Ocf Dipole Inverted V

literally tens of thousands of these marvelous RADIO WORKS' OCFD MAX™. Right: 3D far field pattern, with 2D elevation "slice" highlighted. That got me thinking. 73 de Mel. Variable Folded Terminated Dipole. The Smartech 27OCFDV dipole belongs to the family of the Off Center Fed antennas. Buckmaster OCF Antennas are made from the best quality materials and are designed to give you years of trouble-free service. The standard OCF dipole is in the CW portion of the band. Equipment: Icom IC-7300, 100W, TH6DXX for upper three bands, One element delta loop for 40m, Inverted V dipole for 80m, Inverted L for 160m, Log N1MM + 73 ES GL DE Robi, S58Y. Hi! Nice summer contest, long just enough. Try to mount the antenna with the feed-point at about 35+ feet above ground and the ends from 8 to 10 feet or more above ground if mounted as an inverted vee. 0B of the Berkeley High Resolution (BEHR) Ozone Monitoring Instrument (OMI) NO 2 product is designed to accurately retrieve daily variation in the high-spatial-resolution mapping of tropospheric column NO 2 over continental North America between 25 and 50 ∘ N. 160 Meter Inverted-L Bazooka Antenna A DOUBLE BAZOOKA antenna is an extremely broad-banded Half Wave Antenna that can operate efficiently across an entire Ham band with little change to the SWR. I use an ATU to match. Above right: The red trace is a G5RV inverted V with the apex at 12m and the ends at three metres. 15 dBi) in the horizontal plane (2). With the EFLW-1K, I'm able to talk across all 48 and into Canada with ease with good band conditions. Buy OCF Dipole 7 Band 80-6 Meters Antenna Poly-Stealth 61 core: Antennas Antenna is in inverted V with balun at 30 feet and ends at 20 feet. In terms of limited space and cost, it's probably easier to set up a horizontal antenna (or an inverted V like a G5RV or OCF) than a vertical simply because it's easier to string a wire through some trees than it is to secure a flagpole or tower against gravity and wind loads. com in a single category. It also transforms the unbalanced coax to a balanced feed. The OCF dipole is usually installed in an inverted-V configuration so the ends do not need to be very high off the ground (~10 ft is good). DX-OCF SWR chart thru 6 meters Alpha Delta Model DX-OCF Off-Center-Fed (OCF) Dipole 300 Watt antenna (3000 watt Model DX-OCF-HP may vary slightly) Center height 32 feet, end height 8 feet Erected as an inverted "V". The 450 Ohm ladder line is about 10 feet long as it exits my house through a second floor window. This link is listed in our web site directory since Tuesday Jun 9 2009, and till today "Off Center Fed Inverted V Dipole" has been followed for a total of 1675 times. Right: 3D far field pattern, with 2D elevation "slice" highlighted. Like my other dipoles, it is fed with 72 ohm coax, but this time with a few turns of the coax rolled into a coil at the central feed point to act as a coax balun. Not enough room fo 80 meters. dual band dipole - 40 and 15 metre bands Dual band dipole for 40m (7 - 7. Working DX is a pleasure as I hear more stations and have 1+ s-unit lower noise when compared to my prior wire antenna. The antenna can be mounted horizontally between two support systems, or as an inverted ‘V’ using a single central support mast. 6-80 Meter OCF Dipole Antenna by Alpha Antenna. An multiband off-center feed (OCF) dipole is a cut to be a half wave on the lowest frequency you intend to us with the feedline being connected somewhere other than the center of the antenna. See more ideas about Ham radio, Ham radio antenna and Ham. Use on 160 Meters as Marconi with tuner and ground. Buckmaster OCF Dipole Installation Diagram (Courtesy Buckmaster) T2FD Terminated Folded Dipole Inverted V TFD. In many practical situations it is possible to operate the dipole satisfactorily without one, but there may be a slight increased risk of interference if one is not used. This inverted V-antenna is easily installed on a non-conducting mast. Enter your search keyword. inverted-V you might be better off putting each leg across the side of the roof rafters to reduce the angle. Inverted Vee This is just as it sounds, an inverted or upside down "V" shape. Typically no tuner is required for 40, 20, lower 10, bands. Same dimensions and specs as the original J-Pole but with a screw connector in the middle for easy transport and storage. This is a popular antenna system; many have been built using DX Engineering baluns. 6m from the edge of Element. ) Buckmaster 8-Band OCF Dipole Antennas are 270 feet (82 meters) long and work on 160 (tuner may be required), 80, 40, 20, 17, 12, 10, & 6 meters. Azimuth radiation pattern Guanella 4:1 Dual Core Current Balun. Basic setup is an Icom IC-718, MFJ 962C manual tuner and ALS-600 solid state amp. The vertical dipole or its electromagnetic equivalent, the monopole, could be considered one of the best antennas for land mobile radio applications. However, it does have 4 partial nulls, while the half-wave dipole has only two. Covers all bands, 160-10 Meters with antenna tuner. How do we get back the 160 meter resonance? By placing a series. Includes tips for construction, mounting and tuning. A feed line is attached to an optimum point along the dipole by a BALUN. I too use an OCF dipole with the top 1/2 wave long on 75m. It can be installed as an inverted V or as a straight dipole. Apparently, OCF dipole designs had so far been a compromise between these three bands. OCF Dipole 7 band 80 -6 Rick on 27th Mar 2018 You are not going to find a better antenna than this one. 1109/ACCESS. The 40/80/160 Meter Coil-loaded Inverted V Dipole Antenna. BBTD Inverted V Pyramid 3D Model Geometry View BBTD Inverted V Pyramid (Large Size) Model Dimensions The Broadband Butterfly Terminated Dipole antenna (BBTD) was invented by Bonnie Crystal (KQ6XA). It works pretty well too. This could be 50 ohm types such as RG58, RG8X, RG8, RG213, or 75 ohm type such as RG11, RG59, RG6 or even 75 ohm twin lead. I now live at a new QTH, my kids have left home and all of the tv's and other electronics in the house have been replaced over the last 5 years apart from the microwave but the problem remains s5-s7 static noise on 40-17m 12 & 10 are clear with only one common factor my OCF. When set up as an inverted-V the center of the dipole is lifted up and the wires of the dipole are sloping downwards. Mine has a single fire feed like the old fashion Windom worked against some insulated radials, some ground rods, and the cold water pipe. Use as inverted vee or sloper to be more compact. An inverted vee antenna is a type of antenna similar to a horizontal dipole, but with the two sides bent down towards the ground, typically creating a 120 or 90 degree angle between the dipole legs. Feed point impedance is high and requires a 4-1 balun. I too use an OCF dipole with the top 1/2 wave long on 75m. Right now I have a off-center fed dipole at 28ft. A high and clear dipole should have about 72 ohms of input impedance and be a great match for 75 ohm coax. When set up as an inverted-V the center of the dipole is lifted up and the wires of the dipole are sloping downwards. One separate dipole for each band. Includes tips for construction, mounting and tuning. Find great deals on SOTABEAMS for Walking Pole Guying Kit. I use a 40m OCF (Pic on Profile) I call it a 40m OCF because that is what it is closest to. MY-DP160-10m Single band half wave dipoles with 1:1 BALUN 3kW This is a single band wire dipole with 1:1 Balun /3kW for amateur radio bands 160-10m. Features include: Heavy duty stainless 1/4 inch center threaded, cemented with lock nut eyebolt supports the off center enclosure for years of trouble free service. It should be mounted as an inverted-V. Use on 160 Meters as Marconi with tuner and ground. 5 across both bands. Windom, W8GZ who described it in September 1929 QST. The feeding point of this antenna is located 13. Richard warned of significant risk of RF on the outer (inner?) braid of the coax. In this video, "kloxieman" shows us how he installed the G5RV as an inverted V using a 30-ft/9. These Are A Very Efficient Multi Band Antenna. Off Center Fed Dipole Antenna for the HF bands and 6 m, from 3 to 54 MHz. OK, 40 and 15 m from one dipole doing a little better, but not good enough. com FREE DELIVERY possible on eligible purchases. 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. An Off-Center-Fed (OCF) dipole with total span of 84+17=101 ft, with the feed point at 1/6th of the total span (101 / 6 ≈ 17 ft = 17%) from one end ( = 83 / 17 OCF). For the antenna layout below, the center capacitor is 15 pF at element 3 between elements 2 and 4 and a 4:1 balun feeds the antenna between elements 1 and 2. A large size BBTD Inverted V Pyramid configuration is modeled in 4NEC2. Weight: 25 lbs. The Wire Size can range from 16 AWG to 12 AWG. Dipole Cousins Inverted V – Only needs one support. This is particularly true at our fairly low 40 foot test height. There is a way to make a half-wave dipole and only cut it two times, initial cut and final tuned cut. I might be building a OCF myself, what do I got to lose and if it works I save big bucks over the cost of the Buckmaster. Yes, it is Off-Centered. None of these work very well on the lower frequency bands unless you can get them up to about 60 feet or more (at least in the center). It also transforms the unbalanced coax to a balanced feed. I am providing this page because the dipole antenna is often overlooked nowadays as an effective means to getting on the air. An inverted V half-wave dipole doesn't do this, so if you must have an inverted V for 20m, use a half-wave dipole, not a G5RV or OCF (Windom). A 40 m center fed dipole will not work 20 m or 10 m. Today I built and put up a OCF inverted-v dipole using with a 133 foot total length of #14 insulated THNN with the short leg cut to 44 feet. Not perfect for everything, of course there is a trade off. The Moxon is up around 9 meters. The angle between the two legs us usually between 90 and 120 degrees. That is, install it an angle with the rafters. Use as inverted vee or sloper to be more compact. Icom 7300 @ 5W and OCF Dipole. Above: Screen shots from several EZNEC v. I plan to take down the DX-LB sometime in 2014 and replace with OCF 80m dipole, or possibly a short vertical. Typically no tuner is required for 40, 20, 17, 12, lower 10, and lower 6 Meter bands. Length approximately 135 feet. HF antenna is a homemade (13,8 / 27,7) meters OCF dipole (Windom) with a 4:1 current balun, working on 80, 40, 20, 17, 12, 10 and 6 meters. It should be mounted as an inverted-V. which is a off-center fed, unbalanced dipole. As it turns out the QRM in the attic was a little to much. are possible. B uilt to last! Engineered to out preform! RadioWavz Wire antennas are the simplest practical antennas from a theoretical point of view; current amplitude on such an antenna decreases uniformly from the maximum at the center to zero at the ends. The End-Fed Inverted “V” is a good compromise between performance and ease of installation since it requires only one center support, has a reasonably small foot-print, and provides good sky wave propagation. Hung in a slight inverted V configuration. The biggest and best ham radio classifieds on the web! Buy, sell, trade HF and VHF equipment, towers, antennas, rotators and more!. Ver2cal'Wire'Antenna' • Actually'a'ver2cally'orientated' resonate'1/2'wave'dipole'with' the'earth'being'the' return ' half' • Due'to'poor'ground' conduc2vity'a. I plan to take down the DX-LB sometime in 2014 and replace with OCF 80m dipole, or possibly a short vertical. The RadioWavz DX (OCF) Windom is a off center fed (OCF) dipole antenna that exhibits outstanding performance on all bands. The best performing 80 M aeriel I have had by far was an inverted V with a hairpin match but it only worked on 80 and did it very well. Takes up less space. The balun is offset 3 feet from my tower at the 36 foot level. moved to VK1HW. This pattern will reverse when the feed-point is moved as little as 5% off center. The UHMW mounting plate/center insulator can be mounted in a variety of ways. 4 OCF Wide L-Dipole? To answer this question a generalized OCF antenna model was developed where where any length of wire could be bent at any point and each arm could be set at any angle. 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. Convertible 68 foot section NOT removed. They also have an omnidirectional radiation pattern. Ever wonder why successful DX-seeking stations so often use vertically polarized Verticals or Inverted-Ls on those lower bands? And why horizontal dipole-type antennas are most often seen for use on the higher shortwave bands? Even loop designs, intended for DX chasing on these lower bands, most often employ vertical polarization. Luckly, we had a break in the cold with a warm day, so I took the dipole out of the attic, grabed my 12' painters pole, 50' of the coax I got with the swr/power meter from Ebay, some old line from my sailboat, and put my dipole up in an inverted-v. If you’re like me, you don’t have enough real estate for that amount of wire!. Interesting World Wide DX 7-Band HF Off-Center-Fed Dipole Antenna. Link to Article. Steel whip on car 96 " or just a 40m ham stick. I began by looking at a classical quarter wavelength "ground plane" antenna at nine feet (safe height for radials). The G5RV works as follows: On 20m the dipole is 3/2 wavelengths long. (OCF) Dipole •Based on the Windom antenna. It should be mounted as an inverted-V. 003 Ohm resistance fed at the base with the MFJ 998 is a compromise, full bandwidth on 180 to 20 meters. 26 feet from one end. Attach twine to end of wires then use them to also be the guy wires to hold the mast vertical. That is, install it an angle with the rafters. I have also used it as a slopper and inverted V at field days. The dipole antenna is very well known among the amateur community so this may be old hat to many. It's performance compared to the dipole has been very impressive. The dipole worked pretty well as most resonant antennas do; however, after considering some other alternative wire designs I decided to try a full wave Delta Loop. 45MHz) bands at my previous residence in Melbourne, Victoria in 2004 For my first HF antenna I selection a basic 40m band dipole primarily as a simple antenna that provided access to one the most versatile amateur HF bands. Half wave dipole - inverted V configuration (approximately -4. The Breakaway 2 meter J-Pole is the same antenna as the original model but with a two piece design. A feed line is attached to an optimum point along the dipole by a BALUN. The size of the antenna makes a Half wave length on 80 meters, and with the traps a half wave on 40m with a SWR (standing wave ratio) of 1:1-1. 6 QSOs for 6 states. Dave Tadlock. It also transforms the unbalanced coax to a balanced feed. off the ground • All balanced antennas require a Balunif fed with coax. SWR is very high on 160m (expected) but it receives really well. To connect aluminum or steel wire to copper, make a couple of short #14 solid copper pigtails, twist them tightly into the aluminum or steel elements at the feedpoint, then solder an SO-239, or direct coax feed, to the copper tails. The following data are for the far field radiation patterns and 3D color views of an End Fed Half Wave Inverted-V antenna with the high point in the center at 40 feet and the ends about 10 feet over ground. The vertical dipole or its electromagnetic equivalent, the monopole, could be considered one of the best antennas for land mobile radio applications. BALUN of making which uses two cores, converts impedance into 1/4. Shop by category. This was an investigation into whether an inverted V dipole, notionally cut for 20m, could be fed offcenter to work on 20, 17, 15, 12, AND 10. BUILD THIS MULTIBAND FAN DIPOLE FOR ALL BAND HF ANTENNA EXCITEMENT Here is a fairly simple and easy to build multi band horizontal fan type dipole that can be constructed for all band operation from 160 meters up thru 6 meters or even higher. 6m from the edge of Element. Halfwave inverted V is: 34. Attempt #1 for an 80/40/20/10 didn't work as I can't actually fit the entire 40m odd long aerial on the property without bending the ends, and besides the wire snapped while I was trying to get it up somewhere so I gave up in frustration. I hung it in an Inverted V config with the apex hanging at approximately 70 feet and the long end (180ft) running to the south and the short end (90ft) running to the north. 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. Sign in | Report Abuse | Print Page | Powered By Google Sites. The quality workmanship is far superior than others. A simple multi-band dipole may be constructed by first choosing the lowest band on which operation is desired. For an 80-10 meter OCF dipole antenna, divide the ½ wavelength standard of 468 by the lowest operating frequency of 3. This particular version of the CW OCF dipole uses 300 ohm twin lead feedline terminated after 33 feet to a 4:1 balun. Wondering what the comparable performance would be. • Mount Vertical, Horizontal, as a Sloper, or as an Inverted -V – Try to get feed point ½ wavelength above ground if horizontal, sloper or inverted -V – ~35 ft on 20m, ~70 ft on 40m; V -Dipole should have end 4+ ft. Support my shows by using my new Amazon store. Also, designs that did better on 80 m, lack 15 m. Coax fed OCF 'Windom' antenna. Mine has a single fire feed like the old fashion Windom worked against some insulated radials, some ground rods, and the cold water pipe. I too use an OCF dipole with the top 1/2 wave long on 75m. The Moxon is up around 9 meters. I had a lot of fun, not only with QSO's and propagation, also with coaxial cable issue on 40m antenna. Thus, the off-center-fed dipole deserves an update. This pattern will reverse when the feed-point is moved as little as 5% off center. The hohpl--horizontally oriented and polarized loop 5. installed in MFJ-347 mount. This is a little page with lots of pretty pictures and graphs about my dual inverted V antenna for 40m. The balun is offset 3 feet from my tower at the 36 foot level. 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. If you found this video useful, please share using the Share button below. Amateur Radio Antenna Schematic Views. 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. Wanted to get something up in the air, in the clear, rotatable for 30 and 40. The 4:1 matches 50(75) ohm unbalanced coax to 200(300) ohm folded dipoles. Details Written by Rick-N8SDR Hits: 46109 Looking for some practical Multi-Band HF Backyard antennas?. It Will Handle The Legal Limit, 1500 Watts Of Power. You can build the antenna in inverted V but it will be less efficient and narrow bandwidth on lower bands. B uilt to last! Engineered to out preform! RadioWavz Wire antennas are the simplest practical antennas from a theoretical point of view; current amplitude on such an antenna decreases uniformly from the maximum at the center to zero at the ends. They also have an omnidirectional radiation pattern. into a small container equipped with a ring). A simple multi-band dipole may be constructed by first choosing the lowest band on which operation is desired. 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. In order to select the better. It's also ideal for those who want a high performance antenna with world class DX coverage 80, 40, 20, and 10 meters. The feeder length is about 35', and the top is inv-v style. Halfwave folded dipole is: 32. Yes, I have thought about it and may possibly do an inverted V at some point. When set up as an inverted-V the center of the dipole is lifted up and the wires of the dipole are sloping downwards. These are sometimes known as a Magnetic Longwire Balun. An important result from the isopropylidene series, was the isolation of an unprecedented adduct 101 derived from the reaction of the 1,3 dipole 96 (X is C=CMe2) with its fragmentation product, 8,8-dimethylisobenzofulvene (IBF) 100 (Scheme 15b). Dipole Cousins Inverted V – Only needs one support. 20m - Home-made SOTA Dipole (Pre-cut Inverted V configuration) 20m - 40m - Home-made Dipole (Ladder-fed Inverted V configuration, tuned with SGC-211 Autotuner) Yaesu ATAS-120A - mobile HF Screwdriver Antenna; Portable connectivity is via SSB Comms Aircell 7 or RG58U. This 40 and 80 meter inverted V antenna is made with loading coils. This antenna has resonant points within 160-80-40 meter bands at < 2:1 swr. 26 feet from one end. I recommend that you seal the end carefully. Separate the speaker wire into two 18-foot lengths. An Attic Coaxial-Cable Trap Dipole for 10, 15, 20, 30, 40, and 80 Meters John DeGood, NU3E [email protected] The larger the wire, the wider the bandwidth. Bob is the host of the popular Ham Radio broadcast, Ham Nation as seen on Twit TV and has featured and demonstrated this phased array system on two separate episodes. A 66 ft multiband Off-Center-Fed (OCF) style dipole antenna that covers the 40 thru 10 Meters Amateur Radio bands, most without an antenna tuner. A dipole antenna in free space exhibits a feed impedance of 72 Ohms, and has a doughnut-shaped radiation pattern. A sloping dipole with one end at the front third floor window and the other end at the edge of my front porch roof. Based out of Moscow Idaho we proudly serve the local community and regions EMS and Hams. Amateur Radio Antenna Schematic Views. At home I use a inverted V doublet. I think you would be better off using a center fed dipole in the inverted vee configuration(or dipoles) attached to a good current choke, and then fed with coax. See more ideas about Ham radio, Ham radio antenna and Ham. 45MHz) bands at my previous residence in Melbourne, Victoria in 2004 For my first HF antenna I selection a basic 40m band dipole primarily as a simple antenna that provided access to one the most versatile amateur HF bands. The maximum radiation for an inverted V-antenna is at its center. An Attic Coaxial-Cable Trap Dipole for 10, 15, 20, 30, 40, and 80 Meters John DeGood, NU3E [email protected] Horizontal is 90°. Dipole antenna basics Current & voltage Half wave dipole Folded dipole Short dipole Doublet Dipole length Dipole feeds Radiation pattern Build HF ham dipole Inverted V dipole FM dipole design The length of a dipole is the main consideration for determining its operating frequency. These Are A Very Efficient Multi Band Antenna. Dipole Cousins Inverted V - Only needs one support. This is a simple Two Wire OCF Dipole Antenna using a 6:1 Matching Transformer with a Coax Cable feed-in-line. Right: 3D far field pattern, with 2D elevation "slice" highlighted. KF9F Revives an OCF Dual Feed Multiband Dipole This multiband 160 thru 10 Meter antenna design was adapted using the dual feedline technique from and old 73 Magazine Article published in 1984 by W4HDX** Note that both ends of the feedline are tied together and only grounded at the tuner end. EAntenna - EA Antenna products from EAntenna online. To connect aluminum or steel wire to copper, make a couple of short #14 solid copper pigtails, twist them tightly into the aluminum or steel elements at the feedpoint, then solder an SO-239, or direct coax feed, to the copper tails. Steel whip on car 96 " or just a 40m ham stick. Dipole and Inverted V Antenna Basics (08 November 2018). Extended double Zepp is: 88. The maximum radiation from a dipole takes place in the centre. The SWR is better than 1:2. Overview - This is the 6-40 meter Alpha OCF Dipole Antenna. Over 12 years in the Army, current hobbies include HAM, firearms, and knife making. 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. fullwave dipole when driven at the center will display a typical ½ wave dipole pattern being directional broadside with null off the ends. I do not favor the G5RV and think the ZS6BKW is a better scheme. It shows an inverted V-antenna mounted on a roof top. A wire half-wave dipole trimmed for the frequency of use is very effective and also the most common type of antenna used for NVIS. 24 one side. Input Impedance of off center fed dipoles dipole or as an inverted V. Attempt #1 for an 80/40/20/10 didn't work as I can't actually fit the entire 40m odd long aerial on the property without bending the ends, and besides the wire snapped while I was trying to get it up somewhere so I gave up in frustration. Add your 50 Ohm coaxial feed line, suspension rope and go Can be hung Flat or inverted V configuration. The same is true of 10 meters; as frequency goes up, multibanding gets more quirky, and SWR curves and efficiency suffer. Overall length is 40 ft. ages ago n9ysq says: homebrew 20 m ground plane at home worked Spain first thing. A typical horizonal dipole for 40 meters would look like this;. 17 meter center frequency to ensure a low SWR across the entire phone band. The BuckMaster uses my flagpole as the top of the V, approximately 10 meters in the air, the ends of the V are around 8 meters in the air. A large size BBTD Inverted V Pyramid configuration is modeled in 4NEC2. Thanks to ladder line, the vast majority of my output power is now radiated at the antenna-- not lost in the feed line. The OCF-2K75S is only 79 feet long rather than 133 feet on the OCF-3K80. The larger the wire, the wider the bandwidth. I did find I got a better match hanging it from the center of the dipole and left the balun hanging at the feed point, looks like an inverted V feed OC which it is. If you have a longer garden, you can move the pig-tail join further back the return wire. An awareness of these changes can help ease the task of setting up a dipole for communications. com Free Ham Radio Classified Ads from QTH. Enter the desired frequency and select the desired calculation from the drop box. Schematic, core winding layout, and enclosure drill locations. 468 ÷ freq (mHz) = Length (feet). MFJ-2982 Feather Lite HF Vertical Wire Antennas are 31 ft. This inverted V-antenna is easily installed on a non-conducting mast. IMHO if I was limited in antennas I would put up an 80 meter inverted V (1:1 balun) and use a OCF cut for 40 meters on the same mast (4:1 balun) in a inverted V configuration. There is a way to make a half-wave dipole and only cut it two times, initial cut and final tuned cut. In some embodiments each of Z and Z' are independently selected from dT and dTdT. I had a lot of fun, not only with QSO's and propagation, also with coaxial cable issue on 40m antenna. Please subscribe to my channel to get automatic notification of new videos. Hung in a slight inverted V configuration. The Frizel OCF Windom with added coil and 30 feet of wire works on 160 centered at 1. I have the radio, power supply, and antenna tuner (if required) mostly narrowed down but am uncertain about antennas. Very fun this year when both 10 and 15M was open. My CW was “OK” but I had to burnish the paddle contacts after just a few minutes of operation. 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. Order 7-Band 5,000 Watt OCF Dipole Antenna: $707 Special Price: $538 (5,000 watt models are special order only and are made on-demand, so will always take a couple weeks to ship. Equipment: Icom IC-7300, 100W, TH6DXX for upper three bands, One element delta loop for 40m, Inverted V dipole for 80m, Inverted L for 160m, Log N1MM + 73 ES GL DE Robi, S58Y. Simple baluns can be bought from antenna suppliers, or made. Bob is the host of the popular Ham Radio broadcast, Ham Nation as seen on Twit TV and has featured and demonstrated this phased array system on two separate episodes. Taking one vertical angle and frequency with another, the RadioWavz DX (OCF) Windom is Omni directional. The Moxon is up around 9 meters. I think you would be better off using a center fed dipole in the inverted vee configuration(or dipoles) attached to a good current choke, and then fed with coax. OCF Dipole 7 band 80 -6 Rick on 27th Mar 2018 You are not going to find a better antenna than this one. Sign in | Report Abuse | Print Page | Powered By Google Sites. The advantages to an inverted-V configuration of an OCF dipole are pretty much the same as making a standard dipole into an inverted V. An important result from the isopropylidene series, was the isolation of an unprecedented adduct 101 derived from the reaction of the 1,3 dipole 96 (X is C=CMe2) with its fragmentation product, 8,8-dimethylisobenzofulvene (IBF) 100 (Scheme 15b). The ultimate achievement, the status flag, the pinnacle of being a HAM is when you operate from your own tower. Each is constructed from High quality 300 ohm transmit ladder line NOT the flimsy TV wire that has been commonly used by others in the past. A vertical seemed the obvious answer, a naturally low-angle radiator. and QRP-versions of industrial QRO-transceivers like TS-130 V, FT-707S etc. I tried using it in a configuration where the apex was about 16 feet off the ground (which flies in the face of Buckmaster's recommendation of 32 feet minimum) and the long element ran out for about 45 feet and then bent at a right angle. A tuner is required for full 80 meter operation. W1/Chaplin, CT. It’s true, a full-sized, half-wave dipole for 160 meters is rather big - around 250 feet long. The feeder length is about 35', and the top is inv-v style. The RadioWavz DX (OCF) Windom is a off center fed (OCF) dipole antenna that exhibits outstanding performance on all bands. Features include: Heavy duty stainless 1/4 inch center threaded, cemented with lock nut eyebolt supports the off center enclosure for years of trouble free service. 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. Alpha Delta Model DX-OCF Off-Center-Fed (OCF) Dipole 300 Watt antenna (3000 watt Model DX-OCF-HP may vary slightly) Center height 32 feet, end height 8 feet Erected as an inverted "V". The OCF dipole can be put up in a straight horizontal configuration - some times called flat top, inverted ‘V’, or inverted ‘V’ with drooped ends to fit on the smallest of city lots. I have been having problems with a high noise floor for over 10 years, in fact it was why i gave up radio 5 years ago. The Maxcon (OCF) Off Center Fed Multi-Band Dipole antenna does work very well and the construction and materials are excellent. Feed point impedance is high and requires a 4-1 balun. Full 135 foot antenna. 102 feet long, shorter than 80 Meter dipole. When I arrived home this afternoon, knowing that I’d have enough daylight left to install the traps in my 80 meter V. I use 80m and 40m OCF dipoles often for field day and at the school club. An inverted V has reduced input impedance and is often a good match for 50 ohm cable. Either works. JK Antennas can meet your needs with a wide range of Ham Radio, Amateur Radio HF Antennas, including Monoband, Dualband, Tribander, Multiband, operating on frequencies from 6M to 80M. a simple dipole of ½ wave for the same bands and that have the Baluns to the same height. "Ultra-Lightweight" 40m OCFD Antenna. 7 to 1 across the entire 80 meter band. 2% for the longest side after determining the half wave length at the lowest operating frequency…. Holding true to the original Windom formulas, I used a ratio of 37. The 4-Band antennas are OCF (off-center-fed), with a 23 foot leg and a 45 foot leg, totaling 68 feet. The larger the wire, the wider the bandwidth. I recently got my ham license and want to set up my station.