80m loading coil

  • It will work all of the 40 meter band plus a portion of the 80 and 160 meter bands. Loading Coil The 110µH loading coil is used on the version for 80m. 2,7 MHz. Subscribe to topic 19 Nov 2015 3:32 Using the squid pole on other bands: The radiating wire with centre coil is directly fed at its bottom end on all other bands via an ATU. 5 uH and 1. Find great deals on eBay for ham antenna loading coil. ) To calculate the length of a full-size dipole, use the Dipole Antenna Length Calculator . The new design concept has made it possible to produce the long awaited 80m traps. Also, coil placed at the based of the antenna may be more easily accessible. The part between the loading coils is 26. Oct 22, 2013 A loading coil for 80m. The wires of this cable are connected into a zigzag configuration, like I used for my Cobra dipole. We are going to use an 80 meter ½ wave dipole for this discussion. This 40 and 80 meter inverted V antenna is made with loading coils. All antennas are supplied with Tuning Aid FG-1. Here are the dimensions of the 80m loaded dipole. The final loading coil design was 15. If you listen to the DX activity on the Low bands, you'd be forgiven for thinking that you're wasting your time unless you have a 4 Square Array, 20 acres of Beverage antennae, a huge Amplifier, and a neck like an anvil. Spacing should not be too topband I thought about adding 80m. The loading coil is wound on an 18 cm section of 32 mm OD PVC. At 3 in. COIL LOADING Loading coils can be installed anywhere along each leg of the shortened dipole. The magic spot for my 80m vertical. Find helpful customer reviews and review ratings for C. I require a somewhat large reactance on the element to help load it on 160M, (40&80M) are working somewhat satisfactory now My tank coil for the 80m/60m/40m bands consists of a 1 1/2" diameter National XR-5 five prong coil form close wound with #22 enameled magnet wire (diameter of about 0. The 80m and 75 meter bands add-on coil for all Super Antenna MP1 series antennas. The actual pull-in current for a RB1 is about 50mA. This resource is listed under Antennas/80M, at Coil loaded dipole for 80 meters resource page via dxzone. Tune Around! SEARCH CQ-Calling All Hams! About Hamuniverse Antenna Design Antenna Safety! Ask Elmer About Batteries Code Practice Computer HelpThere was a problem adding this item to Cart. 95: MFJ-65: 20 METER HI-Q, MOBILE LOADING COIL: $59. 5 inch pipe (which has an outside diameter of 1 7/8 inches). The variable inductance loading-coil tuning uses a novel “fixed spring contact” arrangement with the coil/whip assembly moving past this, “as one”. • Whether or not a loading coil is used • The location of the loading coil if one is used • Q L of the loading coil • Conductor sizing and losses in conduc-tors Figure 2 — Feed point impedance at the base of an ideal vertical. As these antennas can cover multiple bands (such as 20m , 40m , 80m ) using one relatively simple design, these are popular for portable radio-amateur operations such as Field Day . 80/160 Antenna 44 foot vertical, 4 top loading guys, 20 feet each, downslope angle approx 30 degrees. Description. Below resonance, when the trap is acting as a loading coil, only the outer braid is active, pro- ducing a much smaller effective loading induc- tance than that normally encountered with other types of traps. Note The following antenna projects were gathered from the internet, therefore the author …NC-204D from 1946: National Company, Inc. The traps themselves will shorten the amount of wire necessary to achieve resonance at 160m, similarly to a loading coil. 4 MHZ, series cap for 80m operation, loading coil for 160m 80m Z11, 20 ohms ideal gnd, 160m Z11, 5 ohms ideal gnd Band switching at base of antenna. 2m. Please try again later. I think if you measured that wire segment below the segment with the coil in it, you'll find that it's for 40 meters. 3 MHz Vertical Antenna MA8040V is a compact self-supporting HF vertical that delivers excellent DX-hunting performance on 80 and 40 Meters. 00. NC-204D from 1946: National Company, Inc. Note that, because your 160m dipole has inductive loading (from the 80m traps alone, plus any additional loading you have to add), it will have less bandwidth than a full-size 160m dipole. Tin the coil at 6T and 10T above ground for the 80M and 160M Quantity / Selection: Unit Price (USD) 00218 SmallIR Vertical Antenna 20m-6m 20m-6m continuous coverage, 18 ft total length, 12 lb weight, 1 sq ft wind load; EIA-222C wind rating without guys;A shortened multi-band End-Fed Half Wave (EFHW) antenna for 80-10m Steve Nichols G0KYA A shortened multiband antenna, about 23m long, for 80m-10m that offers low SWR (1. Skin effect loss is much higher in a close-spaced coil. Loading coils make this a full size antenna on 40 meters and a shortened 80 meter antenna. Weight:360g / Max power rating:200W(SSB) WRC-03 40m band extension for the Region 1 and Region 2 compatible. diameter, #12 copper) in series with a 1000 pF vacuum variable tunes the vertical to resonance. 80m coverage $ 405. Antena Short Dipole Loading Coil Monoband 80m On This Board; You cannot create threads. Grey wire was used as this is virtually invisible from about 10m way. More designs can be found by Googling “80m loaded dipole. HOW WOULD YOU LIKE TO SHORTEN YOUR Loading coil to tune out the capacitive reactance Linear Loading Capacitive end loading Combining some of the above. May 22, 2016 · Efficient 80M loading of 9. Adjustable loading coil system, with 102' whip it will resonate from 80m-12m, with 42" whip it will resonate from 40m-10m, with a smaller whip it can tune from 20m-4m. My TX Antennae. The 1. 80M Trap - 160M Loading Coil . To this point is attached the trap / loading coil, together with another one foot stub that is used to adjust the 40m resonant point. an inverted v antenna for 40 80 with loading coils this antenna is a full size on 40 and a shortened 80 by kg0zz . Well, a pretty good start. Click the button below to add the L-3. It is a small CW Tesla coil that operates at the unusually high frequency of 4MHz. With the HF2V, simplified, the loading coil for 3. The clip connects the 80 meter end to the 160m section with the coil in line up on the roof. 5-7. 5 MHz by adding end loading coils. • Varied top and bottom loading to achieve best match to 50Ω –Less coil, longer bottom loading wires –More coil, shorter bottom loading wires • Design was tweaked for 3540 kHz • Measured resonance was 3510 kHz –Easily moved up by shortening bottom loading wires A shortened multi-band End-Fed Half Wave (EFHW) antenna for 80-10m The 80-10m EFHW This is a shortened multiband antenna, about 23m long, for 80m-10m that offers low SWR (1. 8 to 30 MHz. 53. 80m Base Loading Coil for BigIR Vertical . 240 showing the receiver with AGS style knobs, a Volume control, a single coil frequency graph, no S-meter switch and many other differences from the actual production HRO receiver. The SteppIR 80m Loading Coil: The SteppIR 80m coil is designed to mount on the base of the SteppIR BigIR vertical an-tenna. (center). MMANA modelling shows a radiation resistance of about 5 ohms which makes the 9m long squid pole a very much more efficient antenna than a typical short HF whip. Basically, the loading coil is operating as a trap. Quantity / Selection: Unit Price (USD) 01811 80m Dipole for DB36 The 80m dipole option is a wire dipole that runs above and parallel to the boom, connects to the reflector element center on one side of the dipole and to the director 2 on the othert; The dipole is only -. 1. Discover ideas about Ham Radio How to make a ham radio coil-loaded meter inverted V dipole hf wire antenna. Jay in the Mojave Active Member. All information, images, and documents on this website are the sole property of MFJ Enterprises, Inc. 8mhz) is about 38. I already had the coil from another project, and this seemed like a good use for it. 4:1, but when power is applied, the SWR jumps high, even with even a low amount of power. DIPOLE Mono dan Dual Band 80m/40m Homebrew 1. The classic is back with improved design including three separate Hy-Q traps for 10 through 40m and a loading coil and an effective radiator for 80m. 8 or 3. 5m pig-tail for a total of 31. Smaller Coil is a Shunt to get minimum SWR, Larger Coil is for base loading for 160 Operation A Few perceptive designers realized quickly that coil Q was extremely important, particularly at 40M and 80M! 160M is another story for another time. ” Working 160M From a Small Lot designed for 80M, adding just enough coil at the base that his K2 auto tuner • Add loading coil at base if needed to Coil-loaded 40/80 Meter Inverted V Dipole Antenna This 40 and 80 meter inverted V antenna is made with loading coils. 50mm PVC storm water pipe also forms the top loading coil and double duty as insulator for the top hat. . 75 inches in diameter. For fine tuning, you need to insert a "variable inductor" or a variometer between the antenna wire and loading coil. 418' x 75' x 28' DRY BULK BARGE (Ref#1825) Built 1986, draft 19’6-3/8”, single hold, double hull, ABS class +A1 Barge, US Flag, 8019 GT, 8019 NT, hatch openings 302’ x 45’, hatch cover: 14 panels, 16 tons each, Marine Travelift 360D hatch crane, 525,143 cubic foot capacity, 12,779 LT deadweight, 2,687. Amplifier 80m Toroid: When first built, the amplifier only operated on the 40m, 30m, and 20m bands. 3:1) on 80m and 40m, and below 3:1 on 20, 15 and 10m. photo above: Artwork for the HRO Prototype published in National Bulletin No. inbox As the days grow shorter with the approach of winter and activity shifts towards longer wavelengths, I took stock of A successful morning today to convert my 40m vertical to an 80m vertical by adding a loading coil that I can switch out manually by just unplugging it. The MK-80 is an 80 Meter Add-On kit for the AV-14AVQ. - NC-240D (aka: NC-2-40DT or DR) National's "Moving Coil" receivers utilized a cast-metal catacomb that carried the various front-end coils and placed them into contact with the tuning condenser by way of small contact pins and pin-receiving contacts. Contact one of your local Diamond ® Dealers for current price & availability. 59 metres). This would require an Reduced efficiency would be with physically shortened element having loading element (coil, stub) exhibiting the current drop along its length and causing the distorted cosine curve, with less area underneath it. Adding the 80m loading coils and pigtails will increase the overall length of the antenna to 26m. The idea was to use a set of loading coils in series at the feed point create a good match in all segments of the 80m band. The RF is tapped onto the matching coil which is grounded at the base to inductively load the antenna at the proper impedance. 95: MFJ-67: 40 METER HI-Q, MOBILE LOADING COIL: $69. 80 Meter Coil Kit Assembly Parts: PVC coil form, light gray (1) Set up the PAC-12 antenna with radials and the 80M coil in place and check the SWR using a bridge or analyzer. With option UM-2 or TM-1 the antenna has a PL connector. for over 50 years. 9 MHz with a 730 volt supply drawing about 55 mA and a good 80 watts output with 1300 V and a little over 100 mA. 3-conductor wire in "Cobra" configuration Again, this antenna is base-loaded. The circuit I've used for this is identical to that of the 812 Hartley shown further down the page. Description. Tried tuning 80m, but even with the full loading coil I could only get down to around to about 4. ” Required loading-coil inductance as function of coil placement Base-loading (i. I don't have space on the roof for a full-size 20 metre length of wire. Material specifications AlMgSi tubing, diameter 55mm, length 2. The coil is so lossy (due The 40/80/160 Meter Coil-loaded Inverted V Dipole Antenna This coil-loaded inverted V dipole antenna is a resonate antenna that does not require the use of an antenna tuner. It works!. Loading coil calculated inductance µH The calculation refers to either a loaded 1/4 wave (typically a vertical, in which case flip the picture below through 90 o ) or a loaded dipole, in which case the dimensions refer refer to one arm and two coils will be required. This antenna works very well for DX on 80m. ceramic transmitting doorknobs expect some temp drift but not majorly objectionable. long, about the size of a 40m dipole. T his program calculates the base feed-point impedance and the loading inductance or capacitance required for resonance for a given vertical antenna height, diameter and operating frequency. mm. The loading coil has 9. the antenna elements to the balun, and a 5-turn hairpin match coil is placed across the antenna elements. The illustrations below show the behaviors of three antennas on 80m: To the left one with loading coil, in the middle the multi-resonant mobile antenna, to the right a trap-antenna . 5MHz. This page documents the design, build and testing of a 500W demonstration unit. The high-Q design and low-loss dielectric material combine to create a high-performance yet extremely durable coil designed The standard antenna covers 40m through 6m and with the exception of the mount and counterpoise, the loading coil, whip sections and 8 inch mast (mobile requires a 24 inch mast and fixed whip) all fit inside the loading coil which in turn fits inside the frequency tuning tube. MFJ-63, LOADING COIL, 40/80M FOR 1644, $39. At a length of 26m the antenna should fit into a small suburban block. It does this by adding a multi-tapped, high Q, base loading coil and a rotary selector switch that is controlled by the SteppIR controller. The air-gap Variometer . To the left is the 3/8-24 mounting bolt. Read honest and unbiased product reviews from our users. Cushcraft Low Frequency Verticals MA8040V 3. Any reuse or 06021 80m Base Loading Coil for BigIR Vertical Attaches to base of the BigIR vertical, expanding coverage to 80m and 60m bands; Additional 4 wire cable required when adding this option; 4 lbs weight; Power limit for 80m and 60m 1. The coil core is slid all the way down on the fishing pole, until it rests on the end stop of the pole. C1 selects the fixed variable capacitor for 160 meters and C2 selects the fixed capacitor for 80 meters. It’s a great HF antenna for the ham radio operator with a smaller backyard! The 80 meter with series coil. 05 inches). 80m short mid-loaded verticals So, as the loading coil is placed farther away from the feedpoint, a larger inductance is required. If speed of relay closure is not a factor, as in this application, a lower actuating current may be used. The whole coil (107 turns) is used on 80m. 5 TPI ( 3. Spread the 5-turn hairpin coil to ¼ inch spacing (coil to coil) or until a satisfactory SWR is obtained. It may be installed on a short mast driven into the ground or it can be roof mounted with the addition of the AV-14RMQ kit. To strip enameled wire, burn it with a lighter or torch and then use 150 grit sandpaper to remove the ash down to the bare copper. You will also need some 18 gauge magnet wire (available on the internet in one pound spools) and some number six stainless steel hardware. Prior to designing this coil, I considered the option of erecting a new antenna to keep things simple. Impedance is not important. ) (Calculator opens in a separate page. Show latest replies on top. The performance is still good, so ideal if you have a small garden or want to try experimenting with bits of wire. The rated coil current for an RB1 is 100mA. 15 MHz traps 0. Eight feet of antenna wire is attached to the other end of the loading coil. There are 78 turns of magnet wire on each loading coil. Compared to that of a dipole, an 80m hamstick is deaf and has a very narrow bandwidth - less than 40 kHz. (2x33 FT) MID-LOADED DIPOLE. Have owned this SteppIr Big IR w/80M coil for four years without issue until now. However, tapping points must be formed at every other turn near one end of the coil, making the winding process a little more complicated. 3 MHz Vertical Antenna MA8040V is a compact self-supporting HF vertical that delivers excellent DX-hunting performance on 80 and 40 Meters. Loading coils make this a full size antenna on 40 meters and a shortened 80 My QTH is on a fairly small lot and I don't have room for a full size 80m dipole. inbox As the days grow shorter with the approach of winter and activity shifts towards longer wavelengths, I took stock of Inductive loading: placing a loading coil (inductance) somewhere between the feedpoint of the antenna and the tip of the radiator. 90 - Double-Delta Antenna 80m and 40m. Then tried it again and made the coil not that nice, layers over each other and bingo. 150 Watt power load. The specifications for the 80m mobile loading coil are: 2 inches in diameter (50. At the time of writing, 20 watts of RF has been obtained at 1. Placing a loading coil here, requires the smallest inductance. base coil required to resonate antenna ~ 77 uH base coil typical R ~ 20 ohms Loading Coils Loading Coils 80m dipole 40m dipole - • - HF Mobile Installation Tips Diamond ® Antennas are sold through authorized dealers. This resource is listed under Antennas/80M, at Coil-loaded 40/80 Meter Inverted V Dipole Antenna resource page via dxzone. for the loading coil, is roughly ½ Ohm. The total antenna mast ,loading coil and top hat can be lifted with one hand. A 10uH roller inductor is configured as an autotransformer for impedance matching, one end grounded, the other end connected to the vacuum variable, and the roller connected to the coax center conductor. The VSWR was tuned on 20m by adjusting the length of the 10. Once you are happy with the coil you may choose to crimp or solder the wires to lugs or leave as is. Silver Plated WQD is installed at no extra cost. 5 TPI to make tapping easier and to keep the losses down, 11 turns were sufficient. 3:1) on 80mCushcraft Low Frequency Verticals MA8040V 3. 92m from feedpoint to trap, 7. Insulated 14 gage house wire was used. The 32ft section itself is resonant on ~7Mhz, and the top loading coil and capacitance hat produce an additional resonance on 3. A few feet of wire is needed beyond the choke to bring it to resonance, but this wire can be dropped down vertically if need be. Given the troubles with the prior generation traps, I wanted to ensure that the new traps were indestructible. Without the center loading coil the antenna can be used on 2m and 70cm by adjusting the length of the telescope. Final lengths: The 80m length is 67ft. BY KD8OUT, Mike Kieffer. com. However it will get you on the air from This is a video I made for a friend, K4WDR, also in Georgia so he could see the benefit of the NCC-1 noise phasing system. The system is 50 ohm coax fed to the base of the coil, with the shield or braiding going to earth. An antenna tuner can of course be used to increase bandwidth. All else being equal, the coil losses will more than double, and therefore the input impedance will be close to 50 ohms (no matching needed). 6oz) respectively. I thought I would bite the bullet and took the wire and loading coil off and When it comes to designing a vertical with a loading coil the two major items for the shopping list are the metal tubing for the element and an appropriate former for the coil. After some final tweaking to adjust the number of turns to 80M Trap - 160M Loading Coil . Most of us humans think an element that long is difficult to build an rotate much less keep up in the air reliably even for a single winter. If you use a fixed cap value ei.      Here is an interesting side note. A design by VK3JEG is only 66-ft. : You cannot create polls. 2, S trap, Loading coil for MHz, Pipe No. Half-size G5RV Conversion for 80m Effect of the 80m loading coils on bandwidth and other bands The 79uH loading coil and extra wires are not without a down side. 5 MHz band is a band of radio frequencies allocated for amateur radio use, from 3. I intend to build a vertical out of metal tubing and have capacitive top loading The base insulator below is for a 43ft vertical that was mounted over a good ground system and fed with a good loading coil on 80-meters. The EZNEC program predicted that the capacitors would need to be 60 pF and 150 pF when used with the 55 uH coil shown in figure 4. 5 to 4. Another design by KB0ZZ is a little longer, but resonates on both 40m and 80m. Hello, I am interested in building a vertical antenna for HF. For 80M, I scaled the 40M design and tried it (the wire length was 12. This design may be combined with the shortened dipole by providing loading coil pairs for each individual band. Figure 3 — Equivalent circuit for Z in. Tapped 160m and 80m loading coil I followed Tony’s idea of using 40mm PVC to make the loading coil, but differed in the top hat arrangements and the matching coil. Adding a loading coil to a 40m Vertical for 80m operation A successful morning today to convert my 40m vertical to an 80m vertical by adding a loading coil that I can switch out manually by just unplugging it. However the use of the loading coil and hat produce a much narrower range of usable frequencies on 80m compared to 40m. NEW LITE TRAPS for 10m, 20m, 40m, 60m, & 80m. HF-SSTC stands for High Frequency Solid State Tesla Coil. Since the calculator requires a metric input, we will convert inches to millimeters by multiplying by 25. Parts List for Loading Coils -- All #6 Stainless Steel Hardware. 1MHz. The coil is made by wrapping #16 Nysol insulated wire in a tight spiral around a section of 3" white schedule 40 PVC pipe. steppir. So, as the loading coil is placed farther away from the feedpoint, a larger inductance is required. 4. 80/40m Trap Dipole Measurements of the dipole are: 9. I decided to work with the vertical radiating wire that was already in position, but to interpose a loading coil at the base. up). Collapse the whip sections until minimum SWR is achieved. Solder the bottom coil turn to the ground lug. The lightweight loading coil was wound on a 52mm diam Black Pepper Corn Spice Tub The coil’s Inductance is 118uH and requires 61 turns of close wound 0. 95 each. The first point of the coil is connected to the SO-239 ground and the last point of the coil is connected to the holding section made out of 35mm copper tube. 1oz), 51gm (1. The antenna is resonate on both bands and does not require an antenna tuner. The Square Section Top Band Loading Coil 160m Top Band End Fed Antenna -G3YEU Coil Details:- 5” (127mm) diameter using 16 SWG bare copper wire. 5 inch pipe (which has an outside diameter of 1 7/8 inches). This goal led to a project to create a matching system for the antenna. But then a loading coil inserted in the mast is even more difficult. Antennae for the Low Bands. The coils use movable tap clips to allow us to fine-tune the match once the system is installed with the antenna on our tower. A length of 10m is enough for emitter computed, and measured and over a 200pF condenser uncoupled the resonant frequency of 7 MHz, at the coil. 914mm in diameter. Figure 4. Quantity 80m short end-hat-loaded verticals as the loading coil is placed farther away from the feedpoint, a larger inductance is required. To get to 110µF I used 76 turns. It actually works very well on 80m and excellent (like a full-size dipole) on 40m. It states that "if a length of wire is wound into a spiral-shaped coil and excited by a radio frequency current connected to the innermost portion of the coil, it will then, and only then, exhibit RF characteristics that closely approximate those of a resonant linear wire of the same length. 5 TPI to make tapping easier and to keep the losses down, 11 turns were sufficient. 1 metres of wire. 9 MHz in Regions 1 and 3 respectively. This compensates for the Inductive loading: placing a loading coil (inductance) somewhere between the feedpoint of the antenna and the tip of the radiator. If you want to get lower on 75m or 80m you'll need a base loading coil, which you could opt for a mix 2 t-400 and wind up with ease. 86 - Fan-Dipole Antenna for 80m to 6m. To make it “bigger”, I added 4 x loading coils into each corner. This is the view with the base loading coil screwed onto the base in the previous photo. end of the coil assembly, insert the remaining 3” brass rod through two adjacent turns on this end of the coil, through the brass coupling, and through the coil turns. What I am using for LF antenna matching is a relatively small ferrite pot-core instead of big coupled air coils. Near the apex for 12m and then again for 80m. With the traps, the antenna is resonant at 24. Making a Remotely Switched Load Coil Now that you have built a flagpole antenna and the yard is filled with 32 buried radial wires to make a ground system you are ready for a tuner or better to make your own matching system. It comes with a hinged based, and is also walked up into position. My initial version used only 1 in. From Reg, G4FGQ Vertical Antenna Phasing Arrays - From Butternut Antennas Vertical Antennas & Ground Screens-- By N6RK VHF Antennas - Various -- From The ARRL W5QJR Antenna Via Antennex The picture to the right shows the lower coil which is for 80 meters, the upper is 40 meters. the S-match antenna tuner. Lower mast is 2’ long Stainless Steel, or the "R" Version is 2 foot long with a 2 inch diameter black aluminum mast. File the plastic support ends if the coil fits too tight, then hot-glue the coil in place (the bottom coil turn is soldered to the ground lug). The antenna design is actually quite simple, with coil forms made from PVC pipe and magnet wire wrapped in a close-wound inductor. 5m, 1 The 80 metre groundplane radial I made is shortened to about 10 metres long and I put a loading coil in it about 7 metres out toward the end. Hi-Impact Modified Polycarbonate coil housing Silver Plated # 12 propriety coil wire NEW disc with Silver Plated BRASS balls for precision tuning. Next enable 80 meter operation (apply +12 V to the relays assembly) and select the coil shorting point for your desired resonant frequency and the tap point for best SWR. AC6V's HOMEBREW ANTENNAS LINKS INCLUDING ANTENNA THEORY . An extra coil is available as an accessory to allow 80m to be covered, as is a tripod stand for the antenna. To 80m, the traps look like high impedances, effectively disconnecting the extra wire for 160m. The required reactance that i need and theHomemade HF loading coil for short antennas. This will allow adjusting the coil without unsoldering. Finally remove the test clips leads, attach the coil clips, and sol-der wires between the coil clips and relay. 5MHz by using the 80m coil (minus secondary) as a simple base loading coil, then you can wind on the secondary. Product ID, Product Description, Retail Price. A loading coil for 80m. This is the most time consuming step. An 80 meter dipole (3. (Figure-5) ②Set grip nut rightly to treaded part of each radial element trap coil assembly. com ham radio guide 80m Loading Coil Example Let's assume the following loading coil with dimensions given in inches. cy and bandwidth on 80m by shortening the vertical radiator and increasing loading while lowering radiation resist-ance. Two sets of contacts are used, one for 10/12m and one for 15m to 80m. Overall the wire section above the loading coil is about 18m long (as long as I could get away with in free space). 4, No. element trap coil assembly by referring to the typical element length listed in Table A/B and fasten it with element fastener ring. The insulator failed at 700-1000 watts peak transmitter power. About; Jobs; Blog; Developers; Guidelines; Report abuse; Help forum Introduction The DX Engineering Linear-Loaded Multi-Band Dipole (Patent Pending) is a 74 ft, lightweight yet rugged design that is usable with a tuner from 3. Traps are used on this driven element in 2 places. Attaches to base of the BigIR vertical, expanding coverage to 80m and 60m bands; Additional 4 wire cable required when adding this option; 4 lbs LOADING COIL, 40/80M FOR 1644 . After some final tweaking to adjust the number of turns toOct 28, 2008 · Coil loading of an 80m dipole for restricted space #12 Moleculo, Oct 27, 2008. Finally the described antenna behaves as an antenna with loading coil, though of course with several resonance points. The stock one is very narrow band due to its reduced size. The further out on the leg the coil goes, you a higher radiation resistance (good), but requires a larger coil and higher resistive loss (bad). There's a hidden factor at work here too. 06025 80m/40m/30m Base Loading Coil for SmallIR Vertical 80/40/30m coil for SmallIR Mark III vertical antenna; Allows full coverage on the 80m, 40m and 30m bands; Power output limited to 500 watts on 80m, 40m and 30m, all other SmallIR bands are rated to 3KW continuous; Coil will only work on Mark III vertical; When it comes to designing a vertical with a loading coil the two major items for the shopping list are the metal tubing for the element and an appropriate former for the coil. Wound at 3. The MP-1 is a universal antenna with 180cm length and max. But performance is down about 8-12db on a dipole on 80m. My 80m loop was (and still is) square at about 15m per side which is actually too small for the 80m band. A low-loss 25 turn loading coil with a 5 turn secondary winding provides a near 50 ohm feed point on 80m. amateurradio) submitted 4 years ago by KG7IHV new: There's got to be a tradeoff when you use an loading coil on a short antenna, but I'm not understanding what that tradeoff is. Any reuse or redistribution of the contents of this website are strictly forbidden without authorization from MFJ Enterprises, Inc. Support the smaller coil on #6 nylon screws/nuts and #6 solder lugs as shown in Figure 6. I propped up the 4BTV section of the Hustler vertical on my porch and built a bracket to hold the new trap. Joined: Apr 6, 2005 Messages: 309 That coil is a loading coil for 80 meters, has nothing to do with the 40 meter antenna which is located below the 80 meter antenna. SteppIR Antennas - 80m Loading Coil Kit Drawing 1 SteppIR Antennas - 80m Loading Coil Kit 17 www. Antena Dipole Loading Coil Monoband 80m. 240 was published in the October 1934 issue of QST: HRO Design. DK5PT's compact ferrite loading coil for LW antennas. If we decided to pump 1500 watts into this system, approximately 150 watts will be dissipated in the loading coil. This compensates for the How to make a ham radio coil-loaded 40/80 meter inverted V dipole hf wire antenna. The loading coils of a short dipole must therefore be positioned away from the ends but still be closer to the ends than to the center feed point. The Basic G7FEK Antenna Twin feeder or ladder line. Produced to satisfy the requirement for lighter weight traps. A. This compensates for the Feb 19, 2017 K7MEM has a loaded dipole calculator that lets you play with different parameters to determine how big the loading coils should be and how far How to make a ham radio coil-loaded 40/80 meter inverted V dipole hf wire antenna. Taken on September 29, 2009 Some rights reserved. 80-160 antenna for the small garden. 80m capability was added to the amplifier in 2013 by adding a toroidal inductor (L1) in series with the original tank coil. The bottom section of aluminum tubing is 6 feet and the first upper section is a 11 foot section of 1 inch tubing being supported with a 1/2 of pvc tubing in the center that is lock in place with two brass screw if you look closely. 160m Capacitance Loaded Vertical Antenna. 87 - Capacity Tuned Folded Loop Antenna for 20m. All information, images, and documents on this website are the sole property of Hygain Any reuse or redistribution of the contents of this website are strictly forbidden without authorization from Hygainautomatic antenna tuners - concepts and tests automatische antennentuner - konzepte und tests automatiska antennkopplare - koncepter och testerThe AV-18HT features automatic band selection achieved through a unique stub decoupling system which effectively isolates various sections of the antenna so that an electrical 1/4 wavelength (or odd multiple of a 1/4 wavelength) exists on all bands. The way to get a perfect 50 ohm match is by trial and error, as described on 20m above. Designed as part of the /backpack /base /travel /mobile /portable antenna system for transmitting and receiving on HF and HAM radio frequencies. The 40M coils use 3/4 inch pipe (which has an OD of 1. Also, an optional base load coil option is available to extend band coverage to 60 and 80 meters. Also the bottom part of 80M band antenna is used for the upper bands antenna matching. Radials The loading coil of the MP-1 is quite a large diameter - much larger than those found in other portable whips such as the Mizuho ATX . and better than I thought it would! The loading coil is pictured above up on the roof. Quantity / Selection: Unit Price (USD) 00218 SmallIR Vertical Antenna 20m-6m 20m-6m continuous coverage, 18 ft total length, 12 lb weight, 1 sq ft wind load; EIA-222C wind rating without guys;A shortened multi-band End-Fed Half Wave (EFHW) antenna for 80-10m Steve Nichols G0KYA A shortened multiband antenna, about 23m long, for 80m-10m that offers low SWR (1. The 20m coil: Primary 10 turns enamelled copper wire, secondary 2 turns of hookup wire Cut a 70mm length of 42mm diameter PVC pipe for the 80m coil former. 5foot whip. 0:1 bandwidth was 10 kHz while at 1. up with loading coils to artificially lengthen the elements of previously assembled clone antennas. The loading coil fits over the fiberglass pole and is suspended in the middle of the 15′ radiating element. Next I’ll try it with only the 4’6” base section and see how it goes. The reason is, a 160 meter loading coil is about 5 times larger (in inductance) than an 80 meter loading coil. 5-7. The advantage of having a coil higher up on the vertical is clear: the higher up the loading coil is, the higher the radiation resistance. ③Connect vertical element parts (Pipe No. Radiation pattern at 80m In order to get an overall impression, you can see the plots for the 40, 30, 20 and 10m band, showing already obvious directional characteristics. 1/4” Diameter Support Fiberglass bicycle flags are readily available and inexpensive. 5:1 it was in excess of 65 kHz. 5 to 30 MHz continuous coverage and stainless hardware • Unique support line combats heavy ice loading • Black UV color ideal for concealment The Linear-Loaded Multi-Band Dipole kit includes multi-wire elements which are covered with an 80m dipole at 70 feet is about 1/4-wavelength above the ground. It comprises six sections each wound from 100g rolls of enamelled copper wire. 825 MHz. Using Bottom Loading • Bottom loading at the base works, but burns some power • Using bigger wire helps (#10 good) • In the recent Stew Perry, N6NUL worked JA with 100 watts using an inverted L only about 35 ft tall designed for 80M, adding just enough coil at the base that his K2 auto tuner could load it! (It helps that he’s near 80m loading coil (1/2) > >> Dear Friends I live in a city centre appartment, so HF antennas are a compromise as I only have my balcony on which to play. Ham Radio and Amateur Radio online equipment sales. The antenna has almost 300kHz bandwidth on 80m between 3:1 SWR points. 160m, 80m, 40m Curtain Zepp Antenna. In order for the "new" AGS replacement to meet the Quantity / Selection: Unit Price (USD) 00218 SmallIR Vertical Antenna 20m-6m 20m-6m continuous coverage, 18 ft total length, 12 lb weight, 1 sq ft wind load; EIA-222C wind rating without guys;A shortened multi-band End-Fed Half Wave (EFHW) antenna for 80-10m Steve Nichols G0KYA A shortened multiband antenna, about 23m long, for 80m-10m that offers low SWR (1. They ‘see’ 80M band antenna as a very large resistance because of large inductances of helix coil so the influence of one antenna on the other is insignificant. C3 selects the variable capacitor attached to the 12 volt DC motor. The horizontal wire is connected via a Plexiglas insulator with the rest of the wire of the former 160m antenna. This is the bottom of the 2 helical whips, a M40-1 and an M20-1 for 40 and 20 metres respectively: This view shows the inset 5/16" thread on the bottom of the whips: The helical whip simply screws onto the top of the in-line loading coil. 2m long, 3m from trap to end, and the capacity loads have a radius of 0. 5m at the ends. As the loading coil is placed farther away from the feedpoint, a larger inductance is required. 6 uh coil to resonate the shortened (41') radials (minimum power in a dummy load at 3. The 4 ft rod/cap hat combination is electrically longer than the usual 6 ft whip that one might use on a screwdriver antenna and therefore requires less of the screwdriver antenna’s base loading coil to be used to tune the antenna to resonance. 5 80 meter Loading Coil to your wish list. At the tip of the radiator, the current is zero. Included. Top loading with a capacitive hat is a good solution, maybe also in combination with a coil high up on the antenna. This is the LATEST innovation in HF mobile antennas! It is the PATENTED version of the standard Hi-Q Series of HF mobile and base antennas. I used 3. 5 ohms (3. I used standard 40mm PVC pipe from B&Q and 20SWG enamelled copper wire, which is 0. Vertical Antenna Loading Coils-- see LOADCOIL * Design short vertical antenna and loading coil. However, they don't shorten the 80m section of the antenna. Crane Twin Coil Ferrite AM Antenna at Amazon. 94 - Laid-Back Quad Antenna A half wave dipole on an 80m is about 130 feet or 40 meters long. → 4. 897. 99 Visit Fleetwood Digital for ~400+ #hamr #HamRadio related items! Buddipole Coil Set, These coils come standard with our Buddipole, Buddistick, and mini-Buddipole antennas. It appears to work very well, apparently giving some horizontal and vertical polarisation. Hustler Antenna. " On 80m I have now much less “loading” so I have around 120 kHz bandwidth on 80m (SWR better than 1:1. 8 mm), 100 Total Turns, 10 inches long (254 mm) In a base-loaded mobile antenna, there are three components that contribute to the 90 electrical degrees required for resonance. 540 and 1. These coils are 2 inch in diameter, 6 inches long and approximately 30 turns on each coil. 5oz), 72gm (2. The bottom of the loading coil is 3/8" stud mount. The forms for the loading coils are made of 1-1/2" (50 mm outside diameter) Schedule 40 PVC pipe. Tin the coil at 6T and 10T above ground for the 80M and 160M Another option is a shortened dipole using loading coils. 80m loading coil It is a full size antenna on 40 meters and a shortened 80 meter antenna. 1-1/4 When installing a loading coil of substantial inductance in an electrically short antenna, sheetmetal and dielectrics should be kept away from the coil and areas of antenna above the loading coil. on a coilform the resonance frequency was 4,5 MHz. Mounting hrdw. With the loading coil inserted in series with antenna wire, you will still be 100 Khz or more away from your desired resonance at 475 KHz. This For my 80M 4-sq with a Comtek box I use a 3. A 7 MHz dipole made to operate on 3. Vary the spacing on the two 7-turn loading coils to move the lowest SWR into the band center or area of interest. 0 MHz in IARU Region 2, and generally 3. The 80M coils use 1. com: 40/80/160M. For a first test I cut the inverted L in the middle for resonance on 80m. Attaches to base of the BigIR vertical, expanding coverage to 80m and 60m bands; Additional 4 wire cable required when adding this option; 4 lbs weight; Power limit for 80m and 60m 1. Figure 4 — Equivalent circuit for the input impedance with a The wire ends can then be screwed onto the loading coil. Also included were a 20ft (6m) control cable, a control switch, and a ferrite core. 91 - Inductance-Loaded Shortened Dipole for 160m. It is a full size antenna on 40 meters and a shortened 80 meter antenna. 76MHZ. Feb 19, 2017 K7MEM has a loaded dipole calculator that lets you play with different parameters to determine how big the loading coils should be and how far Here is a formula and calculator for creating a loaded (shortened) quarter wave vertical or balanced dipole. This antenna was first tested at a height of about 37' with good results. Inductive loading: placing a loading coil (inductance) somewhere between the feedpoint of the antenna and the tip of the radiator. 3feet)total length. For the desired frequency that I'm looking for, I know that a loading coil will have to be used in conjunction with the antenna, as the frequency will be quite low. 07mm stranded wire with an OD of 1mm. Bulletin No. Loading it as A Half Wave on 80M Coil Coil 70 ft 72ΩTwinlead Choke ANT TUNER Building Wire Antennas • Use Insulated House Wire (THHN) – #10 or #12 for heavy loads, long spans – #14 for lighter antennas – #18 or even #22 for stealth! • Use thimbles where wire bends to minimize stresses – • – Above the loading coil, the vertical section is suspended by Kevlar cord attached to a 2 x 2 inch post. The coil was held in place by drilling two holes in the former about 30mm apart and passing the antenna wire through them from the inside. Presently the coils are 2" OD open coils made with tinned #14 wire. The specifications for the 80m mobile The loading coil represents 3 Ohms of the total radiation and loss resistance of 28 Ohms. c. I require a somewhat large reactance on the element to help load it on 160M, (40&80M) are working somewhat satisfactory now with the design i am using. This antenna is an excellent performer, and ruggedly built. Lets see how the 40m part of the antenna would perform in a real installation. 5 turn per 25mm) Number of turns depends on the length of the antenna. The antenna has been tested well and it is best to use the recommended dimensions for all round multi-band performance. To get any signal out with a 9. The telescoping whip is less so. While it is not hard to raise it vertical, the weight of the top loading coil and top-hat causes the antenna to bend quite a bit as it rises majestically into the sky. On 40m the loading coil acts as a choke and isolates the extension wire. Since 40 and 80 is where I hangout these days due to the sunspot cycle , I replaced my fairly good performing 43’ non resonant vertical by DX engineering with the VA1 version of their 80m 1/4 wave vertical. 4 MHz to 60 MHz. L1 selects the 160 meter tap on the coil. If you can find thin fiberglass driveway markers or suitable fishing rod parts you might really be able to make a version of locally sourced parts. Here is a brief description of the parts: The winder and cover is for the T82-43 or T50-43 toroid for the impedance transformer. The Completed 80 meter coil Set up the PAC-12 antenna with radials and the 80M coil in place and check the SWR using a bridge or Coil loading of an 80m Dipole for restricted space By Chris Arthur VK3CAE Here's a method that may allow you to fit that 80m dipole into your suburban backyard Most suburban amateurs have quite a few constraints to deal with nowadays, one of the major ones is a lack of space. A 410 uH coil (6 in. The coil needs to be ≈1 uH, but the actual value may be between . The 160m length (physical length) 90 feet. Fabricating The Loading Coil. The Completed 80 meter coil Set up the PAC-12 antenna with radials and the 80M coil in place and check the SWR using a bridge or analyzer. The center loading coil is adjusted with a sliding tap, just move the outer part of the coil up and down. High-efficiency air-wound 80/40 Meter loading coil with 3/8x24 male and female connectors. The Q (inductive reactance divided by resistive losses) of an 80m hamstick is hilariously low due to the length and tiny gauge of wire used to make the coil. Everything In Place and Working !The Square Section Top Band Loading Coil 160m Top Band End Fed Antenna -G3YEU Coil Details:- 5” (127mm) diameter using 16 SWG bare copper wire. The stock 5BTV 80 Meter top loading coil is nearly identical to their mobile antenna top loading antenna. It is called the EFHW-8010. The coil itself is one previously used for 136kHz experiments and has a maximum inductance of 2140 uH. 5 Ft Whip. A physically small loading coil simply inserts a series inductive reactance that cancels capacitive antenna reactance. My thinking is that I can run the whip with a load coil and counterpoise similar to a mobile antenna or the mfj apartment A loading coil for 80m As the days grow shorter with the approach of winter and activity shifts towards longer wavelengths, I took stock of my log and noticed that while I have racked up a reasonable number of contacts on 15, 20 and 40 meters, 80 meters lags far behind. e. Loading coil detail The inductor was wound on a 22mm PVC former (a piece of 20mm pipe) with 17 turns of the antenna wire located 2m from the feedpoint. The 80 meter optional coil is also a clever way to extend the capability of this antenna to the lower bands albeit with compromised performance indicative of any “electrically short” radiator. An 80m Broadband Matching System. 70mA is appropriate. Probably the lightest traps on the market weighing just 40gm (1. 5 - A 475 kHz vertical with distributed loading inductor. Loading coil calculated inductance, µH Description. The antenna has a 3/8" thread bolt for mobile use, suitable for the appropiate base mounts. Attaches to base of the BigIR vertical, expanding coverage to 80m and 60m bands; Additional 4 wire cable required when adding this option; 4 lbs May 19, 2016 I do have a 9. I have an 80m hamstick, which is basically a 4' loading coil with a 4' whip on it. I modeled the antenna using 4nec2 to get the dimensions about right and the loading inductance needed for both 160m and 80m. turn spacing, and the loss was noticeable. DK5PT's compact ferrite loading coil for LW antennas. It works great for SSB operation on 75m but we have often wished we could use it across the entire 80m band. 2 Inductor location with top-loading Due to windage considerations mobile verticals seldom have much capacitive top-loading but fixed station antennas have (or should have!) as much top-loading as practical. 5" usable travel with approximately 350 uH inductance. A normal physically small (physically small compared to antenna length or wavelength) loading coil or loading inductor does not replace a missing fraction of a wavelength. The only problem that I'm encountering, besides lack of space, is that I do not know of any formula or calculator which can calculate the coil's specifications. Resonance is achieved by selecting the appropriate tap (in effect shorting out the lower portion of the loading coil) and then fine-tuning by extending or reducing the telescopic whip. Introduction The DX Engineering DXE-SWA-148 Linear-Loaded Multi-Band Dipole (Patent Pending) is a 148 ft, lightweight yet rugged design that is usable with a tuner from 1. 5 to 3. 2 mm holes are meant for RG174 coax and act as a strain relief, too. In addition I add a 4. I use an arrangment of double bananna plugs and jacks to facilitate band switching by patching the coil in and out of the feed. L2 the tap on the coil for 80 meters. it is negligible. The advantage of a choke trap is that it has no affect on the original antenna but when operated on 80m, the choke acts as a loading coil. Its BTV (vertical) antennas continue to set the standard for trapped vertical antennas, delivering the best reliability of any multi-band vertical on the market. 5 turn per 25mm) Number of turns depends on the length of the antenna. With switching it would be pretty easy, just short out the coil when you want to use 80m. The control cable connects to the bottom of the antenna and leads to the switch that controls the position of the coil (and hence the aerial's operating How to make a ham radio coil-loaded meter inverted V dipole hf wire antenna. bands in the same point. (The exact number of coil windings will obviously depend on the precise diameter of the coil former used). 92 - V-Beam Antenna for 15m. The box shown has been made a long time ago and was used for a remote tuner with many relays. 6 - Efficiency as a function of loading coil position. When coils are used in a dipole the coil Q is not much of a factor when related to efficiency. Center of antenna coil and capacitors (RG8x coax). Hustler Antennas has produced quality antennas and antenna accessories in the U. The coil contributes a certain number of degrees, 26. The loading coil at the top of the antenna is a piece of Close-up view of the matching coil. Smaller Coil is a Shunt to get minimum SWR, Larger Coil is for base loading for 160 Operation. A loading coil for 80m As the days grow shorter with the approach of winter and activity shifts towards longer wavelengths, I took stock of my log and noticed that while I have racked up a reasonable number of contacts on 15, 20 and 40 meters, 80 meters lags far behind. COIL, TAP AND SWITCH DETAIL. 5Mhz. 1, No. If you plan to put the telescoping whip to serious use, higher quality and longer replacements can be purchased from other vendors to improve performance. I am doing some design with vertical antennas for the low bands 40/80/160M. Shop with confidence. The standard version covers all bands from 7 to 30MHz, for 80m operations an optional extension coil is available. Because the coil needs to be about 46 uh, it is too long to fit all in one piece. Adding the 80m loading coils and pigtails will increase the overall length of the antenna to 26m. 5 turns, 6. The springs running towards the top of the picture apply tension to the insulators that are connected to the open wire feedline running back to the house and hamshack. Ouch to high by over 1 MHz. In order for the "new" AGS replacement to meet the ANTENNA TRAPS. Adjustable loading coil system, with 102′ whip it will resonate from 80m-12m, with 42″ whip it will resonate from 40m-10m, with a smaller whip it can tune from 20m-4m. For the loading and matching-section coil forms, I use 11/4-inch-diameter pipe so the antenna can be mounted reasonably close to the vehicle. Using an AIR core this coil shows a Q of over 1300 with a loss of only . This would include dielectrics on or near the inductor, since the presence …For some while, SteppIR has offered two vertical versions of this adjustable length antenna: one for 6-20 meters, the other 6-40 meters. 5mm hole near one end of the PVC and install a solder lug with 3mm bolt, nut and star washer. 80M Base Loading Coil for the BigIR Mark IV Vertical. Easy to install, and includes pre-wound loading coil and hardware. MFJ-65, 20 METER HI-Q, MOBILE LOADING COIL, $59. Includes One MFJ-347 & 2 MFJ-1640T Ham Stick Antennas. The previous article, Degrees of Antenna Occupied by a Loading Coil, showed how The Hamwaves Inductance Calculator can be used to determine the parameters of an 80m mobile loading coil. When measured, the resonant frequency was too low, and the match was not too good QUARTER WAVE 80 METER VERTICAL ANTENNA By W4NFR 2010. In my experience, it is always the coil former which causes the most problems. 2. So it is cut in two sections and mounted seperately. Where the last turn meets the plastic pipe drill a hole and feed the wire through the tube. 4 metre section. . A larger loading coil means more loss resistance and a narrower operating bandwidth. 4 degrees in the above example. If you wanted to include 40 and 80m then you would need thinner wire and a coil former, however efficiency of the antenna on those bands would be low, very low on 80m, thet's when you need to consider adding a capacitance hat, see the pic below for my cap hat: The loading coil will contain 5. 2 ea. The coil effectively stops the RF current flowing in the final 2m or so of wire at 7MHz and above. 5 ft whip on 80M you need to make the loading coil as high a Q as poslsible. Resonant at 3. My 80m loop is actually 60m all the way around. 1 x loading coil tube 2 x loading coil tube caps 2 x clips 1 x insulator (or 2 for inverted vee option). I had a few minutes today to set it up and try to get it tuned into 3. 95. Of course, an easier alternative approach might be simply to use an open wire feeder, and a tuner in the shack. Figure 4 shows the assembly. Issue is only on 80 meters: 80 meters will tune properly to its normal SWR, around 1. It will give the BigIR the capability to continuously tune from 3. 3, No. By putting the two sections in series, the inductances still add up. Drill a 3. 80m loading coilOct 22, 2013 A loading coil for 80m. The next step in my pursuit of 630 meter Shangri-la, also known as Nirvana, was to build a loading coil and variometer to match my existing low band antenna structure to the new band. 1uh coil to resonate the radials at 3. Existing loading coils for 80/40 are mounted at the 1m level, with a further insulator at that point. Solder the coil turns to the brass rod, and then solder the brass rod to the coupling. On 40m, because of the centre loading coil, the antenna is a full quarter wave resonant at about 7. The loading coil is constructed from 1/4 inch copper tubing, and supported by a structure made from PVC plumbing parts. (Calculator opens in a separate page. 5 uH depending on the actual input impedance of the antenna in question. I have multiple antennas but I cho The previous article, Degrees of Antenna Occupied by a Loading Coil, showed how The Hamwaves Inductance Calculator can be used to determine the parameters of an 80m mobile loading coil. Using a single feedpoint-located loading coil greatly helped the situation by reducing the required loading inductance, and reducing the impact of core losses on the feedpoint impedance – and also resulted in a simpler, cheaper, lighter, easier-to-construct antenna. HamCity has more than 30 years of experience in the amateur radio equipment business! Please visit us today for all your ham radio needs! The springs running to the left and right in the picture apply tension to the insulators that are attached to the North and South legs of the dipole antenna. vertical antenna loading coil vs toroid: vo1@gmail. The wire is cut so that 45 inches extend beyond the last hole in the ladder. Therefore, as you move the coil toward the end, there is a balancing of competing efficiencies. 740 and 1. The web site…A shortened multi-band End-Fed Half Wave (EFHW) antenna for 80-10m This antenna lets you get on to 80m in a horizontal distance of about 12m (40ft) when used as an inverted sloper with the apex at 8m, although you'll be down a couple of S points on a dipole. This is a shortened multiband antenna, about 23m long, for 80m-10m that offers low SWR (1. Attached to the bottom turn of the coil is a This coil-loaded inverted V dipole antenna is a resonate antenna that does not require the use of an antenna tuner. 027"). , at the base/bottom of the vertical radiator) is often easier to construct than off-base loading. : You cannot reply to threads. HF Antennae for 160m/80m Hi All, Over the last month or so I have been relegated to using a random length long wire for 80m and 160m operation and the offerings for such an antenna in a vertical flavour isn't all that good. 6 — The entire coil formed by the inner and outer conductors in series is contributing to the trap inductance at resonance. Visit. 2" diameter, 6" long using ¼" copper tubing. com Limited Warranty These products have a limited warranty against manufacturer's defects in materials or construction for two (2) years from date of sale. The 12m vertical and about 7 m long horizontal wire are forming the 80m radiator. The limitation for a given radiated power on 160 and 80 meters is normally going to be insulation somewhere in the system. 5 to 30 MHz. EZNEC derived inductance values were used to build loading coils using PVC pipe for the coil form. The higher up you put a coil the more inductance it will need to have and the more complicated the coil construction. It is simply a half wave end-fed on 80m which will resonate on all multiples of that frequency, loaded with a small inductance near the feed end. When choosing a mounting location, keep the following factors in mind: (1) Resonant frequency of HF antennas can change based on location. Fig. This is a little more than 10 percent of the total resistance. Red Cap Antenna RCYVU Dual Band VHF/UHF Amateur Ham Radio Yagi Antenna $119. 05 inches). Not using a rolling inductor this time but fixed taps on a loading coil and fixed (variable LOADING COIL, 40/80M FOR 1644: $39. Indeed, from 15m up to 80m , it is some 9’7” long. At the tip of the radiator, the Another option is a shortened dipole using loading coils. 2m and each loading coil has a 2. 95: MFJ-959C ANTENNA TUNER, SWL, WITH PREAMP EXPERT TIMES GRAPHIC ANALYZER $339. Adjustable loading coil system, with 102' whip it will resonate from 80m-12m, with 42" whip it will resonate from 40m-10m, with a smaller whip it can tune from 20m-4m. See more What others are saying "Then I took 4 pieces of the copper wire, which will be used for the antenna’s radials, and bent a little hook in one end, and then slid one screw in the hook of the wire then crimped down the wire around the screw as seen in …The clip connects the 80 meter end to the 160m section with the coil in line up on the roof. 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, to short six turns on this coil. Note that the accuracy of the inductance calculator is thought to be ± 10%. 5 TPI ( 3. 309 $, without Remote Tuner 199 $, GroundPlaine add on kit vertical antennas 6,7m (22") diameter 189 $; High Q add 80m loading coil for 33/43' vertical Antenna 149 $ Photos Back to content The use of a mid-point loading coil was investigated but it was not as effective as the top hat and would be quite unruly at the required 40+ uH for 80M While the SG-230 tuner is an ideal solution to tuning the antenna. Below the first turn and above the last turn drill a second hole and feed the bottom and top sections of wire out through the tube. The compact size offers many options on mounting location. The current-distribution tapers off, from maximum at the feedpoint to zero at the tip of the radiator element. 5 KW continuous, all other bands remain the same (3KW); * May require new firmware chip (sold separately) for non-SDA100 Controllers. Apr 07, 2009 · vertical antenna loading coil vs toroid Showing 1-31 of 31 messages. Both sides have the same dimensions. 88 - Indoor Loop Antenna for 80m to 30m. Use the Coil Inductance Calculator to design your loading coil. the coil without unsoldering. 5) and 200 kHz bandwidth with SWR better than 1:2. I could then use an alligator clip to short out turns for operation around 3750 KHz. This same coil design using a PVC form has a Q of only 250 with 3. This significantly improves the overall efficiency of the combination. It is 9" in diameter, 8" long, and has 17 turns. 93 - Picnic Vertical Wire Antenna. • No traps or coils • 3. For reliable operation and maximum coil life, a coil current of c. The antenna requires (2) 17 uH loading coils placed at the ends of the 10’ horizontal radiators. Tomorrow, I’ll extend the top whip to its full length and try again. 026" to 0. 7 dB below a full-sized dipole. EZNEC derived inductance values were used to build loading coils using PVC pipe for the coil form. The capacitors are lengths of RG8x coax. I think if you measured that wire segment below the segment with I came across the following antenna which covers the 80-10m bands with no traps and just one loading coil. The radiating element was initially a length of very thin (1mm), 7-strand Teflon-covered wire hanging from the top of the rod and plugged into the top of the loading coil. In order to give maximum efficiency the loading coil is usually mounted near the top of a vertical pole with a horizontal wire running from the coil. It has an easy changeable coil clip that allows for selecting a 40-50KHz portion of the upper and lower part of the 80m band or all of the 60m band. It won't be as efficient as a full sized 80m dipole and the bandwidth will be narrow. SO-239 female UHF Antenna Location & Mounting The CP6 is a compact vertical antenna using loading-coil radials. In loading coils, turn spacing is the biggest efficiency factor. For whips and verticals. The coil at left is 1 inch in diameter, has 9 turns, and wound with #14 Thermalese ® (enameled) wire. The 80m matching capacitor and and its coupling strap have been removed. The antenna consists of a matching coil at the base, a short mast up to a loading coil and the requisite whip or stinger at the top. 22 Different Wire Antennas. proceeded to install the center coil and capacitors. Mechanical details: The other 70 feet of wire acts as a loading wire and slope down from the top of the coil to near ground level. 0oz), and 90gm (2. 43 FOOT MULTIBAND VERTICAL HIGH Q ADD ON 80M LOADING COIL--NEW | ZEROFIVE-ANTENNAS . The original tank coil lacked sufficient inductance to tune the 80m band. 3- Screw the fiberglass loading coil and stainless steel whip assembly into one of the 3/8 X 24 connections on the MFJ-347. I can't give real numbers though. MDC40HX(7MHz/40m): Replacemant coil for MD200. The 80 meter or 3. I also put a homebrew 80m trap at the top of the vertical wire using a piece of Miniductor and doorknob (high voltage) capacitors. I installed a small loading coil made from B&W Miniductor at the bottom so that the wire resonated around 3550 KHz. 160m Inverted Delta Loop. Loading Coil Mounting and Taps The loading inductors are mounted using nylon hardware with the ends connected to the two antenna terminals on the sides of the enclosure. Exactly the same technique is used as for the 80m coil above. Build yourself a “postage stamp” 40 meter wire dipole antenna that fits in a space a little over 20’ wide and works reasonably well at low heights (20′). If, after tuning 10m and measuring results on all bands 40m is still "too low" in frequency, adjust the length of the uppermost tubing (between the 30m trap and the 80m loading coil) and make it shorter. This remains helpful for the 80M legs – we would need over 67 feet per leg otherwise, and although permanent installations are encouraged to do so, the 38 with coil option is easier and effective for portable use. Nice and Feb 5, 2018 80m loading coil I was thinking of adding a loading coil at the base/feedpoint, but I can't find You can make an adjustable coil at the bottom of the antenna. Not really knowing how much inductance to provide, my coil has about 80 turns with a tap every 10 turns. The specifications for the 80m mobile loading coil are: The method of “linear-loading” is a fancy way of saying “fold back on itself” – It reduces the overall length of an antenna without resorting to loading-coils. The loading devices are simple wire coils, which means no capacitors to burn out (or drift) like you have with a typical trap antenna. 8 MHz). 80m,40m,20m,15m,10m,6m,2m and 70cm eight-band vertical antenna (4 pages) Antenna Diamond Antenna W-8010 Operation Instructions Hf multi-band wire dipole antennas (4 pages) The build quality is great, particularly the loading coil and flexible whip. Last Updated: 01/02/2019 3:38 PM BARGES FOR SALE . Together these give a 99% efficiency. From readings at the other possible coil tap points my guess is that at this frequency range each face of the coil moves the resonant frequency by about 4 kHz. S. The whole thing was connected up and the shorter wire end connected to an 8m squid pole as a sloper antenna. 89 - Indoor Loop Antenna for 80m. for the 160 Meter Band. Verticals for 80m and 160m Loaded verticals for 160m and 80m have been popular for a number of years and are easily made. Traps are used on the driven element in 2 places. Use these inexpensive The tuning coil will be mounted at about the 6m level placing high voltage sections well above ground and away from building structures. A 10’ radiator is attached to the lower end of each loading coil. My K9AY RX Antenna. These coils are retained, in series with the main loading coil, but are relatively small (c 100uH). 80 and 160m. That coil is a loading coil for 80 meters, has nothing to do with the 40 meter antenna which is located below the 80 meter antenna. Close winding of coils should be avoided! The wire size (gauge) used for the coil is a factor. The base loading coil has taps for the principal amateur bands, 80m through 6m. com ham radio guide effectively as another loading coil. The center pin of the SO-239 connector is then connected to the motor control board which will turn the threaded rod to bring the loading coil sliding in or out of the copper tube. 5 which is the frequency for the Arkansas Razorback Net. 9 ST lightweight ship, 1346 gallon This 40 and 80 meter inverted V antenna is made with loading coils. loading coil section that was about 16" (-40cm) closed. The 3. 5 ohms of loss. The higher the bands the flatter becomes the radiation as well as the numbers of side lobes. 5 MHz on one is described approx. coil loading of an 80m dipole for restricted space here s a method that may allow you to fit that 80m dipole into your suburban backyard by vk3jeg . Homebrew Buddistick Project – Part 3 I have had a couple of comments regarding the 80m coil for the homebrew Buddistick. The number of coil turns and wire gauge are also calculated for a given coil length and diameter. 5 KW continuous, all other bands remain the same (3KW);Quantity / Selection: Unit Price (USD) 00218 SmallIR Vertical Antenna 20m-6m 20m-6m continuous coverage, 18 ft total length, 12 lb weight, 1 sq ft wind load; EIA-222C wind rating without guys;A shortened multi-band End-Fed Half Wave (EFHW) antenna for 80-10m Steve Nichols G0KYA A shortened multiband antenna, about 23m long, for 80m-10m that offers low SWR (1. 80 Meter Loading coil assemblyWhat's the downside of adding a loading coil? (self. The one on the right is 7 turns, and . 80m Base Loading Coil for BigIR Vertical; Back to topics. 5 meters (126. Coil-loaded 40/80 Meter Inverted V Dipole Antenna This 40 and 80 meter inverted V antenna is made with loading coils. At this point, you may prefer not to solder one end of the coil. 80m: Assuming you have achieved resonance at the target frequency of 3. 900, 3. Orb Thompson to coax by using loading coils • For best results, the coils are placed in the middle of each leg of the dipole • Loading coils can introduce additional loss of 1 dB or more • For dipoles longer than /3 the antenna can be matched to coax by using linear loading Hamsticks and their clones are for US 75m (4MHz) and not directly tunable to 80m (3,5 MHz) I plan a Hamstick dipole for Digimodes and CW for say 3560 kHz. It also acts as a loading coil on 80m