EN. 156. Fig. The 4-band Fritzel model FD4 is a special version of a Windom antenna. Ham radio call database for everyoneThe feedpoint of the 3-band antenna is not in the center, but more like a windom system: Off Center Feed (OCF). Fritzel used the shown dimensions of 13. To: n4ujw@hamuniverse. FD4's are by wide ranges. EMEA. English Deutsch Français Español Português Italiano Român Nederlands Latina Dansk Svenska Norsk Magyar Bahasa Indonesia Türkçe Suomi Latvian Lithuanian česk. Mohu Leaf: $35. About The FD4 Windom antenna The resource is currently listed in dxzone. Balun C. Yeasun FT 857 D. 8-m and 27. A shorter version FD3 for 40-10m operation is also developed. Dipol - FD3 - FD4 (1/1) TA4AU: Hi All. America. This garbage disposer offers a simple, efficient, and economical way to dispose of food waste in restaurants, hotels, or hospitals serving up to 1000 meals per day, or cafeterias, commissaries, or schools. hello, 13,5m; 27,5M and a 1:6 balun. Furthermore, none of these designs offered 30 m. Success, after several years, I finally manage to get out of the block of flats and into a family home, and I would like to replace CB with something more interesting, e. Add a comment. Ona je dugačka pola valne duljune L. Le petit plan de masse est trés pratique "radians courts" :gain de place au sol par rapport aux radians d'une verticale 1/4 d'onde. The renowned “FD4” antenna was not an exception; Have a look at its VSWR specification on pages 13 and 14 of this brochure. Belakangan, karena di feed di titik yang melèncèng dari tengah bentangan antenna (OFF-center) seperti yang kemudian umum dilakukan, maka rancangan ante nna macam ini lantas disebut sebagai off-center fed atau OCF antenna. And they seem quite slack . The second gate is directly connected to terminal 13 by removing R210 (10 k). University merilis tulisan tentang cara menala half -wave antenna dengan pengumpanan lewat single wire ini. 0: Using (but not overusing) DX Spotting and Making Manual Logging Easier. Simply push the waste into. 7-m in the 1960s. The FD4 Windom. 202 - Two Elements Phased Delta Loop for 40m. Most Popular. If the installation site permits, a dipole antenna in a vertical "Vee" configuration has radiation patterns suitable for NVIS applications -- and can have useful low-angle radiation, as well. FD4S-B288S00JDB2. Hi all, I bought the Mini1300 from China and Software says Version1. A while back a ham in the Far East set up a Visa account system where you sent him a donation via credit card and he used that to mail back a hard card qsl. $99. 2023-10-25. The G5RV has a reasonable SWR on 80, 40, 20, 15, and 12 meters. . 2004-02-19. Topic: Dipol - FD3 - FD4 (Read 3108 times) 0 Members and 1 Guest are viewing this topic. De tråde som Verner//OZ9XU anbefaler dig at montere, giver glimrende resultater. It is an off centre fed dipole, with 10 feet of vertical radiator. The Fritzel FD4 antenna becomes more popular in Europe and N. 13-20 describes a modified VS1AA OCFD with a 4:1 balun connected to a coaxial feeder. Added: 07/18/2019. So here at my home there is also room for improvement. Antenna tuner for 10 to 80 m, but also suitable for 50 and 70 MHz bands. It comes complete with a 1:6 balun with SO-239 connector. 3 MHz. 7-m in the. Z tego też względu w. power 1 kW, approx. This split allows the OCFD to be operated as a 4 band antenna as the SWR on the 40m band is less than 3. 1971 - Dr. It is a half-wave long on the lowest frequency, and is fed from a coax cable through a transformer. The graphic below shows its performance on the 40/80/160m bands for the conditions shown there. 6O6X. VAT, plus shipping €63. It is a half-wave long on the lowest frequency, and is fed from a coax cable through a transformer inserted in the wire at one-third from one end. 13-20 describes a modified VS1AA OCFD with a 4:1 balun connected to a coaxial feeder. Because of its bigger. I was amazed what DX I worked from this antenna and QRP andUniversity merilis tulisan tentang cara menala half -wave antenna dengan pengumpanan lewat single wire ini. It was designed to cover 80, 40, 20 15, and 10 meters. It turns out that 100 feet of line is within about 10% of the idea length to match the antenna to 50 ohms on all amateur bands. Jobbat is el tudtam volna képzelni. At present some Czech amateurs call it "PA0FRI" antenna. More recently, as described in an Appendix to a detailed discussion of Windom-type antennas 'The off-centre-fed dipole revisited: a broad-band, multiband antenna' by Dr John Belrose, VE2CV, and Peter Bouliane, VE3KLO (OST,secure the ends, the 4-Band antennas need at least 60 feet of ground space from end-to-end. Elsewhere in Africa, David, VE7VR is active as A25VR from Botswana until 3 June. A shorter version FD3 for 40-10m operation is also developed. The antenna was clipped to the RTL-SDR V3 antenna base without the telescoping whip – alligator clipped to the threaded mast. HamSphere 4. The 4-band Fritzel model FD4 is a special version of a Windom antenna. 8-m and 27. Download the model according to the specified sizing parameters in either 3D or 2D format. Antenna Windom Links → . About How to construct a multi-band dipole using speaker wire The resource is currently listed in dxzone. com Home Mapsite Add Link. The Fritzel FD4 antenna becomes more popular in Europe and N. The. com. Documentation. One would argue that the stations worked would simply mail some funds to these DXpeditions to offset the lost income included with QSL requests. English Deutsch Français Español Português Italiano Român Nederlands Latina Dansk Svenska Norsk Magyar Bahasa Indonesia Türkçe Suomi Latvian Lithuanian česk. Please select a product. . 8-m and 27. The Hobart FD4/150-2 garbage disposer offers a simple, efficient and economical way to dispose of food waste in restaurants, hotels, or hospitals, serving up to 500 meals per day, cafeterias, commissaries, or schools serving up to 1000 meals per day, or vegetable/salad prep areas of restaurants serving up to 2000 meals per day. 8-m and 27. Also: Someone asked if there was any usefulness of FT8. The system has an impedance of 70 - 100 Ohm and for connection. The GPA-30 trap was used because water often seeps in with an R6000 trap and the construction is not as robust as that of Fritzel antennas. One would argue that the stations worked would simply mail some funds to these DXpeditions to offset the lost income included with QSL requests. DX Code Of Conduct. be. Add To Cart. See physical description below. Coax extension2020-06-21 : Tried 6 m with my IC-7300 and a FD4 antenna. In stock, shipped in 1 to 2 days. It is a half-wave long on the lowest frequency, and is fed from a coax cable through a transformer inserted in the wire at one-third from one end. 52m long ( TT, October 1972 and ART): Fig 5. De antenne wordt op eenderde van zijn The second leg is the "counterpoise". Hi all, I bought the Mini1300 from China and Software says Version1. The sectional mast is a low-loss coaxial feed line for unequal length crossed dipole radiating elements which are attached to guy ropes for mast support. Equipment will be similar to September 2011 WAE SSB Contest work, with the Kenwood TS570D and Windon FD4 antenna. 800 Watt FD4 multi-band antenna with 1:4 super balun Project for a multi-band antenna for the 80, 40, 20, 17, 12, 10 and 6 meter bands, including a 1:4 impedance transformer and. 2350 103. Watch on. This link is listed in our web site directory since Friday Mar 10 2017, and till today "How to construct a multi-band dipole using speaker wire" has been. While most of the antennas were made by "name" manufacturers, the Gesobyte and the Btfdreem were chosen specifically. 45 m 13. This link is listed in our web site directory since Sunday May 6 2007, and till today "K7MEM - Inverted V Antenna Design" has been followed for a total of 4381 times. vy 73 de Ron DG1HVW F4ATM Laurent schrieb: Hello, i need all lenghts of wires and balun type ( 1/6 or 1/4 )to make a Windom antenna 10m to 80m. Main "coax lifter kites 2. Antenna Windom Links → . The antenna can be employed on 80, 40, 20 and 10m with considerable, though acceptable levels of VSWR. New. There is an amateur antenna out there consisting of an 80-meter dipole (I mean one that is a half wave at 80 meters, not one physically 80 meters long) fed with about 100 feet of 450 ohm ladder line. OK2SWD. Homemade Carolina Windom antenna. HamSphere 4. TrademarkElite is the U. The 7-band antennas need at least 120 feet of ground space end-to-end. Antena ta zostałą opracowana na użytek wojska przez United States Navy pod koniec lat 40-tych. VAT, plus shipping €63. WINDOM. By 1937 the Windom was described “as multi-band antenna that can be employed on harmonically related 160, 80, 40, 20 and 10m bands with acceptable levels of VSWR”. DESIGN. By 1937 the Windom was described “as multi-band antenna that can be employed on harmonically related 160, 80, 40, 20 and 10m bands with acceptable levels of VSWR”. . Republic of Germany 4, 04450 Federal Republic of Germany (26. Zmierzyłem się w końcu z demonizowaną przez wszystkich anteną T2FD, ale zacznijmy od początku. I myself am working with a simple FD4 Antenna. Fritzel FD4 OCF Dipole The Frizel FD4 Windom is an OCF (Off Centre Fed) antenna that has been around for a long time. Most Popular. S. #1 Trademark Search and Registration Service :: TUNNEL VOICE FD4 is a trademark and brand of Tunnel Radio of America, Inc. 5. It had the same dimensions as the VS1AA multiband Windom antenna, but fitted with a 300Ω balun in its feedpoint and fed over coax. 80,40,20,17,12,10m Seperate parts for balun, isolator, wires. The dual dipole wires do the job of providing guying support for the mast. This is a pity, because most hams would put up a wire antenna especially for the lower bands where beam antennas are more difficult to erect. ( 3 ) Estimated Ship Date: Monday 11/20/2023. Installation de l'antenne filaire FD4 de chez Fritzel sur un pylône de 6 mètres en V inversé la rendant omnidirectionnelle. Most antenna tuners work best into moderate to high impedances, rather than low impedances. Belakangan, karena di feed di titik yang melèncèng dari tengah bentangan antenna (OFF-center) seperti yang kemudian umum dilakukan, maka rancangan ante nna macam ini lantas disebut sebagai off-center fed atau OCF antenna. Military AS-2259/GR There are a number of different NVIS antenna plans on the internet that can be adopted to amateur radio use. The Standing Wave Ratio (SWR) is the parameter that is easiest for most hams to measure, as meters are very common, both built into many newer radios or as a shack accessory. The newer baluns are suited for more power, output 700 W/CW and 1400 W/SSB. However, two problems remained: The next section explains why traditional OCF dipoles have these inherent lim-itations. 70cm directional antennas with 16 -. 1750 114. See physical description below. 0, but I wonder how to send WSPR or FT8. If the installation site permits, a dipole antenna in a vertical "Vee" configuration has radiation patterns suitable for NVIS applications -- and can have useful low-angle radiation, as well. (35' on 75M. University merilis tulisan tentang cara menala half -wave antenna dengan pengumpanan lewat single wire ini. Topic: Dipol - FD3 - FD4 (Read 3275 times) 0 Members and 1 Guest are viewing this topic. Fritz Spillner, DJ2KY, in 1971[1]. Visit my web site: OCF FD4 (FD3) WINDOM ANTENNA. Tu je smješten balun 1:6. receivers, city env. balun, incl. And the length of the legs must match. I know this is an old thread - but Hofi in Germany still manufactures the antenna. 206 - X-Ray Monoband Antenna Gain=6. 5m and 2. Very close to the 300 Ohm impedance of a Windom antenna such as the system used in Fritzel's FD3 and FD4 antennas. I improved my setup with a FT920, 3 el Monobander for 10m and made Packet Radio in 1997. hofi de) . 7-m in the. This link is listed in our web site directory since Sunday Jul 29 2007, and till today "Windom Antenna with 4:1 balun" has been followed for a total of 8010 times. This antenna talks! The logs don’t lie. 8-m and 27. The dipoles are cut for roughly 6. pc is a toughbook cf19 wx is quit good,strong winds, 9 xxxx & yyyy are the names of the two participants. I still young so I thinks this is normal, didn't we all start small. And the length of the legs must match. 1971 - Dr. . Searching for Fritzel Windom (Fritzel in business?) 4. The Carolina Windom is described in (Straw 2007) who attributes it to Edgar Lambert (WA4LVB), Joe Wright (W4UEB), and Jim Wilkie (WY4R) who published a variation on the ‘original' Windom. In addition, an R6000 has two separate traps for 12 and 17 m, while the 10 and 15 m traps of a. is the designer and trade mark holder, and primary source for Bury-Flex Tm low loss coax cable. 3 dB gain, incl. English Deutsch Français Español Português Italiano Român Nederlands Latina Dansk Svenska Norsk Magyar Bahasa Indonesia Türkçe Suomi Latvian Lithuanian česk. QSL via DJ6SI. 7. Fritz Spillner1, DJ2KY, in 1971. 204 - Low Radiation Angle Full-Wave Loop Antenna for 80m. MHz 4. One would argue that the stations worked would simply mail some funds to these DXpeditions to offset the lost income included with QSL requests. The performance characteristics are quite outstanding. ifos for FD4 or other antenna. The windom antenna can also be hung as a. See you again, friends . Belakangan, karena di feed di titik yang melèncèng dari tengah bentangan antenna (OFF-center) seperti yang kemudian umum dilakukan, maka rancangan ante nna macam ini lantas disebut sebagai off-center fed atau OCF antenna. . 1971 300 Ω 41. 200 - Inverted-V Beam Antenna for 30m. 75 MHz. $44. Bonnes bandes passantes en général ,elle est trés efficace en DX et surpasse toute mes autres antennes FB13-FD4-W3EDP de 1 à 2 points S. I0JXX 50 MHz Yagi antennas. The 4-band Fritzel model FD4 is a special version of a Windom antenna. The asymmetrical dipole antenna developed and described by Windom (W8GZ) in 1929 has been used by many amateurs for many years as the FD4. 0 Extras: Using the Editor to Customize Your Transceiver. The FD4 antenna for 20/40/80 had a lot of interference on 80 that we could not trace to a source in the building. Add a comment. Antenna parts category is a curation of 58 web resources on , Sandpiper Aerial Technology LTD, HexKit. VAT, plus shipping €201. The dimensions were the same as the multi-band Windom antenna, but fitted with a 200Ω (4:1) balun at its feed point and fed with 50 ohm coax at lower heights above the ground. For the PAL8010OCF, the impedance is very well behaved in a limited, easy to match range throughout the 1-54 MHz range and, in fact, that antenna also works very. Fritzel FD4 antenna, described by the late Dr. The FD4 (FD3) Windom Antenna The 4-band Fritzel model FD4 is a special version of a Windom antenna. The half-size version of the FD4 is known as the FD3 (40,20,10m) and is the subject of this article. It covers 7 bands, 10-12-15-17-20-40-80m. It is a convenient indicator of how well the transmitter load matches the output impedance for which the transmitter was designed, and it often is the first indicator of a. 11ax) Adapter with 2 External. This link is listed in our web site directory since Thursday Jun 23 2016, and till today " HF Linked Dipole Antenna Calculator " has been followed for a total of 1468. Picture courtesy Holger, OX3HI. . The store where radio amateurs and specialists buy Everything from one source Fast delivery Excellent support See for yourself!The G5RV has a reasonable SWR on 80, 40, 20, 15, and 12 meters. Fritz Spillner, DJ2KY, in "Die FD4-Windom-Antenne," QRV, Stuttgart, 25, December 1971, pp. 7 Mllz arc available if the high fre- quency is directly coupled out. Systems FCC-4 half-wave dipole antenna, also know as the reference dipole antenna, is the simplest form of an antenna. Fritz Spillner, DJ2KY, in 1971. power 1 kW, approx. The diagram gives no guidance on key implementation details such as height, and the nature of the common mode. DK2CF IC-7400 100Watt Dipole and Delta loop DK4WF FT-890 FD4 Windom 17m high DL7JOM K3 750W LPDA DL7ULM IC706 Indoor-dipole 2 x 11 metres FD4 de chez Fritzel - Antenne. A. VSWR performance is worse only on 17m and slightly on 40m. com The 4-band Fritzel model FD4 is a special version of a Windom antenna. 6m is also dead, useable only for experiments and local contacts here. The dimensions were the same as the multi-band Windom antenna, but fitted with a 200Ω (4:1) balun at its feed point and fed with 50 ohm coax at lower heights above the ground. 6m directional antennas with 5, 6 or 7 elements, 1 kW. It also works fine on all bands above 40m with a tuner, and even below 40m on 60m, and 80m, although the coax losses will be higher. A shorter version FD3 for 40-10m operation is also developed. 5m. America. Furthermore, none of these designs offered 30 m. But for a "real" FD4 the RF transformer should have 4:1 or as some say 2:1 when the height above ground is. 73, Ray K1XV . I m stuck It is possible to get into a location where you can moveUniversity merilis tulisan tentang cara menala half -wave antenna dengan pengumpanan lewat single wire ini. , Corvallis, OR . EN. This has also been the case in Germany. if you want to rate The FD4 (FD3) Windom Antenna use this special. 5 mtr RG-58 panjang sebarang ke TX atau ATU 27 mtr Balun 1:6 Di Eropa, rancangan Multiband Windom dengan coax sebagai feeder line yang menonjol adalah rancangan yang dikembangkan oleh Dr. The main category is Dipole antenna that is about Dipole antennas plans. See It. Do long wires work better than say a standard half wave or quarter wave antenna?Ask an Elmer discusses this very interesting question by one of our viewers. The following plot shows the measured SWR of an FD4 antenna from 3 MHz to 30 MHz with about 20 m of RG58U feeder line. 1x Radioddity RA-FD4 8. 826 (3. So far received 3. Antenna, 160 Meter Single Band Wire Dipole, 1500 W, SO-239, Kit. • Radioddity's limited warranty applies to all BRAND NEW items sold by radioddity. It cover. NVIS Antenna Strategy • Portable and field antennas will be less efficient due to space, height and setup time • “Command post” or “Net Control” antenna should be as efficient as possible • Gains of up to 6 dB (i. Svar til #1: Velkommen tilbage til denne fantastiske hobby. It is my back-up HF antenna, and one that can be used on 40 meter round table rag chews where a beam may not be ideal. Coax D. Though works on the other bands with an ATU. More recently, as described in an Appendix to a detailed discussion of Windom-type antennas 'The off-centre-fed dipole revisited: a broad-band, multiband antenna' by Dr John Belrose, VE2CV, and Peter Bouliane, VE3KLO (OST,What became perhaps the most popular multiband Windom design of all, was the German-made Fritzel FD4 antenna, described by the late Dr. The antenna was designed for military use from 2 to 10 MHz (some references say 2 to 30 MHz). , DJ2KY modified the VS1AA antenna design by replacing the single feed wire with balun and a coax feeder. Dat is op de laagste frequentie een draad van een halve golflengte. Both of these proved to FD4 (80/40/20/10 m) The 4-band Fritzel model FD4 is a special version of a Windom antenna. If you do the math, it emits about 1. rig is a codan 2110v 25w fd4 antenna 15ft above ground yyyy, ur station is amazing! do u qsl js8. So I checked the frequency and had to adjust it (27MHz calibration) But still. Ashok Use your search engine to find 'FD3 antenna' and 'FD4 antenna' - I see many hits. The FD4 antenna for 20/40/80 had a lot of interference on 80 that we could not trace to a source in the building. This is a pity, because most hams would put up a wire antenna especially for the lower bands where beam antennas are more difficult to erect. 80,40,20,17,12,10m Seperate parts for balun, isolator, wires. By the end of the 70's interest in the Windom. -V 80. Ultra Vizion HD Digital TV Antenna: $44. FD4 antena ima problem sa napajanjem. RUMORS OF THIS ANTENNAS DEATH ARE GREATLY EXAGGERATED Time Owned: 0 to 3 months. 1x Radioddity RA-FD4 8. 00 €. Hy Power Antenna Company - US amateur radio antenna manufacturer. Flag at 50m point E. I myself am working with a simple FD4 Antenna. The half-size version is known as the FD3 40-20-10m antenna. 00. Displaying 1 to 8 (of 8 products) Result Pages: 1. This is still the most popular shortwave antenna, whether in amateur radio, for the military, public services or commercial users. However the waveform didn't look very good to me. One of the most versatile and inexpensive wire Antenna for 10-80 meter Band. It covers 7 bands, 10-12-15-17-20. What became perhaps the most popular multiband Windom design of all, was the German-made Fritzel FD4 antenna, described by the late Dr. 8-m and 27. I just checked my EU1KY Analyzer on the spectrum analyzer. (Note the FD3 will also be around 66 feet total length for operating on 7 MHz and. Also, a power amplifier, L4B, is on the way to Baghdad. The FD4 (FD3) Windom Antenna. The Windom - Off Centre Fed Half Wave Dipole Antenna. The half-size version is known as the FD3 40-20-10m antenna. De ingetekende 13. COM in Germany because the exchange rate for euros was low. 2 29. Napajanje je na L/3 odnosno 2L/3. 47 kB, 1280x1024 -. antenna. I also have a 10 Metre Dipole in the loft. Fritz Spillner, DJ2KY, in "Die FD4-Windom-Antenne," QRV, Stuttgart, 25, December 1971, pp. America. But it was over water, the villa pool hi. The dipoles are cut for roughly 6. Délután 4-re már állt az FD4 antenna és az azt tartó pecabot. FD4 antenna, fent mérve a kábelhossz beszámításával. The main category is Dipole antenna that is about Dipole antennas plans. This is a pity, because most hams would put up a wire antenna especially for the lower bands where beam antennas are more difficult to erect. 25 10. a Windom (FD4) antenna I liked to satisfy my wish in having a beam antenna usable in the the upper bands. The performance characteristics are quite outstanding. that's not what I'm trying to explain. 154. Vertical antennas made of steel wire, monoband or multiband, with balun and radials. The AS-2259 consists of a pair of crossed dipoles on a common feedpoint. Je li netko možda stavljao napajanje na neko drugo mjesto jer sam na internetu našao i drugačije omjere. 00 €. Ground anchors. 204 - Low Radiation Angle Full-Wave Loop Antenna for 80m. It is used for military and paramilitary communications, broadcasting, [1] especially in the tropics, and by radio amateurs for nearby contacts circumventing line. name xxx qth winterthur near zurich this is my first qso on js8, funny . 7-m in the 1960s. TrademarkElite is the U. Even if I had the space to put up an HF antenna where I live, the noise floor being a constant S9+20 would make actually using it quite difficult. It is a half-wave long on the lowest frequency, and is fed from a coax cable through a transformer inserted in the wire at one-third from one end. THE OCF FD4 (FD3) WINDOM ANTENNA FD4 (80/40/20/10 m) The 4-band Fritzel model FD4 is a special version of a Windom antenna. America. 800 Watt FD4 multi-band antenna with 1:4 super balun Project for a multi-band antenna for the 80, 40, 20, 17, 12, 10 and 6 meter bands, including a 1:4 impedance transformer and a current balun handling 800 Watt with common mode attenuation up to 40 dB! Complete balun and 1:4 impedance transformer See full list on iw5edi. 5; 7; 14; 18; 28 MHz-en. ic7800 @ 100w microkeyer ii - heil proset elite - cushcraft r6000 and fd4 antennas - n1mm logger. The renowned “FD4” antenna was not an exception; Have a look at its VSWR specification on pages 13 and 14 of this brochure. THE OCF FD4 (FD3) WINDOM ANTENNA 19 may 2011. 3. On higher bands it did not work well. 0000 151. The half-size version is known as the FD3 40-20-10m antenna. This result suggests that sequences outside the C and GMR35H08 elements restrict fd4/fd5 expression to the ventral imaginal discs. But we are speaking about longwires here, not about an FD4. A wire antenna dipole is inexpensive, light and - depending on local conditions - can be. Today, many radio amateurs are using multiband Windom antennas with more thanTHE OCF FD4 (FD3) WINDOM ANTENNA FD4 (80/40/20/10 m) The 4-band Fritzel model FD4 is a special version of a Windom antenna. but nobody does receive me. One would argue that the stations worked would simply mail some funds to these DXpeditions to offset the lost income included with QSL requests. As low as: €240. Fritzel FD4 antenna, described by the late Dr. Coaxial Cable P R O D U C T S P E C I F I C A T I O N LDF4-50A Standard coaxial cable, 1/2", 50 ohm foam HELIAX (Wideband from 0. RST 579. The dimensions were the same as the multi-band Windom antenna, but fitted with a 200Ω (4:1) balun at its feed point and fed with 50 ohm coax at lower heights above the ground. Ožujak 2004, 14:46:50 ». This video provides background on what many of us believe to be the greatest off-center-fed dipole antenna ever created. Actually I could not get out of Europe on it. > I also know about the 6:1 balun but am looking for some info on the > overall length and the point of fed also the angle and height of the > ends of the antenna above ground. Fritz Spillner, DJ2KY, in 1971. Vertical antennas made of steel wire, monoband or multiband, with balun and radials.