75 80 Meter Dipole

We compared both S meter and audio tests with this station in Denmark. Designed with 6063 corrosion-resistant aluminum tubing and stainless steel hardware, this antenna is very durable and attractive. MFJ-1779A 265 foot 160 Meter Single Band Dipole Antennafrom Radioworld. The folded dipole needs a 4:1 balun to match coax, but is a good match for 300 ohm twin lead. Super-strong injection-molded center insulator with built-in SO-239 connector and hang hole. The W5GI Multi-band Mystery Antenna looks like a plain dipole (see figure1 and photo A below) and is very simple to build. The example A an- tenna operates on 20 and 75 meters. This system is generally good on 80, 40, 20, 15 and 12 meters. K3ZXL - 160 Meter Receiving Loop Project Dan Schaaf 20 January 2010 _____ For several years, I have been struggling with atmospheric noise on the 160 meter band. Dipole antennas plans is a curation of 156 resources about , Trapped Dipole Antenna for 20-30-40m, The Galaxy dipole, Feed line Dipole for 2 Meters, All Band Dipole, Practical Dipole Antenna. 00 is required. ) Buckmaster 7-Band OCF Dipole Antennas are 135 feet (41 meters) long and work on 80, 40, 20, 17, 12, 10, and 6 meters. Short 85 foot long dual band 80/40 Meter dipole. 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. The quality workmanship is far superior than others. 65 2 or 468 2 ft f MHz m f MHz A dipole cut for 20. I use a tuner in the shack to peak the receive with the folded dipole on 40, 60, 75/80, and 160. Perfect for building a dipole. <= Back to Dayton New Products Hy-Gain 80-6 Meter Patriot Vertical Antenna AV-680, $549. A folded dipole has a feed-point impedance of approximately 300-ohms rather than 70 or 72 ohms. 12 meters is like 1. The 80m/40m antenna is my own design. Add Review ×. RADIO WAVZ 75 M double bazooka quiet antenna, easy to deploy. This is the length of a standard dipole but instead of dividing the result in half, use a 36/64% offset to determine the feedpoint. VERTICAL DIPOLE Since I had purchased the Kenwood TS-590 transceiver a few months before I got my license, I needed an antenna (or antennas) right away for listening on the ham bands. It's a Spi-Ro LS-80K limited space 80-meter. Distance from center of antenna to the center of the coil in feet (Must be less than half the total antenna length given above). Test Results for the Sloper vs Inverted-V Dipole on 80/40 meters Slopers are generally known to be good low angle DX antennas, while the inverted-V dipole is generally known to respond to higher angle, regional type signals. You can't work 'em, if you can't hear 'em, Kemosabe. The 80 metre trap as a closer view. Vintage Prestolite 16 857 Mfj-2105 Starter Armature Nos Free Shipping. Radioteletype is used frequently on this band as well. The half-wave dipole is very simple to construct. I have a 160 - 80 - 40 meter dipole up right now using his traps and conventional measurements between the traps and it's working great. and moderate gain over the entire 75/80- meter band. It gave me 40, 20 and 15 with a push because although a 40 meter dipole should give you a resonant 15 meter antenna, in this case - with the coils for 40 - it mucked the maths up and caused the ATU some trouble. Mfj Mfj-260c Mfj-260c Dry 300 Model Enterprises Dummy Load. In actual practice, 75 may be used for regional contacts from about 5 PM to about 9 AM, and 40 meters will carry you through the day from 9 to 5. The original was for 160 meters and I cannot say a bad word about the antenna. The 12-meter traps look like open circuits at 12 meters, so the outer sections of the antenna are effectively disconnected making a resonant 12 meter dipole when operating on this band. Sometimes on 80 meters but there the 80 meters 2 * 20 meter dipole fed with open wire gave me more qso's. 16’ ¼ lambda 60 METERS = 62. 73, Scott WA6LIE. I chose 58' for Mid 80 Meter Operation. Its new innovation provides rope lay construction strength and high flexibility. Get it as soon as Thu, Sep 26. This 40 and 80 meter inverted V antenna is made with loading coils. 8 MHz called for a coil diameter of 30 in. The antennas found in the tables are the ones currenly used by people on EME. Each cage dipole is hand made with quality and care, using materials that will take the abuse of even the most harsh enviroment. Figure 1—Elevation pattern of a 75/80-meter dipole 120 feet above average ground broadside to the antenna. I have tried a lot of different antennas. A double Bazooka doesn't cut it. For years the handbook has shown the 130 foot center fed "doublet", using open wire line to be a recommended multiband antenna. In the general case, if you are trying to match 50 Ohms, would you be better off feeding a normal backyard dipole with 75 Ohm coax if you are willing to prune it to a specific length after the fact? Continue reading Series match for a half wave dipole. The half-wave dipole is very simple to construct. Shop our group of long antenna now. moved to VK1HW. I have been asked why I haven't installed this antenna at my QTH. The large diameter yields broadbanded coverage of the 80 Meter Band. 80-10 Meter W7FG True Ladder Line Open Wire Fed Dipole 125' Dipole 100' Feedline $138. The No-Tuner, All-HF-Band, Horizontal, Center-Fed Antenna is our old friend, the 80 meter halfwave dipole dressed up a bit. The Wire Size can range from 16 AWG to 12 AWG. 80-10 Meter W7FG True Ladder Line Open Wire Fed Dipole 125' Dipole 100' Feedline 600Ω Open Wire Ladder Line One Conductor from Balun or Tuner to Far End Insulator No Splices, Solder or Crimping to Fail Extremely. The leg crosses the 80/75-meter dipole (marked in red). When determining how long to make each leg of a Dipole antenna, dividing the frequency in MHz into 468 will give the overall length. The finished antenna easily fits into a 3-foot cube. NVIS Fan Dipole Tribander I would like to try this as a folded dipole at 20’, no tuner, raised ends. Generally, 45 degree inverted Vees are the best compromise. (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. 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. How well and antenna works is a difficult question to answer. - Portable Vertical Antenna for 75m and 40m makes up a compact 28 feet high antenna. 80 meter dipole. More support for the coil would obviously be required. out perform a dipole antenna. Again, to minimize skin effect loss, it is important to keep the 3 in. 3 shows the current distribution along a 135' wire at 80 meters and at 10 meters. 92m from feedpoint to trap, 7. End-fed horizontal wire, an EFHW, offers the. The formula for the length of a real world half-wavelength dipole antenna in feet (meters) is: [3] 142. The 80 meter band begins at 3. Working Subscribe Subscribed Unsubscribe 1. The Top five list contains a few antennas that if you have the room for them perform very well. Rappaport, N9NB • I had been using a single feed dual band dipole for 80/160 m at N9NB • 80 m dipole is. The performance of the inverted dipole is spread out, and less directional than the conventional horizonal dipole. I have worked DX on 80 meters with my 100 watts. This article describes the results of measurements on one form of broadband dipole, constructed in the thought of reducing load variations throughout the 75-meter 'phone band. Dipole or Vertical? Tom Thompson WØIVJ Note: This posting uses hyper links extensively. Let's look at losses in a low 80-meter. At the least, a dipole should clear any sur- rounding buildings, and other large obsta- cles, for good performance. 975 to adjust for the effect of antenna wire diameter on length which is applied to the free-space half-wavelength equation. 8-Band does 160, 75/80, 40, 20, 17, 12, 10 and 6 meters, tuner may be required for 160. WHY USE A FULL WAVE HORIZONTAL LOOP INSTEAD OF A DIPOLE ON 160, 80, 75, 60 and 40 METERS? (Rev 6/2017) A dipole antenna just will not work unless it is at a sufficient height. The measurements below are for building a simple Dipole Antenna. Only 4 left in stock - order soon. Ada banyak sekali jenis dan bentuk antena yang dapat dipakai, namun yang paling umum dan populer untuk antena radio pemancar AM 80 meter band adalah antena long wire, antena dipole, dan antena inverted V. Made with RG6. 000 Power Rating 2kw Antenna Lengths 10 Meters each leg 9 ft. New Carolina Windom shown cut for 40, 20, 15 and 10 meters. No-Trap 80 and 40 meter dipole or inverted-V. W1/Chaplin, CT. The 40 metre trap in clearer detail. 0 MHz, hopefully at a VSWR of 2:1 or less. The SWR measurement of the 80m dipole with 250 feet of 50 ohm coax (Black), The SWR simulation of the 80m dipole with “lossy” transmission line resonator and 75 ohm Q section (Red), The SWR measurement of the 80m dipole with “actual” transmission line resonator and 75 ohm Q section (Green). Being that I was building a 10 thru 80 antenna ( if you remember it was a 40) I had to. 2m long, 3m from trap to end, and the capacity loads have a radius of 0. In order to select the better. The basic formula for determining the length of a center fed, half-wave wire Dipole or Inverted Vee antenna is:. The quality workmanship is far superior than others. In the evening when most of us have time to relax and enjoy a little time on the radio, the higher frequency bands are either dead or very crowded. The 160-Meter Coil. 15 Meter band dipole antenna including 150 Watt 1:1 BalUn, DIY kit. Cebik, W4RNL. For 160 meters a full wave loop antenna resonant at 1. In many cases 80-meter efficiency of an 88 ft dipole, or 40-meter efficiency of a 44 ft dipole, can be 10% or less. 80 Meter Rotatable Dipole. Let's look at losses in a low 80-meter. HF Antennas Especially stealth models for Dipole. Model Dry 300 Enterprises Watts Dummy Load. Enter the desired frequency and select the desired calculation from the drop box. The difference between the new Carolina Windom and the original Windom antenna is that the original Windom is not a dipole. You will not cover the entire 75/80 meter band on a simple dipole and not need a tuner. Here is the SWR measured across the whole range from 80 - 15 meter The 80 Meter band is shown below scanning from 3. The two to three less S units of ground noise over the dipole is probably the best feature of a loop and makes a dipole vs delta gain debate not worth the effort. I have worked DX on 80 meters with my 100 watts. NewSuperAntenna is the Official Super Antenna Systems Corporation website. The fact that you are using radiators that are large make it a greater target for high winds, icing, and the like. i would like to have the antenna >work on 80 meters also. Using multiple dipoles with one feedline is a common practice among hams, but the fact still remains that, for 80-meter operation, it takes between 120 and 135 feet of wire to radiate effectively. Built for Ham Bands from 2 Meters thru 80 Meters. The RadioWavz DX (OCF) Windom is a off center fed (OCF) dipole antenna that exhibits outstanding performance on all bands. On 75 meters, it functions as an in- verted dipole cut for SSB operation. M = Signal wavelength (l) in meters. This consisted of connecting one leg of the dipole to the center conductor, and the other leg to the coax shield. ) Buckmaster 7-Band OCF Dipole Antennas are 135 feet (41 meters) long and work on 80, 40, 20, 17, 12, 10, and 6 meters. Description. 500 MHz (which they would in this case) you are transmitting out of band. You can't work 'em, if you can't hear 'em, Kemosabe. swf?1431098067. - Assembled in 20 minutes by two persons. HOME BREW 11 METER LOOP ANTENNA. 22 Different Wire Antennas. And that's all there is to it! This is a great first antenna! Your next step, after getting some air time, will be to insert some traps in that dipole so you can use it on 20-meters. Add Review ×. Each arm of each dipole is connected with the arms of the other dipoles in the same side. , about ¼ wavelength. A horizontal dipole or inverted-V dipole for 80 meters 35 - 70 feet high produces competitive results at 500 miles or more 100 feet or higher produces competitive results at 1000 miles or more A dipole 70 to 100 feet high is a very competitive single antenna A horizontal dipole and a small 2 element Yagi for 40 meters. The vertical section (the “feeders”, ladder line, window line, or twin lead for 80, 40 or 20) function as the principle radiator. On 17 meters the traps look inductive, effectively. I found the lengths he gave to need some adjusting. Tie your dipole feed lines together in the hamshack. 60 meter band is 5MHz is the International Ham Radio band. The four bands planned are 80 meters, 40 meters, 20 meters, and 10 meters. Dipole Antenna Calculator. 15 MHz traps 0. 5:1 for receiving purposes. Murray, KD1BL Author's Note: This article describes a 75/40 meter NVIS, but one could use the construction techniques to build just a 75 meter or a 40 meter version. Model Mfj-260c. The dimensions are not too critical, and if your real estate can’t accommodate a dipole of this length, then you can droop the last 3-4m at. If you need a Sinclair dipole antenna, we’re happy to help you find the one you need. In myletter I hadsaid that. The dipole antenna still remains the primal antenna. Because of the spreader arrangement there is no pulling stress on the 40 meter dipole, it simply hangs from the 80 meter dipole. 7 which is ok and 15. and moderate gain over the entire 75/80- meter band. Better SWR curve on 80 and maybe helps 40 too. It's a Spi-Ro LS-80K limited space 80-meter. - 20 Meters each leg 17 ft. The antenna is constructed much like an ordinary Dipole antenna but with 5/8 Wavelength Elements matched with an added Impedance Matching Section of balanced feed line. The rules call for an omnidirectional horizontally-polarized transmitting antenna at a height of two to three meters above ground level. > >A fan dipole with one. The 8 wire full wave cage dipole antenna exploits the principles of a large diameter radiating element giving a broader band width, in the order of 2:1 for transmission, and 2. 5 mhz x 1 = 3. 25 - Right Angle Marconi Antenna. However, we can reduce the space needed to a quarter wavelength if we decide to use an end fed antenna. It can also be used as a building block for future expansion to a 2 or 3 element beam antenna. Tags: morse code bandwidth 75/80 meters international arrl chapter 3 arrl module 3a. In order to select the better. How well and antenna works is a difficult question to answer. Using the popular trap-type antenna on 75-80 meters, the overall length usually exceeds 100 feet with an extremely narrow operating frequency range. Model Dry 300 Enterprises Watts Dummy Load. Since the current does not follow the dipole pattern, the charge density is also different from a dipole. Dipoles at the correct height are not only stealthy antennas, they work great! Here is a six minute video that details the dipole and loop antennas that netted us DXCC and WAS in 9 days with 100 watts! The antennas are a bit difficult to see in the video, but that underscores how stealthy they really are!. Generally, 45 degree inverted Vees are the best compromise. 80 meter dipole. - Assembled in 20 minutes by two persons. By varying the length of the 450 ohm ladder-line feeding the antenna, we can achieve an SWR of less than 2:1 on all frequencies on all HF bands with the exception of the lowest part of 80m. The WX was fairly good enough in early March and so I decided to give it a try. dB) below a half-wave 75-meter dipole (no wonder, since a 75-meter half wave dipole is 130 feet compared to the 16 feet of the two whips). A 40-meter NVIS Portable Dipole Concept: I constructed this 40-meter dipole to readily switch between wire elements and loaded hamstick elements. com FREE DELIVERY possible on eligible purchases. communication on 75 Meters was started with a dipole at approximately 30 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. Click & Collect. 75 shipping * 10 meter (10M) Half-Wave Amateur Ham Radio Dipole Antenna w/internal. If you want 75 Meter operation make it 57 ft long. However, coaxial cable is unbalanced! When feeding a balanced load, such as a dipole, with an unbalanced transmission line, the antenna will induce RF currents on the outer shield of the coax. High Performance 80 Meter Transmitting Antennas 65 foot vertical with 30-60 shallow buried 65 foot radials good performance if a high dipole isn't feasible High horizontally polarized dipole at least 70-100 feet high easily provides 6 dB of ground gain - for free! Horizontally polarized 2 or 3 element Yagi, 2 element quad. HF 160 +80 + 40 METER HAM for sale New and used once. 975 to adjust for the effect of antenna wire diameter on length which is applied to the free-space half-wavelength equation. The dipole is constructed using top quality, Poly-STEALTH 13 Breaking strength 370 lbs. i would like to know what i would use for. 647 MHz) renders the dipole resonant on the 80 (actually 75) meter band, while resistor R has as sole function bleeding off stat-ic charges, hence protecting capacitor C. The leg crosses the 80/75-meter dipole (marked in red). This works very well with #18 to #12 wire sizes. 80-meter digital 63’ 1 ½” Jumper 4’ 7 ½” A Multi-band Resonant NVIS Plug and Play Dipole for 20,20 digital, 40, 40 digital, 60 80 and 80 digital. Each arm of each dipole is connected with the arms of the other dipoles in the same side. Multiband dipole, coax fed, no tuner I would like to put up a dipole antenna for 80 and 40 meters, and a frequency near 4. Dipole or Vertical? Tom Thompson WØIVJ Note: This posting uses hyper links extensively. This formula takes into consideration the capacitive "end-effect" from insulators which shortens the physical length requirement for the equivalent electrical length. Hello, I want to put up a center fed dipole for 75 meters. Go to 40 meters and adjust the 40-meter coil for your desired 40-meter. Well, all I can report is what the SWR reads. Example 4nec2 files included for most antennas. This consisted of connecting one leg of the dipole to the center conductor, and the other leg to the coax shield. The rules call for an omnidirectional horizontally-polarized transmitting antenna at a height of two to three meters above ground level. Like the previous models, it covered the 80 through 10 meter amateur radio bands on Single Side Band or CW at 100 watts, and was one of the most popular of Heathkit's ham radio products. for 75/80 and 160 Meters. This is the answer for mobile/portable NVIS ops for RACES. Model Mfj-260c. Because my back yard is rather small, I haven't been able to erect a decent 80 meter dipole antenna. 75 Feet Long. Each band tunes independently of the others. My K9AY RX Antenna. Bandwidth: An inverted-V dipole antenna has a higher Q than a simple dipole so it tends to have a narrower bandwidth. In the handbook the specifications for this antenna indicated it would' work on all of the bands above 80 metres also, that is 40 - 30 - 20 -17 - 15 - 12 and 10 metres. There are numerous reasons why people shy away from trying to put up a good antenna for this band:. 1/4 Wave Dipole Antenna Test Results With the 20 meter dipole at a height of 24 feet, facing East and West from Northport, NY (altitude 187 feet), 5x9 reports were received from North Carolina, Georgia, Texas, and Pennsylvania. A Portable 75/40* Meter NVIS Antenna - with 3/2/'09 updates - by David B. An inverted V has reduced input impedance and is often a good match for 50 ohm cable. I made my calculations, cut my wire to length, etc. 16 feet over all. The OCF-2K75S works the same as our standard Off Center Fed Dipole the OFC- 3K80. To find the half wave, divide that number by two. Antennas at this frequency are large: A quarter-wave vertical, for example, is approximately 65 feet (20 meters) high. It will work 80-6 meters with the built in tuners found in most radios today. Measure out a 120 feet length of coax and cut,this will be the antenna. 80 Meter Rotatable Dipole. After researching the different methods of increasing the bandwidth of a dipole, I have decided to try a Fan Dipole to cover 3. for the 160 Meter Band. Turn your existing 80-meter dipole into a broadband antenna by simply modifying the feed line. A Stealthy Homebrew Vertical Dipole Using Mobile CB Antennas. To determine the approximate length in feet of a Full Wave Loop antenna use the formula 1005/Freq in Mhz = length in feet. For 160 meters a full wave loop antenna resonant at 1. The 75 meter dipole wire is clamped and the 40 meter dipole wire is 'wire wrapped' to it. The large diameter yields broadbanded coverage of the 80 Meter Band. Being that I was building a 10 thru 80 antenna ( if you remember it was a 40) I had to. 80 Meter Off Center Fed Dipole sometimes known as a Windom, if DX is your goal then RADIO WAVZ brings you new technology at an affordable price. The first is an 80m dipole kit with instructions to build a very rugged legal limit half wave dipole. These handle up to 250 Watts but if you run lower power, they are a great alternative, particularly if our ProComm versions happen to be out of stock. At exact resonance the impedance at the centre of a half-wave dipole is like a pure resistance. 15) gives a folded dipole with a length of 65. 80-meter digital 63’ 1 ½” Jumper 4’ 7 ½” A Multi-band Resonant NVIS Plug and Play Dipole for 20,20 digital, 40, 40 digital, 60 80 and 80 digital. I have less tha 1. Based on experiments my friend Jim, AC9EZ, did. The Zerofive multiband Flagpole vertical is what you need to get on the air. Others go mobile on VHF and HF. Typically, this is 40 meters in the daytime and 75/80 meters at night. I was reading about the stick dipole and it stated that the rg-58/u was probably the best for the 80 meter frequency as it had better resistance down there than the larger coax. - A standard / remote tuner at the feedpoint will ease construction and allow operation from 3. The OCF-2K75S is only 79 feet long rather than 133 feet on the OCF-3K80. The dipole antenna still remains the primal antenna. Focusing on 10 meter base on the internet. 24 - Tilted Folded Dipole Antenna. 160 meters may be used in the wee hours, if RF begins to break through the F2 on 75. After many requests, here is a complete unit offered for my customers. Twenty meters designates the length of the particular radio wave used to transmit and receive voice and Morse code. The circuit diagram shown in Figure illustrates the schematic for the 80/40 Meter Direct Conversion Receiver. >I have a 1/2 wave 160 meter dipole ove some trees in my back yard, the >antenna is approx 123 ft per side. - 80 Meters each leg 63 ft. Being that I was building a 10 thru 80 antenna ( if you remember it was a 40) I had to. More support for the coil would obviously be required. swf?1431098067. Super-strong injection-molded center insulator with built-in SO-239 connector and hang hole. 80/40 Meter Attic Antena I live in a tightly packed urban neighborhood without much room for antennas. 9MHz(1-CH) CD160-x, CD160L The CD160-Series is a super-compact type dipole antenna for 1. I got very good reports on both 75 and 40 despite noisy band conditions. The team simply wound the 10 meters of wire on to the fishing pole and hit the TUNE button on the rig to swallow up any mismatch. It is a full size antenna on 40 meters and a shortened 80 meter antenna. To determine the approximate length in feet of a Full Wave Loop antenna use the formula 1005/Freq in Mhz = length in feet. I like to use a home made current choke to keep RF from coming back on the feedline. This is the length of a standard dipole but instead of dividing the result in half, use a 36/64% offset to determine the feedpoint. However, I've read elsewhere that care must be taken when using baluns on certain types of di-poles (primarily off centered di-poles) when operating on the 2nd harmonic (eg. Most signals are about 2 to 3 S units above my W9INN 20-40-80 meter dipole and the clarity is very close to the same, this antenna replaced a very good G5RV 10/80 meter dipole, that worked good on 75 meters but was down about about 3 S units from my W9INN dipole" —KB6HRT. Both sides have the same dimensions. 80/75 meter Cage dipole - Ni4L ANTENNAS & ELECTRONICS LLC. The antenna works on the bands as advertised with low SWR. by Gene Preston, K5GP I read Rick Littlefield’s article in the June 2008 issue of QST on off center fed dipoles and was intrigued by the idea that the antenna could be extended to cover 80 meters. High Strength Aerial Wires are manufactured with high strength, high conductivity Bare Copper-Clad Steel (BCCS) and insulated with a high quality UV Resistant Polyethylene to provide you with one of the strongest and longest lasting antenna. Generally, 45 degree inverted Vees are the best compromise. Murray, KD1BL Author's Note: This article describes a 75/40 meter NVIS, but one could use the construction techniques to build just a 75 meter or a 40 meter version. design a 40m dipole and then load the dipole to make the antenna resonant on 80m. Better SWR curve on 80 and maybe helps 40 too. However, we can reduce the space needed to a quarter wavelength if we decide to use an end fed antenna. This consisted of connecting one leg of the dipole to the center conductor, and the other leg to the coax shield. It worked okay, but not great. 80 Meter Dipole SWR Plot (from model) 80 Meter Inverted Vee SWR Plot (from model) In order to achieve the largest possible bandwidth with the dipole, it is necessary to match it to a 75 Ohm transmission line. P olyethylene black jacketed FLEX-WEAVE TM, 168 copper strands for high abrasion/rodent resistance light weight making this a excellent choice for the 125. When I was a novice, (anyone been a ham long enough to remember the CW only novice class?) I could only operate on 80, 40, 15 and 10 meters. My TX Antennae. Example 4nec2 files included for most antennas. I built this antenna and quickly tried it out in February of 2013. 80/75 meter Cage dipole - Ni4L ANTENNAS & ELECTRONICS LLC. Handles 1500 Watts. - Uses elevated radials for higher gain. 80-10 Meter W7FG True Ladder Line Open Wire Fed Dipole 125' Dipole 100' Feedline $138. 20 meter delta strung off a top corner of the chimney. I am using 75 ohm because I had some. 5 to 6 dB improvement as measured on 40m by Rudy Severns N6LF. - Portable Vertical Antenna for 75m and 40m makes up a compact 28 feet high antenna. In practice this antenna aIso works satisfactorily down to the 75 ­ 90 meter tropical bands, but not as well as a dipole or delta loop designed for 75 or 90 meters. I put a 160m full-wave sky loop at about 75 feet and it works pretty good. The 12-meter traps look like open circuits at 12 meters, so the outer sections of the antenna are effectively disconnected making a resonant 12 meter dipole when operating on this band. The WX was fairly good enough in early March and so I decided to give it a try. them 75 Ohms and maybe, close to 60- 50-Ohms, see Figure 3B. Sometimes on 80 meters but there the 80 meters 2 * 20 meter dipole fed with open wire gave me more qso's. Dipole: 20 Meters to USA, 100 W. The 40 meter dipole was loaded with some coils so that I could fit it in the attic. The Top 5 Backyard Wire Antennas (in no order) by L. 160m dipole 160m dipole pattern The structure of the 160m dipole is very simple, 75 meters of wire with a feed point in the middle, 15 meters over ground. AI4JI's Off-Center Fed Dipole Antenna System This antenna has become quite popular, as the performance is exceptional across the Amateur HF bands. I built one and used it on the air (75 meters) for a few evenings. 75/ 80 METER HAM RADIO DIPOLE WIRE ANTENNA w/ UNADILLA W2AU BIG SIGNAL. The 15 meter band dipole antenna is symmetrical so that the noise level will in many cases be quieter compared to asymmetric antennas. Add Review ×. Antennas for 15 Meters Antenna: 15 meters, Range: 21 to 21. In many cases 80-meter efficiency of an 88 ft dipole, or 40-meter efficiency of a 44 ft dipole, can be 10% or less. us, especially on 40, 80 and 160 meters. (dipole), based on 95% of electrical wavelength, considering end effects. uk 01922 414796, for all your radio needs. A second 1/2 wave dipole was built and mounted at 8 feet off of the ground. The easiest way to connect your rig to your antennas is to use 50 ohm coax such as RG-8, RG213, RG-58, or my favorite, LMR-400. It's a dipole, fed 14% off center with a 4:1 voltage balun. 400 pF; effective capacitance ≈ 478 pF at 3. 10m -160m Multiband “Z” Antenna. In fact, a half-wave dipole will often outperform many compromise commercial multiband antennas. This was a surprise as the Rs of my 75 and 40 Meter sticks are usually around the expected 20 or so Ohms. On 75-meters, back in the days of 3830 and 3895 radio wars, there was always a definite advantage to stations using low dipole with good screens or counterpoises below the antenna. , about ¼ wavelength. The thicker a dipole wire is (relative to its length), the wider the bandwidth. 3 shows the current distribution along a 135' wire at 80 meters and at 10 meters. This article describes the results of measurements on one form of broadband dipole, constructed in the thought of reducing load variations throughout the 75-meter 'phone band. 135 feet (45+90) long. After all, a dipole is a dipole. this was a trick I first earned from W8PSX in Westlake Ohio , where Jim had a counterpoise system below his 160-meter dipole. The 40 metre trap in clearer detail. On 17 meters the traps look inductive, effectively. An 80 m center fed dipole will work 30 m and 17 m, and 12 m with a little assist from a tuner (odd numbered harmonics). 285 with less than 1. Go to 40 meters and adjust the 40-meter coil for your desired 40-meter. Place a 1:1 Balun on the Antenna end of the Feedline. For a while, I was blessed with living at a home where I could raise the parallel dipole about 70-75 feet and stretch out a full length 80 meter dipole. The original was for 160 meters and I cannot say a bad word about the antenna. Order 7-Band 100 Watt QRP (low power) OCF Dipole.