unlike many END FED antennas on the market, this one does not require the Antenna Tuner to operate. End Fed Half Wave Antennas Facebook Group – EFHW Antennas Steve Ellington N4LQ started up a group on Facebook called End Fed Half Wave Antennas. Wiring Diagram Electric Car Antenna Posted on July 21, 2011 by admin 1986 420sel hirschmann antenna bench test peachparts mercedes k6jrf auto page power wiring diagram the car will not start toyota aftermarket power antenna wiring diagram mercedes electric 1991 power antenna gif. My balun was hotter then blazes. They are only used to block common-mode current. Antenna wire in red. The Hertz antenna is an antenna with an electrical length of a half wavelength at its resonant frequency. The Elecraft BL-2 is a switchable 1:1 / 4:1 balun that is capable of handling 250 Watts (but only when a matched load is attached) as well as small enough to be used in portable operations but again, it really needs to be matched with a non reactive load. Basically a loaded antenna uses a coil of wire in the center or top to create the rest of the wavelength. Is the matchbox itself part of the antenna system, part of the transmitter, or an independent device on its own?. Extended Double Zepp Antenna - Duration: 8:09. You will need to supply the wire and coaxial cable by yourself since the shipping cost is high. Is that a common experience?" A guy responded with a question something like, "Why does everyone use a 9:1 balun and coax with their random wire antennas. 100MHz to 27GHz. Mast heights and spacing can be easily adjusted in the model. Whether you use a Balun or a UnUn, depends on how you are feeding it. 18 or smaller wire. Type : 49:1 Unun. power: 300 W PEP. The RadioWavz DX80 Proline (with High Efficiency balun) Windom is ideal for those of you who do not use a tower and beam. This attenuates the AM band pretty well I think. Although not necessary, a 1:1 isolation/choke balun (models, 1110, 1113, 1115 etc. Had two 20m SSB QSOs running 20w. " order_by="sortorder" order_direction="ASC" returns="included" maximum_entity_count="500″] QRPGuys Portable No Tune Half Wave Antenna - $20 Your PayPal receipt is your confirmation that we have received your order. W4KDA's Original Build 160m long 529' of 18 AWG stranded wire L = 1004 / f 20 - 50' off the ground Simple coax to wire break out (no BALUN) "Tuner" at the radio This is the way most hams install and use their loops Worked "okay" at best. 1 Why use an end fed antenna? Years ago the end fed antenna was the most popular HF antenna type used by radio amateurs. One end goes straight into the rig, often with no feedline, and the other end in the air attached to something as high as you can find. 068 MHz current curve is shown in lighter grey on the graph, a shade to the left of the 17. 6MHz of a common design using a FT82-43 ferrite core with a 3t primary. There are also many options are available to purchase. 1 offer from $199. I used sililar box as yours. I started experimenting with HWEF antennas way back in…. A choke type balun should be used with this antenna to eliminate or reduce the undesirable parallel feedline currents. Despre Random Long Wire (un articol foarte bun) Despre Antena Tuner. 20 meter Vertical w/ Balun Author: Frederick R. Browse our daily deals for even more savings! Free shipping on many items!. Both antennas need a 1:1 choke-balun at the BALanced twinlead to UNbalanced coax junction to minimize coax feedline radiation and RF-in-the-shack. John was asking why I didn't just borrow the balun from that to test on the inverted L. Sometimes however, the centre feed is not ideal, for example when you want to use it as a vertical. Don, VE3MNE, made me a home brewed, double core, 49:1 balun for use with an End Fed Half Wave Antenna or EFHW. Remember, the 9:1 balun is doing a conversion of impedance from about 450-700 ohms down to 50 ohms. BALUN UNUN 1:49 - 49:1 For End Fed Half-Wave (EFHW) antenna 1KW - $51. If winding inductive reactance becomes marginal at lower frequencies, the balun's ability to eliminate antenna currents is reduced, but (for the 1:1. HFedz Antennas Fanpage. Connect the earth side of the balun to an earth stake (I have a screw in ground stake that supports the fishing pole and have put a bolt and wing nut on it). The End Fed antenna is very popular especially for field work. His basic design starting point was the half size G5RV, to which he added inductors on each leg. In addition to those, should I also put a choke balun on. 100MHz to 27GHz. I heard and read balun designs were good. Many of the hams in my club already use them, right down to QRP power levels, with great success. As an example, consider a coaxial cable connected to a half-wave dipole antenna shown in Figure 1. EFHW antenna's are really a good choice if you are looking to deal with a specific deploying situation or want a low visual impact antenna. I put up a mono-band end-fed half-wave (EFHW) antenna - 66' in length - for use on 40 meters several months ago. Just assume that Antenna Tuner means the same thing as Antenna Matchbox. Array Broadside and end fire patterns, Balun Module-II (12 Antenna Engineering Handbook - Firebase Antenna Engineering Handbook By Richard C Johnson Antenna Engineering Handbook By Richard C Johnson Newly revised and updated, this best-selling reference provides the essential principles, methods, and data needed to solve the engineering problems. In Equipment. > Try a 64:1 balun. This review of NI4L’s 7 band OCF dipole was prompted by my needing a quick deploy multiband antenna for both field day, and for RVing. The WireMan, Inc. If you aren't sure why your antenna needs a BALUN, you can read more about them in our Tech Info page above, or in the Blog entry by Danny Horvat, N4EXA / E73M. I lose MW and LW, but I'm in the middle of the country and don't get any LW anyway. >> >> >> Everything is present EXCEPT the little matching network that couples the >> EFHW to the radio. As you can see I fit a full sized 80m EFHW (End Fed half wave) antenna measured at 130ft. Capacitor 100pF 40KV. End-fed, half-wave antennas (EFHWs) are a half-wavelength long and are resonant antennas on the band of interest. Multiband End-fed 80-10m antenna. Update: Full size 132ft EFHW For one month I replaced the 66ft wire and loading coil and replaced it with a full 132ft of wire, connected to the FT240-43 balun. Baluns are usually used to feed dipole antennas with 50-ohm coax and to transpose from ladder line feeding a multi-band antenna to the unbalanced input of an antenna tuner. Mention to anyone you are using an EFHW will prompt a discussion about the pros and cons of the EFHW versus the center fed 1/2 wave dipole. This was a little bit of a compromise as the last 20ft of the antenna had to run down a fence to fit it into the garden. Dispelling myth that grabbing coax. The antenna is 33-feet tall and uses stranded 20-ga insulated wire in three sections. Be prepared and able to communicate in case of emergency with the largest selection at eBay. The same holds for the sheath current choke. EFHW Dipole. This link is listed in our web site directory since Sunday Jan 19 2003, and till today "International Technology Antennas" has been followed for a total of 5012 times. 5MHz to 50MHz. RITUAL SEX. 0 out of 5 stars 11. By design, ununs are wound is such a manner that they provide little or no RF choking. The primary reason for using a balun at the feed point of a dipole antenna is to prevent RF currents from flowing on the outside of the shield of the coax feeding the antenna. Adding capacitors does not affect loss very much below 17 m, but increases loss. 5MHz - 50MHz Turns ratio: 1:8 (2. Tested EFHW Matchbox components - Fail! Leave a comment Posted by rjbono on July 23, 2016. Antenna wire in red. Unlike many END FED antennas on the market, this one does not require the Antenna Tuner to operate. I have the balun fed 25'+ from the shack with an RG-214 feed line, which lays on the ground. Also see other baluns and ununs: 1:1 Choking balun Choking balun for lower HF and MF bands. End feeding offers mechanical advantages, heavy bits (coax and balun) can remain at the bottom of the antenna. Steve Nichols G0KYA Contents 1. Choke baluns are often combined with impedance transformers to provide both. What they do and how they do it. Model 49131 - 49:1 80-10m EFHW - Up to 1kW Balun Designs now offers an excellent alternative. Nice write-ups and comments. In effect the W3EDP is an EFHW for 80m (126 ft top, 17 ft counterpoise, just under. We sell all types of hf wire antennas for ham radio, if you are looking for quality hf base station antennas at a great price then look no further, we stock hf wire antennas, and more, from all the top antenna manufacturers, includes cushcraft antennas, diamond antennas, radioworks antennas, comet antennas, watson antennas and more. 5MHz - 50MHzTurns ratio: 1:7Impedance. 5% shorter than a dipole. 30 Watts QRP, 80-10 Meters, 132 feet. (14 ~ 54MHz) FT140-43 Ferrite Toroid Core. Apr 18, 2017 - End Fed Half Wave Antennas. By design, ununs are wound is such a manner that they provide little or no RF choking. The end fed half wave is clearly a favorite. I am planning to setup the 30 ft military pole with the Buddipole for the first time tomorrow if the wind cooperates. 160M Is a Tough Band • Propagation quite variable, signals often not very strong, heavy QRN during the summer –Mostly a nightime band, varies a lot through the night –During the winter, 800 miles or. 56 results for end fed antenna Save end fed antenna to get e-mail alerts and updates on your eBay Feed. I found that using a short ground wire to an aluminum tent peg in the ground immediately beneath the 49:1 balun helps the SWR. _____ Un'antenna End Fed a semionda intera, è una variazione del molto più comune dipolo semionda intera. " However, I am somewhat confused about placement of the 'balun'. 2 turns primary and 14 turns secondary. The max OD for wire is 3mm, but it. I built the antenna using two 10m fishing poles spaced 5m apart. EFHW-A, box for 50/70 MHz EFHW antenna. By design, ununs are wound is such a manner that they provide little or no RF choking. PackTenna makes ultralight, portable HF amateur radio antenna systems and accessories. The sloper's feed point is anchored high above ground near the top of the tower on which sits a grounded HF yagi beam antenna. The 4:1 BALUN is connected directly to the IC-703 antenna socket. De balun hing op ongeveer 11m boven de grond, en de uiteindes van de draden op ongeveer 4m. Joined: Feb 23, 2008 Messages: 2,024. Elecraft BL2 BALUN Specifications & Operating Manual BALUNS. Thanks for your interest in my HWEF article. End Fed Antennas One of the most popular antennas today is the end fed antenna due to it ease of installation, portability and stealth in various installations. A special case of this, is the End-Fed Half-Wave (EFHW) antenna. 5MHz to 50MHz. The 1:1 balun is 18 turns of RG8x on two 2. May 13, 2015 No comments. I'm going to have to bite the bullet and reroute the EFHW. 0, 09/01/18. But I don't know. Construction of the 9:1 balun/unun: I used an old plastic box and a type 75 toroid core. efhw Pukul 11. This was my first sprint, and it was a lot of fun! WA2FBN - Lots of good sigs on 20 and 40. A so-called random wire antenna is an end fed antenna. The second purpose is to prevent electrical noise and other unwanted interfering signals which may be carried on the outer of the coax from being conducted into the receive path. > > With that antenna and counterpoise length, dispense with the balun. Look at the bottom of the page for the complete parts. Specifications: Size 36 x 15 mm (1. PackTenna makes ultralight, portable HF amateur radio antenna systems and accessories. 0 Normal 0 21 false false false EN-GB JA X-NONE 49:1 Unun This is a unun ( unbalanced to unbalanced ) transmission line transformer designed to match 2450Ω to 50Ω. Takes up less space. Browse our daily deals for even more savings! Free shipping on many items!. Power Handling(CW/SSB) : 200W /400W and 500W of peak power. Note first, the terms "voltage balun" and "current balun" are as defined on this site. 95 special order : mfj1984mp. 1:1 Choking balun low band VHF Choking balun for lower band VHF. Quick View. This antenna is formed by arranging the long wire in a V-shaped pattern. 261 Pittman Road, Landrum, SC 29356. The sloper's feed point is anchored high above ground near the top of the tower on which sits a grounded HF yagi beam antenna. Thanks for your Comments Mark! I am glad you felt inspired to make one of these - ununs and baluns used to be a dark magic thing for me that you would sacrifice a goat and things happened until I had a go at actually making one. Recommended wire lengths and Installation Notes for Unun models 4932, 4935, 9130, 9132 & 9135 Table shows typical SWR relative to installed wire length. Power Handling(CW/SSB) : 400W /800W and 1KWW of peak power. 30 Watts QRP, 80-10 Meters, 132 feet. MFJ-1982MP. May 13, 2015 No comments. This fixed the problem. It is also the same as that used on the M0CVO HW range of antennas. This antenna can be angled anywhere in a range from 0° as a Half-Wave Vertical Dipole, to 90° as a flat-top Horizontal Dipole. This is less important if you have a resonant half wave or multiple but you don't have that. Super Antenna MP1LXMAX Deluxe Tripod 80m-10m HF +2m VHF Portable Antenna with Go Bags. 2m 6m 10m 15m 20m 40m 43 foot 70cm 80m AHVD Aluminum APRS Baluns battery BigIR collinear Diamond dipole DX-Eng. The antenna we used was a portable multi-band end-fed half wave (EFHW) 40-10m with a 49:1 Unun. On some bands you might only need a 4:1 Balun/UnUn. Find many great new & used options and get the best deals for 2020 Balun 1:49 - 49:1 For 5-35MHZ End Fed Half-Wave EFHW antenna 100W HAM at the best online prices at eBay! Free shipping for many products!. If you aren't sure why your antenna needs a BALUN, you can read more about them in our Tech Info page above, or in the Blog entry by Danny Horvat, N4EXA / E73M. EFHW antenna's are really a good choice if you are looking to deal with a specific deploying situation or want a low visual impact antenna. Unlike many END FED antennas on the market, this one does not require the Antenna Tuner to operate. The 4:1 BALUN is connected directly to the IC-703 antenna socket. Standing wave <1. KC2SST [E] 7 points · 2 months ago. For SWL-ing a smaller core can be used along with No. My Icom IC-703 internal ATU is capable of matching the impedances shown below. Every year our club’s Field Day operation puts a six meter […]. La realizzazione di questo balun è molto semplice e copre la gamma di frequenze da 1,8 a 60 Mhz. 100MHz to 27GHz. The 4:1 BALUN is connected directly to the IC-703 antenna socket. 5 m) is used to match 50 ohm coax to the balun and antenna. 100 Watt, with solid tensile stools. 0 0 1 212 1171 Com One LTD 9 2 1381 14. Is this equivalent to the same thing or should I have a 1:1 at the. BALUN UNUN 1:49 - 49:1 For End Fed Half-Wave (EFHW) antenna 500W - $29. After a while, the SWR started climbing, so I retuned. com in 8 categories. at least 25 feet of coax. Buyer Protection. I have a couple of end-fed wire antennas I bought that came with matching baluns. MEF-330-1K Multiband EFHW Antenna Transformer, Covers 8 Bands / 80-10m / 1kW-max. The NEC file of the Terminated Inverted U antenna can be downloaded here. If "RF in the shack" is a problem, install a 1:1 choke balun near where the coax enters your shack. This video shows how I made my 49:1 transformer for my End Fed Half Wave antenna. RITUAL SEX. > > On Mon, Jan 8, 2018 at 5:59 PM, Rich Arland <[hidden email]> wrote: > >> I have one of the original PAR end fed half wave antennas prior to LNR >> taking over production and sales. But one station said I had RF on my audio. Power Handling(CW/SSB) : 400W /800W and 1KWW of peak power. We continue our antenna offerings with this single band, 80m-10m end fed half wave wire antenna. I lose MW and LW, but I'm in the middle of the country and don't get any LW anyway. 64:1 Unun This is a unun ( unbalanced to unbalanced ) transmission line transformer designed to match 3200Ω to 50Ω. By design, ununs are wound is such a manner that they provide little or no RF choking. View details & Buy. ; Fast Setup and takedown. The feedpoint impedance of a Dipole in free space is close to 75Ω. 5 average on other bands including the WARC bands. I sourced the parts kit from Ebay and just had to assemble it as before. Many of the hams in my club already use them, right down to QRP power levels, with great success. 1 Why use an end fed antenna? Years ago the end fed antenna was the most popular HF antenna type used by radio amateurs. Wire Antennas for the Beginner Every ham knows how to make and install wire antennas. I am planning to setup the 30 ft military pole with the Buddipole for the first time tomorrow if the wind cooperates. 160M Is a Tough Band • Propagation quite variable, signals often not very strong, heavy QRN during the summer –Mostly a nightime band, varies a lot through the night –During the winter, 800 miles or. A special case of this, is the End-Fed Half-Wave (EFHW) antenna. > Brian, > > If your end fed antenna is actually a halfwave (which is what EFHW > means), the answer is no. The center is 20 feet long and the two outer ends are 6-1/4 feet each. This is a great antenna as it has 1. Choke baluns are often combined with impedance transformers to provide both. Homebrew 4:1 BALUN 30 MHz wide VSWR scan of the BALUN into a 200 ohm resistor Rear view Circuit diagram. This is ready to test as soon as tomorrow. Generally, they are not usable on bands for which they are not a half wavelength long. With a little care, the end fed half wave, EFHW antenna is an ideal choice for many ham radio, and even. I do run a tuner though. He was running an IC-7200 and 100W. You don't need skin effect to explain why common-mode and differential-mode are distinct either: that's true because any linear system can be described as. Other antennas include the zepp, the half square and the Double Bazooka antenna. Most of the construction videos or sites teach how to make the 99:1 xfrmrs from ferrite cores the size of truck tires laced with cable used on Edison's 500KV high tension lines -- presumably so that if VOA needs to erect one, they have a ready watch-n-learn resource. The yagi plays the role of a ground plane, while the tower plays the double role of reflector and grounding "rod". COMTEK Jerry Sevick W2FMI Series Current Baluns were inspired by the writing of Jerry Sevick, as published in his book "Understanding, Building, and Using Baluns and Ununs" also available from DX Engineering Find COMTEK Jerry Sevick W2FMI Series Current Baluns COM-BAL-41130T and get Free Standard Shipping on orders over $99 at DX Engineering!. Multiband EFHW. VERY BAD! Most matchboxes cannot match this low impedance. Using the EFHW for 20m at GB0CMS 3. You never quite know when the band will open and where it will take you. > > The solution for portable work is to use a length that is not a > halfwave - 58 feet is known to work well for 40 thru 10 meters when > used with a 13 foot counterpoise. By design, ununs are wound is such a manner that they provide little or no RF choking. I will write an updated version but until then, even though the article originates from october 2012 and is kind of outdated, I think it's still a good starting point. I'm trying to decide what to do about a common-mode choke for this antenna. Your feed line is essentially the counterpoise, so a separate one is not necessary if you want to keep weight. 10 METER DIPOLE 1:1 1500w SSB/PEP 200w CW (16' 9"). In a pinch, i in shot 170 ft of wire 85ft into a tree with balun at 12 ft and 100ft. Basically a loaded antenna uses a coil of wire in the center or top to create the rest of the wavelength. A quick look at the QB-300 RF amplifier Available from many surplus sellers (e. 18 or smaller wire. Last year on Field Day I was able to use an OCF dipole for the first time, and I enjoyed the quick bandswitching it allowed, so I thought I'd try and find a good OCF dipole for use while in the field. 49:1 UnunThis is a unun ( unbalanced to unbalanced ) transmission line transformer designed to match 2450Ω to 50Ω. 1 XBalun 1:49 - 49:1 For 5-35MHZ End Fed antenna 100W HAM. Longwire Antenna: The suggested balun is a 4:1 ratio current choke Tuner Balun. 30 Watts QRP, 80-10 Meters, 132 feet. Unhappy with the results, he then played around with the overall length and added a balun at the feedpoint. SWR is 1:1 on the half wave frequencies, and matchable with the KX2 internal tuner on the multiples. An ugly balun and short line to the transmitter will allow operation on 40 meters. The balun that I chose (Model #1171t) is a current balun which effectively operates in series with the signal path (unlike a more common "voltage" balun which typically resembles an autotransformer as in the case of a typical 4:1 balun) and is essentially a common-mode choke that isolates one side of the balun from the other by virtue of the. Northwest Antennas Shortwave End Fed Wire Antenna w/Balun, 45' x 30", UHF Connector by ER-RADIO. " order_by="sortorder" order_direction="ASC" returns="included" maximum_entity_count="500″] QRPGuys Portable No Tune Half Wave Antenna - $20 Your PayPal receipt is your confirmation that we have received your order. Ham Radio HF Dipole Antenna suppliers category is a curation of 40 web resources on , Antenna Tensioner Vari-Ten, RippleTech Electronics, Sandpiper Aerial Technology LTD. 5MHz to 50MHz. Type : 64:1 Unun. The center is 20 feet long and the two outer ends are 6-1/4 feet each. MFJ-1984LP, $39. Be prepared and able to communicate in case of emergency with the largest selection at eBay. The end fed half wave is clearly a favorite. 0054m, this captures the magnetic path geometry of the binocular core. 30 Watts QRP, 40-10 Meters, 66 feet. Many of the hams in my club already use them, right down to QRP power levels, with great success. Whether you`re QRPbackpack, vacationing, emcomm station, or an antenna neighbors will never see, MFJs got an EFHW for you: MFJ-1982LP, $49. Customers who viewed this item also viewed End Fed EFHW-8010-1K 80M-10M wire antenna 5. It is available with a 1KW or 2KW rated balun. Ham radio antennas. The balun belongs to a class of devices known as “transmission line transformers”. Requiring a balun to feed a balanced feed line from an un-balanced T-Match tuner, a 1:4 Guanella Current balun design using two L15 ferrite toroid cores was selected among other balun types. These single-band and multi-band antennas can be mounted horizontally, vertically, or as a sloper. The antenna cannot be an actual 1/4 wave length on any ham band. 3 watts, and the ferrite bead balun will dissipate about 13. Para el balun necesitar un rojo T-TOROID 200/2 AMIDON , envuelva las bobinas 9 TRIFILARI en alambre de cobre esmaltado y cruzó al dibujo, por favor cablear todo en una caja sellada, en el que el cable de derivación va a salir la boquilla única SO239 y el casquillo de la antena de cable. EFHW-4010-1K Multi-Band End Fed Half Wave Antenna. The RadioWavz DX80 Proline (with High Efficiency balun) Windom is ideal for those of you who do not use a tower and beam. Known as the Magic Band, the six meter band can be mysterious, unpredictable, and downright fun. If the transformer box is installed high above the ground, there is no need to route the ground wire from the box, instead just ground the coaxial cable at the entrance to your home or at the station. Due to the nature of wavelength and impedance at various frequencies there is a magic wire length to use for this type of balun. KC2SST [E] 7 points · 2 months ago. End feeding offers mechanical advantages, heavy bits (coax and balun) can remain at the bottom of the antenna. View details & Buy. 00WIB tanggal 10 saya akhiri QRP DXpedition ini mengingat perolehan QSO sudah tidak begitu signifikan lagi. Unlike many END FED antennas on the market, this one does not require the Antenna Tuner to operate. A BALUN is needed to isolate the antenna common mode current from the station. Quick View. Then use an insulator to mount the balun. Your feed line is essentially the counterpoise, so a separate one is not necessary if you want to keep weight. Steve Nichols G0KYA Contents 1. 95 out of stock : mfj1984hp : mfj mfj1984hp: 40-10 meter 800 watt efhw antenna $77. It cleared up when I switched to the EFHW. 10 METER DIPOLE 1:1 1500w SSB/PEP 200w CW (16' 9"). EFHW antenna's are really a good choice if you are looking to deal with a specific deploying situation or want a low visual impact antenna. With a handy fixing plate for the toroid, so no longer necessary for gluing. I lose MW and LW, but I'm in the middle of the country and don't get any LW anyway. The center is 20 feet long and the two outer ends are 6-1/4 feet each. The are also two wideband units for end fed half wave (EFHW) antennas matching half wave wire antenna for 160 to 30m or 80m to 10m. BALUN UNUN 1:49 - 49:1 For End Fed Half-Wave (EFHW) antenna 500W - $39. 95 special order : mfj1984mp. With a little care, the end fed half wave, EFHW antenna is an ideal choice for many ham radio, and even. Tested EFHW Matchbox components - Fail! Leave a comment Posted by rjbono on July 23, 2016. The RadioWavz DX80 Proline (with High Efficiency balun) Windom is ideal for those of you who do not use a tower and beam. 5MHz to 50MHz. Building a 4:1 balun. I am assuming that your referring the the MyAntennas version of the EFHW-8010? I can't help you with the opening of the sealed balun box. A so-called random wire antenna is an end fed antenna. I built 9:1 balun wigh t240 teroid. page 1 of 2 hf antennas g5rv dipoles efhw antennas r2010071 eantenna efhw4 end feed dipole 70 mhz. > > The solution for portable work is to use a length that is not a > halfwave - 58 feet is known to work well for 40 thru 10 meters when > used with a 13 foot counterpoise. No the inverted L feed point is at ground zero. So I put up an EFHW Dipole antenna for my HF transceiver. 5 average on other bands including the WARC bands. A tip passed on via my reading of other’s findings. The Balun Requirement section describes how to construct a choke balun for this antenna. I have one EFHW 130 foot antenna that is a horizontal antenna. Generally, they are not usable on bands for which they are not a half wavelength long. The antenna is from MyAntennas. Complete antenna and end lines on a kite winder. Choke baluns are often combined with impedance transformers to provide both. at least 25 feet of coax. an Effective Working Balun: EFHW Antenna ---Building The Transformer #105 Balun Part 3: How to Build an Effective Working 4:1 Balun for 800 Watt HF Power: EFHW End Fed Half Wave Antenna Higher Power Using 52 mix Ferrite #131 Balun Part 4: How to Build an Effective working 9:1 Balun for 800W input power: Winding a Transformer for End Fed Half. Connect your SWR meter/ analyser to the balun and see where it resonates. If I had known about this, I would have got the EFHW-4010-2K, which is only $20 more and is rated for up to 2kW-ICAS. The next generation in Design and manufacturing. These are multi-band, center-fed dipole antenna capable of 1,500 watts. Multiband EFHW. End Fed Half Wave Antenna Coupler (EFHW) 1:1 Voltage Balun for HF wire dipoles; 9:1 Magnetic Longwire Balun / Unun; Simple CW Touch Keyer Circuits; Capacitive CW Touch Key Circuits; 2N6084 144MHz FM Power Amplifier; G3XBM 472kHz Transverter; Rig to Soundcard Interface; PIC controlled 500w 'Modified Sine Wave' Inverter. 5KW PEP) Application. End-fed horizontal wire, an EFHW, offers the perfect solution for a wide range of ham activities. 14 KB Binaural Basics. As you can see, the SWR is better than 2:1 for parts of each of the bands of interest using a fixed EFHW matching unit (described here). via EvilBay) - and (usually) for a reasonable price - is the QB-300 RF amplifier. It cleared up when I switched to the EFHW. Our Current Type BALUNs are expertly designed and measured for maximum resistive choking impedance over your desired bandwidth. 30 Watts QRP, 40-10 Meters, 66 feet. But if you or someone reading this wants to have the same antenna with a box that can be opened and cleaned/repaired and save some money along the way. 95 out of stock : mfj1984hp : mfj mfj1984hp: 40-10 meter 800 watt efhw antenna $77. This link is listed in our web site directory since Sunday Jan 19 2003, and till today "International Technology Antennas" has been followed for a total of 5012 times. The classic sloper antenna is a top-fed 1/4 wave vertical antenna sloping down and away from a tower. 2019-03-21a I spent most of the afternoon playing with my end fed half wave antenna. Balun 1:49 - 49:1 For 5-35MHZ End Fed Half-Wave (EFHW) antenna 100W HAM 0. Capacitor 100pF 40KV. 5MHz) therefore also resonant on second, third and fourth harmonics etc. 0 0 1 212 1171 Com One LTD 9 2 1381 14. The feed-point was about 4' above ground, sitting outside on a window "ledge". The Sloper Antenna Explained The classic sloper antenna is a top-fed 1/4 wave vertical antenna sloping down and away from a tower. More on the EFHW Antenna 3 Comments Posted by rjbono on July 19, 2016 Steve Yates – AA5TB has written a good piece on the care and feeding of the End Fed Half Wave antenna. Failure to use a choke balun may result in RFI, RF feedback, or other symptoms of RF "in the shack". 5 MHz (5xf0) is 17. An unbalanced transmission line (coaxial cable) connected to a dipole antenna. Focusing only on current is a serious oversight that can result in defective system design. The Balun Requirement section describes how to construct a choke balun for this antenna. Plus they can work well. These baluns see half the load voltage, so at 1500 watts to a 50 ohm load, the power dissipated in the coaxial baluns will be less than 1. An end fed half wave antenna is one of a specific length depending on the frequency that it…. In effect the W3EDP is an EFHW for 80m (126 ft top, 17 ft counterpoise, just under. PackTennas are light weight, compact, portable HF antenna systems ideal for operating on the trail, at the campsite, on Field Day, SOTA activation, air travel, or HOA restricted locations. 30 Watts QRP, 80-10 Meters, 132 feet. ; End-Fed Horizontal Wires (EFHW) cover multiple bands with-out traps. In addition to those, should I also put a choke balun on. Ham Radio Wire Antenna Calculator. wire and are rated up to 4kW Find Palstar B4K 4:1 Current Baluns B4K-4-1 and get Free Standard Shipping on orders over $99 at DX Engineering!. Baluns and UnUns. com and I believe it to Wed 15th Apr 2020, 16:33. Whether you use a Balun or a UnUn, depends on how you are feeding it. Palstar B4K 4:1 Current Baluns are designed for indoor use in Hi-Z antenna applications for center-fed wire antennas with open wire and twin lead transmission lines. 160M Is a Tough Band • Propagation quite variable, signals often not very strong, heavy QRN during the summer –Mostly a nightime band, varies a lot through the night –During the winter, 800 miles or. The sloper's feed point is anchored high above ground near the top of the tower on which sits a grounded HF yagi beam antenna. As you can see, the SWR is better than 2:1 for parts of each of the bands of interest using a fixed EFHW matching unit (described here). 5MHz to 50MHz. EFHW-A, box for 50/70 MHz EFHW antenna. Balun 1:49 - 49:1 For 5-35MHZ End Fed Half-Wave (EFHW) antenna 100W HAM 0. efhw Pukul 11. Easy to Install and Use KM5M on 23rd Apr 2014 The NI4L end-fed 40-6m dipole antenna is just about perfect for portable operation. Browse our daily deals for even more savings! Free shipping on many items!. My grab and go SOTA station now consists of: - MTR3B (or the MTR5B) - Palm Radio Pico Paddle - 460mAh LiPo battery - Headphones (earbuds) - 10m travel pole (SOTABeams), I have long Velcro straps attached to wrap around fence posts. Using a 4:1 balun in this case would transform the impedance even lower, down to 5 Ohms (or less). RITUAL SEX. In effect the W3EDP is an EFHW for 80m (126 ft top, 17 ft counterpoise, just under the traditional 132 ft. Get the best deal for End Fed Antenna from the largest online selection at eBay. noise rejection, which is one of the balun's attributes - and should be exploited as such. Whereas the resonant 1/4 wavelength wires tend to have much lower feed impedance (450 Ohms) and only requires a 9:1 Balun/UnUn. Moravian Falls, NC 28654 United States of America (828) 738-6445. End-fed horizontal wire, an EFHW, offers the perfect solution for a wide range of ham activities. 14 Responses to "Comparing receive signals with and without 1:1 balun. NO5V/1 is the EFHW tuned for 20m and NO5V/2 is the same wire as the EFHW but run as a non-resonant end fed with a 9:1 matchbox and about 30 feet of coax as counterpoise. SWR is 1:1 on the half wave frequencies, and matchable with the KX2 internal tuner on the multiples. 100 Watt, with solid tensile stools, all stainless steel. It cleared up when I switched to the EFHW. 30 Watts QRP, 40-10 Meters, 66 feet. So I put up an EFHW Dipole antenna for my HF transceiver. John was asking why I didn't just borrow the balun from that to test on the inverted L. This item 2019 Balun 1:49-49:1 for 5-35MHZ End Fed Half-Wave EFHW Antenna 100W HAM MFJ-1778 G5RV Wire Antenna 80-10 Meters - Authorized Dealer Super Antenna MP1DXTR80 HF SuperWhip Tripod All Band 80m MP1 Antenna with Clamp Mount and Go Bag ham Radio Amateur. 30 Watts QRP, 80-10 Meters, 132 feet. 5:1 to 1:1 on 40m. > > On Mon, Jan 8, 2018 at 5:59 PM, Rich Arland <[hidden email]> wrote: > >> I have one of the original PAR end fed half wave antennas prior to LNR >> taking over production and sales. I am putting up a homebrew resonant end-fed dipole for operating on 10/20/40m. $225 - SGC SG-239 Smartuner. My Icom IC-703 internal ATU is capable of matching the impedances shown below. The second purpose is to prevent electrical noise and other unwanted interfering signals which may be carried on the outer of the coax from being conducted into the receive path. EFHW Antenna and 49:1 UnUn. ) at the transmitter end of feedline will stop RF from entering your equipment and reduce receiver noise caused by common mode currents. COM The Mini Wire Antenna can be used with D4D DSB Transceiver for FT8, HT-1A CW Transceiver and other QRP power level transceivers. Steve Nichols G0KYA Contents 1. 1 offer from $199. I am using a EFHW 40 mtr ant that has a "49-1 ratio transformer" on the end of the coax that connects to a 66ft ant wire. Sometimes however, the centre feed is not ideal, for example when you want to use it as a vertical. Random Wire Antenna Lengths. The crossover counts as a turn. As always, thanks Chris. 30 Watts QRP, 80-10 Meters, 132 feet. Takes up less space. But I don't know. 5 average on other bands including the WARC bands. FULL HF Coverage, no tuner needed on most frequencies. View details & Buy. I use an EFHW built for 40m with a jumper to shorten it for 30 meters. Now,follow UHF High Banc!, UHF 800190O MHz tnmked public safety and publicservice systems;ust as if conventional two-way communications were used. The EFHW-4010 is rated at 1kW ICAS, but your mileage may vary, especially depending on the particulars of your installation (like any metal objects in the near field of the antenna that can detune it). A single choke balun cannot change impedances between the input and output. Welcome to the new PackTenna web site. For SWL-ing a smaller core can be used along with No. May 13, 2020 - Explore v51rjwill's board "ham radio" on Pinterest. An overview and where it all started 2. A choke type balun should be used with this antenna to eliminate or reduce the undesirable parallel feedline currents. End Fed antenna applications. Here are some answers. Balun and Core Selection: (mostly receiving) Contains information on core selection for transformers and baluns (it isn't a balum) Balun, sleeve baluns: How a sleeve balun works and what is important. Unlike many END FED antennas on the market, this one does not require the Antenna Tuner to operate. He was running an IC-7200 and 100W. Portrayed below is a complete and self-contained NEC model of one popular form of the end-fed half-wave dipole antenna. You can use a choke balun, but it must be used at the rig end of the coax feed, NOT next to the UNUN or you will have no counterpoise and the EFHW will not work. ; No long counterpoise, radials or feedline required. Is a Balun needed or helpful - EF Antenna. Don’t forget the choke on the coax feedline about 10ft back from the feedpoint. As the late spring and summer months heat up, six meters comes alive. The crossover counts as a turn. This was my first sprint, and it was a lot of fun! WA2FBN - Lots of good sigs on 20 and 40. noise rejection, which is one of the balun's attributes - and should be exploited as such. Therefore you can use simpler antenna mast, say fibreglass rod instead of tower. This antenna was built with the same quality workmanship and attention to detail as our military, government and commercial wire antenna products. (EFHW) (Click "SHOW MORE" below to see the Amazon links)You will learn what you need to order and where you. I heard and read balun designs were good. Next up was WA5OBV - Phil in Oklahoma. Quando un'antenna è lunga mezza lunghezza d'onda, presenta una distribuzione di corrente che è al massimo al centro e una distribuzione di tensione è al massimo in corrispondenza delle estremità (fig. I'm going to have to bite the bullet and reroute the EFHW. Connect the earth side of the balun to an earth stake (I have a screw in ground stake that supports the fishing pole and have put a bolt and wing nut on it). The feed-point was about 4' above ground, sitting outside on a window "ledge". , il diametro interno di 35 mm. Don, VE3MNE, made me a home brewed, double core, 49:1 balun for use with an End Fed Half Wave Antenna or EFHW. ; Easy Storage/transport. Basically a loaded antenna uses a coil of wire in the center or top to create the rest of the wavelength. wire and are rated up to 4kW Find Palstar B4K 4:1 Current Baluns B4K-4-1 and get Free Standard Shipping on orders over $99 at DX Engineering!. Construction of the 9:1 balun/unun: I used an old plastic box and a type 75 toroid core. Built with the same craftsmanship as all our other units, this new model will allow you to either replace your current matching unit or construct a new higher power end fed half wave antenna. Voltage baluns have transfer losses while current baluns don't other than the resistance of the wire. W4KDA's Original Build 160m long 529' of 18 AWG stranded wire L = 1004 / f 20 - 50' off the ground Simple coax to wire break out (no BALUN) "Tuner" at the radio This is the way most hams install and use their loops Worked "okay" at best. Here is a photo of a transformer and 100 pF capacitor: I easily got SWR from 1. Using'Current'Chokes' Transmi^er'current'travels'on'center'conductor'and'inside'of'the'shield'of'coNaxial'cable'feed' line'–'shield'current'feeds'antenna'leg'and. 0 Normal 0 21 false false false EN-GB JA X-NONE 49:1 Unun This is a unun ( unbalanced to unbalanced ) transmission line transformer designed to match 2450Ω to 50Ω. The balun used is a 6/1 but there are some interesting facts and tests on various cores. Failure to use a choke balun may result in RFI, RF feedback, or other symptoms of RF "in the shack". I run a simple EFHW balun that was like $36 on eBay. Highest SWR is 2 to 1 on 80 meters with 1. As you can see I fit a full sized 80m EFHW (End Fed half wave) antenna measured at 130ft. Don't install a choke close to the matchbox feed point if you are relying on the coax as the counterpoise; this will prevent the coax shield from functioning as a counterpoise. So I put up an EFHW Dipole antenna for my HF transceiver. The balun that I chose (Model #1171t) is a current balun which effectively operates in series with the signal path (unlike a more common "voltage" balun which typically resembles an autotransformer as in the case of a typical 4:1 balun) and is essentially a common-mode choke that isolates one side of the balun from the other by virtue of the. The efficiency is 98 percent. The current horizontal EFHW is up about 35 feet in a tree. Other antennas include the zepp, the half square and the Double Bazooka antenna. Some references suggest #2 material whilie others #6 material to wind 9:1 balun. Introduction The EFHW monoband matching unit (inspired by AA5TB) allows for a half wavelength of wire to be connected, giving a 50 Ohm impedance match to the transmitter (without a ground plane or ATU) at the frequency of operation. COM The Mini Wire Antenna can be used with D4D DSB Transceiver for FT8, HT-1A CW Transceiver and other QRP power level transceivers. On some bands you might only need a 4:1 Balun/UnUn. Northwest Antennas Shortwave End Fed Wire Antenna w/Balun, 45' x 30", UHF Connector by ER-RADIO. 14 solid copper wire. EFHW-8010P- 200W Portable or Stationary Multi-Band End Fed Half Wave Antenna This is a 200W version of popular EFHW-8010 End-Fed Half-Wave (EFHW*) antenna for 80/40/30/20/17/15/12 and 10m bands. 0 Normal 0 21 false false false EN-GB JA X-NONE 49:1 Unun This is a unun ( unbalanced to unbalanced ) transmission line transformer designed to match 2450Ω to 50Ω. Takes up less space. They feature nylon insulators and a large 3. All products are quality checked. As I indicated above the FT-140-43 toroid is great for a balun but because of its high permeability resulted in over. ed una permeabilità di 40. An End Fed Half Wave Length Antenna is a variation of the much more common half wave length dipoleantenna. 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. An ugly balun and short line to the transmitter will allow operation on 40 meters. This antenna can be angled anywhere in a range from 0° as a Half-Wave Vertical Dipole, to 90° as a flat-top Horizontal Dipole. The shield side of the cable is usually grounded. Using that in a calculator to iteratively find the value of ΣA/l that gives Xs=35Ω at 7MHz, we obtain ΣA/l=0. For SWL-ing a smaller core can be used along with No. EFHW-4010-1K Multi-Band End Fed Half Wave Antenna. Par EndFedz® Antennas are low-power End Fed Half Wave (EFHW) antennas with the match box coax connection at the end of the wire, for convenient and quick stealth portable operations. The few matchboxes that can actually match it, generally have high internal losses when doing so. If the transformer box is installed high above the ground, there is no need to route the ground wire from the box, instead just ground the coaxial cable at the entrance to your home or at the station. If Yin of the loaded transformer is 0. Actually, looking at how this works, I'm about 95% sure this is a balun, not an unun. Both antennas need a 1:1 choke-balun at the BALanced twinlead to UNbalanced coax junction to minimize coax feedline radiation and RF-in-the-shack. This is a unun ( unbalanced to unbalanced ) transmission line transformer designed to match 2450Ω to 50Ω.