80m Ocf Dipole Length

Off-center-Fed dipole Antennas is a curation of 13 resources about , OCF Dipole, The Six Meter OCF Sleeve Dipole Vertical, Center-Loaded Off-Center-Fed Dipole - 6 band, 80m OCF Dipole, Windom off center fed antenna 80-10 mt. Overall length from tip to tip is about 13″. Adjust elements for resonance in order from lowest frequency to the highest. The G5RV antenna is a multi-band center-fed dipole antenna capable of 1500 Watts. The center conductor and dielectric is not disturbed and the two separated braids are then fed with the Coax Feedline. The antenna can be mounted as a dipole or inverted vee. At this length, using stainless cable, the antenna becomes a resonant folded dipole on eighty meters. Theory books say a half-wave dipole for 40m should be at least a half-wave above ground (66 feet for 40m) and each leg a quarter-wave long - for 7. Some people might take issue with using the word "dipole" because the antenna has more than two opposing polarities along the length, but in my opinion it is perfectly fine. Also, worth noting is the pattern breaks up on 10M on the 43'er. The RadioWavz DX (OCF) Windom is a off center fed (OCF) dipole antenna that exhibits outstanding performance on multiple bands typically with out a tuner. The ½-wave vertical dipole brings in a great many signals that cannot be heard on the big horizontal dipole, and is considered a complete success. FD4 HF Dipole Antenna 80m 40m 20m 10m windom ocf wire balun unun multiband Windom antenna Length 42m for 160/80/40/20/1 7/12 Save 40m dipole to get e-mail. Introducing the W8AMZ 80–6m OCF / Windom Multi-Band Antenna using a 4:1 Balun and rated for 2 KW. 10-80m antenna requiring 40ft vertical height and 90ft of lateral length and 70ft min. The same is true of 10 meters; as frequency goes up, multibanding gets more quirky, and SWR curves and efficiency suffer. Pictures and some details of a multiband dipole antenna Added the 160m coil on the end. A typical OCF dipole is fed at 1/3rd of its length. The OCF dipole can work (with balun 4:1 or balun 6:1 and tuner) on 7, 14, 28 MHz. One separate dipole for each band. 2x10 M (2x33 FT) MID-LOADED DIPOLE. Do everything right, and 80 meter efficiency can be ≈6%. homemade 160m dipole. I've just put up a OCF dipole for 80m and above. 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. Expect ham radio confidence with the DX Flagpole and it's Vertical Dipole cousins down to 80M! Q. Its been a good performer for me and is resonant on 80m, 40m, 20m, 17m, 12m and 10m. 5 dBi peak gain on higher bands. 25, rising gradually to 2. This calculator is designed to give the total length of a particular dipole (inverted Vees) antenna, or one side of it, for the frequency chosen. 25=100 feet. Theory and modeling indicates it should add 2-3 dBd gain versus a simple dipole over “average/poor” soils. The metric formula is total length (in metres) = 142. The optimal height according to others is 15 meters, which also sets the feed point impedance as well. 80m overall length - 134' or 67' per side. I found that OCF antenna impedance is also dependent on height. The feedpoint excursions at a half wave length and harmonic frequencies are much lower than centre. The lowest feed-point impedance for a resonant ½ wave dipole is at the center but when we move off center the impedance increases. In the past, I've used an inverted vee with elements measuring 67 feet/20. Length Foot Wind MPH; D130J: 2m / 70cm / 23cm: 25–1300 MHz. It then calculates the number of turns on the helix for resonance. A special case of this, is the End-Fed Half-Wave (EFHW) antenna. The PRI 80WIN 80 meter antenna is shown above. The center of each Tee should be joined to the end of each of the dipole main elements. Although the OCF dipole has very broad band-segments, the VSWR-minima of either the 80m or the 40m-band can not be perfectly aligned to the respective band-centers. 160m/80m Broadband Antenna by K5GP A presentation to CTDXCC September 22, 2008 The 160m/80m broadband antenna design objectives were to have: 160 and 80 m antennas since I had no antennas for these bands, the antennas had to be hidden because of covenant restrictions, open wire feeders would be too visible to be allowed,. (QST, Oct 1926, "The Length of the Hertz Antenna" shows in line 2 of the table that a similarly installed random wire should use 423/f. saturn 5-80 80, 40, 20, 15, 10, (136 ft) multi dipole; saturn 5-80-short 80, 40, 20, 15, 10, (77ft) multi dipole dx ocfd (windom) dx 40 ocf short 37 ft 1500w ssb/pep 200w cw; dx 80 ocf short 77 ft 1500w ssb/pep 200w cw; dx 160 short 147 ft 1500 w ssb/pep 200w cw; dx ocf windom 40m,20m,10m; dx ocf windom 80m,40m,20m,10m; dx ocf windom 160. Homebrew 40/80 Trap Dipole Design This Antenna design was one that I used about 4 years ago, it worked exceptionally well on 80m and 40m. 5 KW 85' total length No Tuner needed. Performance on 80m is a bit of a compromise. We extended this length to 122 feet. They are at right angles to each other. << bam, ybØko/1: OCF Antenna, hal. The 40 Meter Off Center Fed Antenna (OCF40Q) is a great multi-band antenna. Our 7-Band antennas are OCF (off-center-fed), with a 45 foot leg and a 90 foot leg, totaling 135 feet. It is complete, cut, tuned, and ready to hang. net Abstract A coaxial-cable trap dipole antenna installed in the attic provides a surprisingly effective solution to HF operation on the 10, 15, 20, 30, 40, and 80 meter amateur bands at a QTH with restrictive covenants that prohibit outside antennas. For a recent SOTA activation I quickly soldered a short length of RG174 to the PCB pads which served its purpose for two activations,… 28/06/2017 in 23 cm 1296 MHz , 23cm antenna , Amateur Radio , Microwave , SOTA , SOTA Antenna , Summits on the Air , VHF DX. The Low Dipole: To enhance NVIS radiation “straight up” for regional comms, it’s useful to deploy a half wave wire in the near-field, on the ground under the half wave dipole to serve as a reflector. 5:1 on 6, 10, 20, 40 & 80m bands and can be More information. The dipole only beats the vertical broadside to the dipole, and then only rarely!! And this is with the dipole 300 feet above ground. to any other resonant antenna eg. With the Internet as a source of information, that is an easy policy to implement, since you can just insert a link to the material, and then write about. 96 feet for a dipole on 20m (each leg 16. Fullwave quad loop is: 72. Total length in feet. One constant used is 450. I have a dipole that is 148 feet long (74 feet either side of center). No ground plane or counterpoise is needed. The G5RV length of feed line and antenna is the lower limit in size. The 80m dipole was already on its 48 foot mast with a DX Engineering balun and original coax. 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. The lowest feed-point impedance for a resonant ½ wave dipole is at the center but when we move off center the impedance increases. The RadioWavz DX (OCF) Windom is ideal for those of you who do not use a tower and beam. Construction details are the same as the 7 and 4-Band antennas, the 8-Band just has more wire so it can work 160M. 6 MHz and you arrive at an overall length of 130'. Tie your dipole feed lines together in the hamshack. 80m Band SWR on 80m OCF Dipole Building a "Dirgly Balun" to Make a Windom Antenna from a RadioWavz OCF Dipole. Ham Radio Dipole Transmission Line. This is not really a Windom at all, but an Off Centre Fed dipole with a radiating feed line. I went to my old spot on the river Rhine today where my 3 favorite trees are standing and tried out my new homemade antenna, I have made a simple 1/2 wave dipole with a 1:1 ferrite rod balun and 8m of RG 58 u, for 80m with switches along the wire so I can also use it on 40m, I had 5 contacts on 80m running 4 watts but none on 40m as the band. I've also found a calculation online for the lengths of OCF/windom type dipoles, and it is as follows: (Long side of ariel) 468 divided by the Frequency in MHz - multiply the answer by. Off-Center Fed Vertical Dipole design means no radials, >90% efficient or better across 80m to 10m. It then calculates the number of turns on the helix for resonance. The OCF will never have the gain. Since it is a full wave antenna, you get twice the wire of a dipole into and onto the air. Construct a multi-band off-center-fed (OCF) dipole covering the 40, 20, 15, and 10 meters amateur radio bands, and possibly the 6 meter band (but that is considered a bonus band, outside the main project objective. The RadioWavz DX (OCF) Windom is a off center fed (OCF) dipole antenna that exhibits outstanding performance on multiple bands typically with out a tuner. ATS3, 88' doublet up 60'. The OCF-3K80 dipole will work well on the 80 40 ,20, 17,12 and 6 meter ham bands without an antenna tuner. UV insulated stranded wire The RadioWavz DX (OCF) Windom is ideal for those of you who do not use a tower and beam. The Par End-Fedz are a full length half wave dipoles, but with an important difference. I've also found a calculation online for the lengths of OCF/windom type dipoles, and it is as follows: (Long side of ariel) 468 divided by the Frequency in MHz - multiply the answer by. After spending some time modeling OCF antennas, the closest antenna I could find to a true multi-band dipole with reasonable SWR on most bands had an 80%/20% leg length and 200-ohm feedpoint. Off-Center-Fed (OCF) Antenna FAQ (Frequently Asked Questions) Q:How do I erect a Buckmaster OCF antenna? You need an environment free from long lengths of metal; any length of metal that happens to be resonant on a ham band can rob signal from your Buckmaster OCF. But it turns out, If I make the long end of the 80-6m OCF the short end of the 160-6m OCF, and add the required length to short end the long end of a 160-6M OCF, It would be the same. Princeton Windom Antennas Amateur Wire Antennas. The dipole was very noisy compared to my vertical Hustler 6btv and at times was unusable due to extreme noise levels on 80m. The OCF-3K80 dipole will work well on the 80 40 ,20, 17,12 and 6 meter ham bands without an antenna tuner. The following PDF files maybe of interest to you then, these are some of the better performing Multi-Band HF antennas they been around for years. Prices are subject to change without notice. Although the traditional OCF dipole had very broad band-segments, the VSWR-minima of either the 80 m or the 40 m-band could not be perfectly aligned to the respective band-centers. Home Made Off Center Fed Dipole. Not even a dipole for 40 meters will fit behind the house. On 40 and 20 the SWR is close to perfect. 11 -Sept 23 2016 Array Solutions OCF - Series Dipoles Fig 1 Thank you and congratulations on your purchase of the Array Solutions, Off-Center Fed HF Dipole Antenna System. The main issue is that there is huge BCB breakthrough from Brookmans Park which is in LOS, so I am using a high pass filter at the transceiver to reduce this to a reasonable level. In my case with the coax run at a 90 degree angle away from the antenna, this type of choke sufficed. This type of antenna is suitable for single band, narrow bandwidth use. dipole length (in feet) = 468 / f (MHz) So that will be 32. The OCFD in incapable of harmonics. Homebrew 40/80 Trap Dipole Design This Antenna design was one that I used about 4 years ago, it worked exceptionally well on 80m and 40m. So the measurements are based on a 40 meter 1/2 wave dipole. The half-wave dipole is very simple to construct. Smart Design, Premium Rugged Quality, All Band OCF Vertical Dipole Antenna, No Radials Required for maximum performance. It is a heavy duty QRP/Low Power antenna that uses #14 wire instead of the usual #16 wire used by our other QRP/Low power models. Our wires start at 44 feet but longer length is recommended for coverage of 80m or even 160m band. The Balun matches the Balanced Antenna into the Unbalanced Coax Cable. WINDOM ANTENNA. Fullwave quad loop is: 283. Put up an OCF 7 in a similar inverted V, even higher than the ZS6BKW. I've entitled this section OCF dipole because, at least on 80m, this is exactly what it is and it also represents the worst case for unbalance. 1 Dipole (λ/2) Antennas A dipole antenna most commonly refers to a half-wavelength (λ/2). Calculations for the wire lengths can. THE YO-YO-END-FED ANTENNA - CHF 34. Resources listed under OCF Antenna category belongs to Antennas main collection, and get reviewed and rated by amateur radio operators. The balun is offset 3 feet from my tower at the 36 foot level. The OCF-3K80 dipole will work well on the 80 40 ,20, 17,12 and 6 meter ham bands without an antenna tuner. Construct a multi-band off-center-fed (OCF) dipole covering the 40, 20, 15, and 10 meters amateur radio bands, and possibly the 6 meter band (but that is considered a bonus band, outside the main project objective. I have no problem now with RF in the shack using the doublet. 5 Attic OCF HZ Dipole. On 40 and 20 the SWR is close to perfect. On higher bands, the antenna performs well too. I have an OCF antenna at 45 feet that I use for 80 and 40 meters. The RadioWavz DX (OCF) Windom is ideal for those of you who do not use a tower and beam. Our 8-Band antennas are OCF (off-center-fed), with a 90 foot leg and a 180 foot leg, totaling 270 feet. to any other resonant antenna eg. I found that OCF antenna impedance is also dependent on height. And yes you can bend any half wave antenna (dipole or end fed within limits) into a V, Inverted V, vertical or inverted L to name a few. The Short Dipole "On Coils" There is very popular method of making a short dipole ("physically shorter than normal" half-wave dipole) resonate at a given frequency. I had LMR-240 Ultraflex on hand for the 50 ohm piece. Only operated 1/2 hour, only 40 meters. The advantage of a 1/2 wave OCF dipole fed 1/3 of the way from one end is that it can be used on the fundamental frequency and its even harmonics. 80m Loaded Dipole This Antenna came about the need for an 80m antenna to supplement a SteppIR Antenna at VK1HM. Its overall length is 1. The 40 Meter Off Center Fed Antenna (OCF40Q) is a great multi-band antenna. The OCF-3K80 dipole will work well on the 80 40 ,20, 17,12 and 6 meter ham bands without an antenna tuner. You get an amazing (up to) 11. I attached a porcelain egg insu-lator to the far end of the dipole (left end of. Dipole Models There are 3 configurations. The RadioWavz DX (OCF) Windom is ideal for those of you who do not use a tower and beam. The 1/4λ transformer ensures that the antenna is resonant in addition to a conventional W3DZZ on 14 MHz. Electric Current on a half-wave dipole antenna. So I'm no longer using this attic antenna for 80m but it's working great for 40m and above. The half-wave dipole antenna is as you may expect, a simple half-wavelength wire fed at the center as shown in Figure 1: Figure 1. Full 80m-band coverage. A typical OCF dipole is fed at 1/3rd of its length. The lengths of the dipole legs should be in a ratio of between about 2:1 and 3:1 to provide tunable impedances for the ATU. All AUS prices include Australian GST (10%). How well and antenna works is a difficult question to answer. If you cut too much off, you have the option to cut the cable ties and feed more coax through the former or solder a short length of wire to the existing core, and start again! Please feel free to offer constructive feedback. FD3 (40m-20m-10m) OCF antenna by G8ODE The FD3 OCFD antenna is modelled using MMANA-GAL basic freeware antenna analysis software. com 7 Band OCF Windom Dual core Current balun 3KW Poly-Stealth Antenna HF. The first of these is that the power gain of a long wire antenna as compared to a half wave dipole is not considerable until the antenna is really long (its length measured in wavelengths rather than metres of feet). RADIOWAVZ/ICOM DIPOLE SLIDER CALCULATOR: A Free Download! A must have for all go kits, and to have around the shack, the RadioWavz/Icom Dipole Slider calculates dipole antenna length for your favorite band at the turn of the wrist. Prices are subject to change without notice. Changing the length of the feedline will change the resonance of the system (the wires in the sky and the feed line). The advantage of a 1/2 wave OCF dipole fed 1/3 of the way from one end is that it can be used on the fundamental frequency and its even harmonics. Choose from 12, 16, 20 and 28 footers! (flag or non-flag) that all operate from 80-6 meters with impressive efficiency. 8 MHz, at just over a quarter wave length it will still give usable access to this band. Buckmaster OCF Dipole Antennas. The OCF-3K80 dipole will work well on the 80, 40 ,20, 17,12,10 and 6 meter ham bands with no need for tuning. Don't kid yourself, this isn't as easy as it sounds. The 3/2 wave 15 meter antenna (really the 40 meter dipole) has significant gain and is about 150Ω resistive depending on height. This is not really a Windom at all, but an Off Centre Fed dipole with a radiating feed line. In fact it wasn’t anyway as it had been a nice sunny, warm, but not too warm, afternoon out. Typical dipole lengths for the bands from 40m to 6m are given in Table 4. It reduces the overall length of the antenna by 40%. 57 - Five-Bands No-Tuner Antenna. A 20 meter through 10 meter Vertical Dipole Antenna. Overall length from tip to tip is about 13″. Design Parameters. I also used a 20 meter dipole in my attic successfully back then. Dipole Antenna Calculator. The antenna can be mounted as a dipole or inverted vee. Portable operation could not be easier. Introducing the "All-Band" Doublet: What the Student and the Instructor Should Keep in Mind L. 2x10 M (2x33 FT) MID-LOADED DIPOLE. 73's, Joe N2DAB. Operation with the new Delta Loop. Introducing the W8AMZ 80–6m OCF / Windom Multi-Band Antenna using a 4:1 Balun and rated for 2 KW. I have a dipole that is 148 feet long (74 feet either side of center). Tuning the antenna is simple. Extended double Zepp is: 89. It is a heavy duty QRP/Low Power antenna that uses #14 wire instead of the usual #16 wire used by our other QRP/Low power models. High current, low voltage at center; low current high voltage at ends. An easy project I was able to tackle in one day. The input impedance of the half-wavelength dipole antenna is given by Zin = 73 + j42. A Broadband 80/160 Meter Dipole An easy to build single wire antenna for 160 and 80 meters with a better than 2 to 1 swr across the 80 meter band. Off-centre-fed dipole (OCF dipole) As the name suggests, the OCF dipole is not fed from the centre. Be sure to put a 4:1 CURRENT balun at the top feed point. For the most part, this is true. MFJ-1778 - G5RV Wire Antenna - Multi-Band center-fed dipole antennas. Look for me beginning tomorrow from the island of Bonaire in the Caribbean as PJ4/K4BAI and in ARRL DX CW next weekend as PJ4A. Our wires start at 44 feet but longer length is recommended for coverage of 80m or even 160m band. Try inserting a short length jumper (3 ft) to see if the rig's built in tuner will match. I ask this mostly because I would need very long coax for 160m half wave OCFD. Mind you signals were well down on 80m as the antenna is too short. of mounting rope. So I'm no longer using this attic antenna for 80m but it's working great for 40m and above. The longest dipole that I can fit on my terrace, albeit with a dog leg between the dipole halves, is 2 x 10 m (2x 33 ft), i. (A drawing to show the progression from standard dipole, to Capacity hatted, end loaded, vertical dipole) As the Capacity hats get larger, the resonant length shortens. For an 80-10 meter OCF dipole antenna, divide the ½ wavelength standard of 468 by the lowest operating frequency of 3. I screwed a length of thin wall electrical metallic tubing (EMT) to the tree trunk and attached four heavy "screen door" springs to the EMT. The previous 80m antenna was de-tuneing the SteppIR and so one of the requirements are to have no resonance at any other frequency. All information, images, and documents on this website are the sole property of MFJ Enterprises, Inc. 25=100 feet. Dipole Antenna Calculator. It was originally designed to operate as a 3/2 wavelength center fed antenna for 14 MHz, but amateurs soon discovered it would offer reasonable performance on many other bands. Still testing both but so far the ZS6BKW has been most impressive on 40 and 20 meterers (will tune on 80 but with higher SWR due to shorter length. Dipole Antenna Length Calculator. The 160 leg is 56″ long and made of 14 gauge insulated wire. The feedpoint excursions at a half wave length and harmonic frequencies are much lower than centre. An End-Center-Fed Vertical Dipole Behaves like a center-fed vertical dipole – ZO ~ 70 ohms, so 75 ohm coax is the best match Top half is λ/4 wire Outside of coax shield is the bottom λ/4 – Use Vf ~ 0. Also, worth noting is the pattern breaks up on 10M on the 43'er. A 1 to 1 balun does not affect the matching, 75 to 50 ohms or whatever, not what it is designed for. In fact it wasn’t anyway as it had been a nice sunny, warm, but not too warm, afternoon out. Antennas for CB radio bands 11 meter. It is fed with 52-ohm cable and a 4:1 balun at the feed point. Some sources will suggest that the number is 3 to 5 percent shorter than the length of the dipole. The antenna can be mounted as a simple dipole or inverted veeThe OCF-3K40 is complete and ready to install. The RadioWavz DX (OCF) Windom is ideal for those of you who do not use a tower and beam. There are no complicated wires or losssy coils to deal with. The RadioWavz DX (OCF) Windom is a off center fed (OCF) dipole antenna that exhibits outstanding performance on all bands. Enter the desired frequency and select the desired calculation from the drop box. Cumbersome cage dipoles or load switching arrrangements deliver only partially satisfactory results that are easily outperformed by the OCF dipole [1]. 5MHz and you get 130'. The OCF Dipole is a horizontal wire with a coaxial feed and coupling transformer (often called a balun) attached offset from the centre of the dipole. Another way to say this is a 100 delta SNRs comparing a full length. Hence, the half-wavelength dipole antenna's length is 0. It works much beter than an 80 meter dipole antenna at 25 feet usually. There is a way to make a half-wave dipole and only cut it two times, initial cut and final tuned cut. The only can be tweaked to work on frequencies near even thing they share is the fact that neither is fed at the harmonics. The parallel dipole uses several dipoles joined together in the center and fed with the same cable. The longest dipole that I can fit on my terrace, albeit with a dog leg between the dipole halves, is 2 x 10 m (2x 33 ft), i. So the measurements are based on a 40 meter 1/2 wave dipole. You get an amazing (up to) 11. 25 one side. A half-wavelength radiator has a high impedance (high voltage, low current) at the feedpoint. Fullwave quad loop is: 283. I am contemplating either leaving the Zepp up for the 80M and 40M bands or replacing it with the G5RV. The main issue is that there is huge BCB breakthrough from Brookmans Park which is in LOS, so I am using a high pass filter at the transceiver to reduce this to a reasonable level. The lengths of the dipole legs should be in a ratio of between about 2:1 and 3:1 to provide tunable impedances for the ATU. The parallel dipole uses several dipoles joined together in the center and fed with the same cable. 5:1 on 6, 10, 20, 40 & 80m bands and can be More information. G7FEK Limited Space Antenna G7FEK Multi-band “Nested Marconi” Antenna - 2008 Version (rev 5) This antenna was first conceived as a simple dual band antenna in 1988, in an attempt to achieve sensible dual band operation in a small garden of 14m (46 ft) length. Also, designs that do better on 80m, lack 15m. Bow-Tie Dipole Antenna 14 20. 25=100 feet. Ham Radio Dipole Transmission Line. One constant used is 450. 14 one side. Buckmaster OCF 6 Band Dipole VS Standard 20m Dipole This is a very non-technical review of the receive capabilities of the Buckmaster Off Center Fed Dipole vs an eBay 20m Dipole from seller “big_r_world”. – Daytime - 80, 60 or 40m – Nighttime - 80 or 160 m. But to your point, the off center fed dipole is a very effective antenna that is basically a more refined version of what i lay out in this article. I originally cut each element to 5ft in length. 2 = 33 feet. The dipole was very noisy compared to my vertical Hustler 6btv and at times was unusable due to extreme noise levels on 80m. 10-80m antenna requiring 40ft vertical height and 90ft of lateral length and 70ft min. Somewhere between 25 and 35% it'll work, again depending on ground conductivity, etc. But to your point, the off center fed dipole is a very effective antenna that is basically a more refined version of what i lay out in this article. Total length in feet. of mounting rope. OCFD, 40/20/10/6M, DIPOLE, 300W. Signals seemed weaker than usual. The first (and most important) goal was to get the FULL 40 meter band at less than 1. George, VY1GP, made a really nice video production of his pitch. At this point I’m questioning whether it would even be feasible to try to install a dipole long enough to cover 40m. 80 meters= minimum efficient length 80*1. of The ARRL Antenna Book and was interested to see a design for a 2-ele-ment quad. The dipole elements are 15. It was originally designed to operate as a 3/2 wavelength center fed antenna for 14 MHz, but amateurs soon discovered it would offer reasonable performance on many other bands. In some instances it may be required to use a 1:1 Guanella choke. rotary dipole 80m. Taking one vertical angle and frequency with another, the RadioWavz DX (OCF) Windom is Omni directional. L = \frac {142. February 7 of 2010 was a quiet Sunday. I've just put up a OCF dipole for 80m and above. The ratio - 1/3 / 2/3 length using a true 4:1 balun causes the short end to act like a reflector. Design Parameters. 5:1 across the 75, 40 and 20 meter bands. A feed line is attached to an optimum point along the dipole by a BALUN. Does anyone have a Hustler 5BTV installed on the ground with radials. What attracted me to try a Delta the most was the Delta's reputation for working well close to the ground. A special case of this, is the End-Fed Half-Wave (EFHW) antenna. Adjust elements for resonance in order from lowest frequency to the highest. The 6:1, model 6113 should be used if the OCF will be cut for an 80m length or less and the feedpoint will be at or above 60 feet. I decided to build a 80 meter, half wave wire antenna that takes full advantage of the phone portion of the band known as 75 meters, also this antenna will not need a tuner. Buckmaster OCF 6 Band Dipole VS Standard 20m Dipole This is a very non-technical review of the receive capabilities of the Buckmaster Off Center Fed Dipole vs an eBay 20m Dipole from seller “big_r_world”. Lower mast heights will work but the antenna may not be omnidirectional (e. The local (Groningen) 84,7% solar eclipse begins at 09:33, maximum at 10:40 and ends at 11:51. 5 KW 85' total length No Tuner needed. The first is an 80m dipole kit with instructions to build a very rugged legal limit half wave dipole. If you don't see what you want, don't hesitate to ask. Since the resonant length of a given element in the presence of the others is not the same as a dipole by itself, tuning can be a tedious and difficult procedure. This antenna is made for the Ham operator that ís looking for a compact dipole antenna to work on 40M. The classic OCFD is fedat 2/3 - 1/3 of the length Both a standard dipole and the. Still testing both but so far the ZS6BKW has been most impressive on 40 and 20 meterers (will tune on 80 but with higher SWR due to shorter length. I just tested one out yesterday, where I start with a 40m dipole and add loading coils and extension wires. K1POO 4 Band Off Centre Fed Dipole (40-20-15-10m ) MMANA-GAL K1POO Antenna model’s 3D far field results The antenna at 8m height above real ground 5mS/m and dielectric 13, SWR ref 200Ω. The only can be tweaked to work on frequencies near even thing they share is the fact that neither is fed at the harmonics. The bazooka worked well but was a single band antenna and I >would replace it after any 160M contest with either a Carolina Windom or a >80M delta loop. The Spiderbeam pole is not strong enough to support a balun at its top so I use 10m of 300R TV ribbon cable to connect the antenna arms to a balun mounted near the base of the Spiderbeam. It consists of an 85ft wire fed against a 17ft counterpoise (attached to the earth point on the ATU). On the HF bands adding a remote atu made very little. The OCFD in incapable of harmonics. It's fairly close to the ground so I'm not suprised it's SWR on 80 is a little high but still useable. Theory books say a half-wave dipole for 40m should be at least a half-wave above ground (66 feet for 40m) and each leg a quarter-wave long - for 7. I just installed one and cut 4 radials to recommended length for the 80m/40m/20m bands. Feeding the transformer with a remote atu made about 2dB improvement on 80m over the transformer alone. New Shack: Below are some pictures of my. The balun /. 2x10 M (2x33 FT) MID-LOADED DIPOLE. 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. If you have room for an 80m dipole, you probably have room for a 160m antenna as well. The antenna is designed to be fed with 50 or 75 Ohm Coax Cable of most any length with a Balun. 5 to 28 MHz does not use traps or require antenna coupler. Tuning is carried out in the same way that you would tune a standard 40 meter dipole. WINDOM ANTENNA. one quarter (1/4) wave is the minimum height above ground for effective performance. The previous 80m antenna was de-tuneing the SteppIR and so one of the requirements are to have no resonance at any other frequency. I originally cut each element to 5ft in length. I had to wrap the fiberglass pole with pipe insulation and then tape over it because when I went to tighten the clamps it sounded like I was crushing the pole. Theory books say a half-wave dipole for 40m should be at least a half-wave above ground (66 feet for 40m) and each leg a quarter-wave long - for 7. The idea is that for a given ham band there are min and max frequencies which are easily converted to half wavelengths by the famous 468/f generally used by hams for dipole lengths. It needs no tuner on 40m, 20m and 10m. The idea is that for a given ham band there are min and max frequencies which are easily converted to half wavelengths by the famous 468/f generally used by hams for dipole lengths. I hope that this post provides some useful ideas for HAMs contemplating the installation of their first HF antenna. We specialize in wire antenna systems. 5:1 on 6, 10, 20, 40 & 80m bands and can be operated without an antenna tuner. SORRY - Temporarily out of stock. On higher bands, the antenna performs well too. This would be 109. Off-centre-fed dipole (OCF dipole) As the name suggests, the OCF dipole is not fed from the centre. So how does it perform. The only can be tweaked to work on frequencies near even thing they share is the fact that neither is fed at the harmonics. Band width:80m,40m,20m,10m Typically with out a tuner. The Multi-Band OCF The Trap Antenna works well on 80M and 40M but is it possible to get more band coverage with an antenna of comparable length, i. The G5RV is a 102 ft center-fed dipole fed with ~30 ft of 300 ohm twinlead plus coax the rest of the way to the shack. OCF short vertical dipole for HF. Length Foot Wind MPH; D130J: 2m / 70cm / 23cm: 25–1300 MHz. Antennas:160m vertical (almost). It covers the 80 meter through 6 meter Amateur Radio bands and can handle up to 100 watts SSB, 25 watts digital. New Shack: Below are some pictures of my.