Base loaded vertical antenna. Homepage van Maarten Ouwehand PG1N.

Base loaded vertical antenna Performance and repeatability of results, based on number of QSO, makes this aerial a keeper. 68M driven element. The ARRL Antenna Book; Off-Center Loaded Dipole Antennas, QST magazine, September, 1974; Coil-Shortened Dipole Antenna Calculator The Single Element loaded vertical (left) has a loading coil inserted at the base of the antenna element. 30 kHz From the above, determine the antenna Q. Sometimes “short” is defined as a vertical with a physical height H<λ 0 /8 or 45˚. The loading coil is often placed at the base of the antenna, between it and the transmission line (base loading), but for more efficient radiation, it is sometimes inserted near the midpoint of the antenna element (center The 18 foot AV-18VS radiator has a loading coil at its base that allows precision antenna resonating. Coily, Monkey Made, Tram, K40, Wilson, Ranger and Browning. 6 Mhz which confused me. The antenna worked very well as I felt it. More of that later), the main experiment seems to have worked in giving me a vertical for 40 meters but I also discovered a resonance at 23. Is this just a counterpoise? Or is it something else? I found on Amazon. 1) or a shortened "Up & Outer" antenna (ref. 9 MHz. Putting up the antenna is simple: the top section is secured with a wing nut then the vertical is walked up hand-over-hand into the upright position and locked in place with the pin. Jan 9, 2011 · And, because of that, antenna analyzers are not always too useful on the low bands. Lima OH 45802, GOI-51048 telescoping whip antenna. You often read-/hear recommendations to use a centre, rather than a base-loaded whip for mobile HF. There are two currents, a radiating "antenna current" =2X(Ia/2) and a circulating "transmission line current" =I T. This antenna is designed for stations having a difficult time putting a decent signal on 160M from small or CC&R'd lots. The main thing I'm trying to sort out is the mention of a 5 foot ground lead. And, besides the super well-built and elegant AX-1, QRP Guys sells an interesting looking kit, and there are some good 3D printed designs I might want to try out. e. Center Loaded Vertical Antenna kit; QRPGuys EFHW Antenna 40m-15m or 80m with Tuner; QRPGuys DS1 40m -10m Antenna; QRPGuys 40m-10m UnUnTenna; QRPGuys 40m-10m UnUnTenna Plus; QRPGuys Portable Tri-Band Vertical Antenna 40/30/20m; QRPGuys No Tune End Fed Half Wave Antenna 80-10m; QRPGuys Wire Antenna Trap Kit; QRPGuys Multi-Band End Fed Mar 28, 2025 · The following description should give you guidance on how to build a mobile antenna for HF bands yourself, using a very cheap CB-mobile whip antenna base. 5 m aluminum tubing (7½ mm OD). For a 50ft vertical segment the impedance is about 15 ohms. So, knowing already that the antenna was near self-resonance after my K8GU/9 efforts, the first thing I did was just hook the antenna up to a TS-930 and give it a 5-10 watts fed against my nearby 80-meter vertical’s radial field. I am trying to understand how to electrically wire it though. First off is the base or antenna support. If you look over on Frank, G3YCC's homepage, he has some compact Base-Loaded antennas shown for mobile or portable operation. 2. A Linear Loaded Vertical Antenna ©1998. PVC sections bolted together, and 1/2 wavelength of antenna wire helically wound around the PVC sections. The rods themselves are 24 inches long made of aluminum with 3/8×24 threads with couplers and jam nuts on the end. 15, February, 1944. 1 / 4-λ vertical with short-ened, loaded radials over seawater the ground losses are very small, and even the losses due to base loading of a shortened vertical radiator are small. Short, unloaded vertical monopole 35VCxx(A). Center Loaded Vertical Antenna kit; QRPGuys EFHW Antenna 40m-15m or 80m with Tuner; QRPGuys DS1 40m -10m Antenna; QRPGuys 40m-10m UnUnTenna; QRPGuys 40m-10m UnUnTenna Plus; QRPGuys Portable Tri-Band Vertical Antenna 40/30/20m; QRPGuys No Tune End Fed Half Wave Antenna 80-10m; QRPGuys Wire Antenna Trap Kit; QRPGuys Multi-Band End Fed • Use NEC to model antenna and predict inductance required to resonate the the antenna – or: Use Vector Analyzer to measure feedpoint Z of an existing antenna that’s too short, export data to SimSmith and predict inductance • Coil winding formulas in ARRL Handbook are very accurate Jul 9, 2018 · Voila, a tri-band, base-loaded antenna. The VERT 160 BASE/TOP LOADED is a vertical antenna with a loading coil at the base and a capacitive hat on top for the 160 meter band (1. A variation on this technique is the "umbrella" vertical antenna. I changed the antenna configuration again - just for fun and out of curiosity. A linear loaded vertical antenna A loaded base-fed vertical by Ross Wilkinson G6GVI. Antenna Q = 360f. "Capacity" hat vertical monopole 35BLxxxx(A). The hat consists of a number of radial wires that slope away, downward from the top of the antenna. The 23rd Edition of ARRL Antenna Handbook has a brief listing of a base loaded vertical antenna on section 10. com a 20 ft. This is often the simplest and sturdiest situation, but it is also the least efficient. 4 to 0. Antenna 2 - The short base-loaded vertical. z. Antenna, Vertical, HF, Base Loaded, 1,500 W PEP, 80, 40, 20, 15, 10M, Band Changed Manually at Vertical Base Coil, 18 ft. Eureka St. 2mm m… A top loaded vertical antenna has several advantages over the conventional vertical, but the biggest advantage is that it's shorter in length. 4. The original javascript was created by Jack Ponton and can be seen here. Quarter Wave -vs- 5/8ths Wave Vertical; Quick SWR Calculator for Vertical and Dipole Ham Radio Antennas; TOKYO HY-POWER HL-700B 600 Watt Amplifier purchase; Adding 80m to DX Commander All Band Vertical (9-bands 80m through 6m) DX Commander Contest Antenna achieves top placed UK IOTA Station; Software Modelling your Vertical antenna ground 18 hours ago · Find HF Vertical Antennas and Packages and get Free Shipping on Most Orders Over $99 at DX Engineering! Antenna, Base Vertical, Multi-Band, 3. These data are listed in Fig 2 under Antenna 1. Base lumped-constant loaded antenna 35LLxxxx. I was thinking about the following method: It is based on the fact that the current distribution in the antenna is sinusoidal; it radiates more in the proximity to the balun and almost doesn't radiate at the end of the arm. At 1. Because of it’s superior build quality and reliability, The Ranger 80 is well suited for EmComm services and NGOs using the HF Mar 7, 2019 · The problem is I'm not a mathematician and don't know much about antenna theory. 00 price range, and it would lend itself to a portable base-loaded whip, or the top section of a Center-Loaded potable antenna. 2A/B/C). Sep 25, 2021 · 4 MTR (13 FT) VERTICAL MONOPOLE WITH SINGLE ELEVATED RADIAL. vertical antenna, made from three 10 ft. , at the base/bottom of the vertical radiator) is often easier to construct than off-base loading. The base of the vertical was 14 m away from the water, so some radials rested in the water. File name Antenna Type 35Vxx. It is a 25 ft. KL7JR on 2015-09-10 May 28, 2010 · Yesterday i went to a local ham fest and watched at a stand keeper that sold antenna feed lines, coax window line and antenna's selling the premade antenna's ( wire) at a fast pace. With center loading, the portion of the antenna below the coil carries high current, and in the top loaded version the entire vertical element carries high current. . I also included end-hat loading in my 8 mtr (26 ft) mid-loaded wire vertical. A folded monopole can be viewed as a superposition of a vertical and a transmission line shorted at the far end as shown in 4. Band The Shooter — A 3- Portable Antenna in a jiffy? Try Want a vertical you can put up or take down this penny-pincher's Field Day special! The 160 meter loaded vertical antenna is constructed using an inexpensive Telescopic Fiberglass Fishing Pole 10m in length. The coil diameters that will be used will vary from a minimum of 1" (25. For super portable I have a DIY version of the QRPGuys DS-1 (which I also have). Aug 14, 2024 · The Recon 40 is a fixed inductance coil system to turn a 17 foot whip, which is resonant on the 20 meter band, into a base loaded vertical antenna that is now resonant on the 40 meter band. Because of its build quality and reliability, the Ranger 80 is well suited for portable and EmComm operations. The Hy-Gain Model 18V-S is a trapless, vertical antenna which is manually tuned to any band, 10 thru 80 meters, by a simple adjustment of the feed point on the base inductor. Crappie Fishing pole that collapses down to just 4 feet. A lumped element equivalent circuit is shown where Ra+jXa represents the vertical and +jX T The basic antenna is a vertical monopole, using elevated radials to complete the “ground plane. Scott MacKenzie" <kb0fhp@> wrote: I am trying to figure out a design for a base loaded 160M vertical. 10-80 Meter Vertical Antenna. I have been operating from an apartment in Maracaibo, Venezuela for over a year and during that time have worked well over 100 countries, all 50 states on HF, and well over 100 grid squares on 6 meters mainly using CW, SSB and PSK31. The multi section element is Built from super strong T-832 Drawn aircraft aluminum. 160 meter linear loaded voltage feed T 160 meter linear loaded voltage fed T antenna Feb 23, 2024 · The REZ Antenna Ranger 80 HF is a base-loaded vertical designed for portability and rapid deployment. I wanted high efficiency 40 Meter antenna with low-angle radiation. For example, I've modeled my 160m inverted-L in different configurations and seen how the point of maximum current moves up and away from the base. The illustration also reflects the model used to test these antennas. The Ranger 80™ is a rugged, base loaded vertical, designed for portable, rapid deployment. (More on this antenna below). The AV-18VS may be installed on a short 1-5/8 inch diameter mast driven into the ground. Home-Base HF Vertical Antenna Nov 13, 2021 · Subject: Re: [MMANA-GAL] Shortened 160M Base Loaded Vertical Scott . Nov 2, 2015 · Stealthy 10 & 12 Meter Vertical Monopole Aerial Using CB Antennas Created by John Reisenauer, Jr. It is question- Oct 30, 2022 · There are a million variation on a small base-loaded vertical antenna, and you can definitely improve upon this design. Top linear-loaded antenna 35VTxxxx. It is also ideal for shortwave listening. One of my interests in Amateur Radio is operating with short inductive-capacitive top-loaded, ground-mounted vertical antennas on 160 meters. An antenna loading coil is an inductor placed in series with an antenna element in order to lower the antenna’s resonant frequency. Radio sales, P. The base tube is CNC machined from 2 1/2 inch 1/4 wall T-6 Extruded aluminum for maximum strength. 4 Measure the antenna length and calculate the antenna capacitance using 1. All those 10000 log contacts prove is that you can work a bunch of people running QRP power levels, which is what is radiated from that antenna with a 100w signal going into it. AV-18VS antenna pdf manual download. This is the body for a 3-band, base loaded ham radio antenna for 40, 30, and 20m. This shortened easy-to-build vertical, with no-radials, is made from surplus military camouflage poles. 7ft x 1. Because all forms of NEC have difficulties with very small angles between wires that join, a model was made of a set of parallel wires with cross wires. Open Box Hy-Gain AV-18VS 18' Base Loaded Vertical Antenna SN165263. You can find several commercial offerings ranging from mono-band to multi-band (6 to 160m Base-loading (i. The insulator was made from I-inch maple dowel, Antennas. 5 m (8 ft) radiator made of aluminum tubing, and one with a 6 m wire strung along a telescopic fishing pole. for 40M and 80M ©1998 David Reid PA3HBB / G0BZF. 2 AWG which is over 7mm instead of 1. ” (1999 CQ 160), and a base-loaded coil made from #10 gauge View and Download Hy-Gain AV-18VS instruction manual online. Without Radials . 16 λ 0) where λ 0 = free space wavelength. This system features an easy to deploy telescopic stainless-steel element, which can be retracted when winds in excess of 50 MPH are expected. Why is this? To what extent does centre-loading beat base- Hy-Gain AV-18VS - Antenna, Vertical, HF, Five-Band, Base Loaded, 1,500 W PEP, 80, 40, 20, 15, 10 meters, 18 ft. A coil placed at the based of the antenna may be more easily accessible. In fact, the performance amazed me, because the whip was mounted parallel to the 2m/70cm antenna, with only about 2 inches of separation, and the counterpoise wire was largely covered by the truck. Why not always use base-loading? This is primarily driven by coil losses, hence, efficiency of the antenna. A base-loaded vertical is shown at C. By adding the rods you move the coil up about four feet which is going to do a couple of things for you. Base hardware for the antennas being tested. Follow these guidelines for highest efficiency in coil-loaded antennas. 2 A base loaded vertical antenna for use on all the bands from 6 to 40 meters. Page 3 of 9 April 2017 W1DYJ ~ 40M Vertical Figure 4 - EZNEC comparison: elevated vertical (with 4 radials) vs. 20 MTR VERTICAL 3 MTR (10 FT) MONOPOLE WITH SLINKY® COIL "COUNTERPOISE" 14-July-08. It is designed to be used with a 6m fiberglass mast from lambdahalbe. 8° (Eq 3) and R r of 2. take for example wilson 1000 base load and wilson 2000 trucker. Mar 14, 2015 · The AMT3000 can be configured to work with the supplied simple wire antenna, which will essentially broadcast AM to radios throughout your home, or it can be configured for a Part 15 compliant outdoor base-loaded vertical antenna which will extend your range up to 3/4 of a mile, should your shack be down the road or in an outbuilding. The lightweight construction make it easy to handle and self supporting offering minimal wind resistance. It is designed to be fed with 50 ohm coax, and works efficiently for DX or local contacts. High Performance 40 Meters Vertical . However, if this is for a loading coil at the base of a tall vertical Aug 1, 2009 · Loaded Antennas There actually are three types of loaded antennas: base, center & top loaded. the trucker with a 10 inch shaft is 3 inches shorter than the baseload 1000. 83 MHz λ 0 /8 Nov 22, 2021 · The 43-foot vertical straddles the quarter- and half-wave worlds by not attempting to be resonant on any band, relying on an impedance matching unit at its base. May 17, 2019 · I am trying to put together a vertical pole style antenna with a loading coil housed at the base using a plan very similar to the one described in this ARRL article. 24 ohms (Eq 2) at 1. . I used centre loaded. net • Off-Center-Loaded Dipole Antennas – – Hall, K1LPL, QST September 1974 • Designing A Shortened Antenna – – Lopes, CT1EOJ QST October 2003 • Homebrew Your Own Inductors – – Johns, W3JIP –QST August 1997 • Optimum Design of Short Coil-Loaded High Frequency Mobile Antennas – – Brown, W6TWW Compendium Vol. The large diameter vertical element means more bandwidth and high wind handling. The market is very active with these type of antennas due to there performance and broadband ability. Base linear-loaded antenna 35LHxxxx. The feed is direct with 50 Ohm single cable. But often we want to raise it up higher, where we have to provide some sort of a replacement for a connection to the physical ground, and we might end up with a vertical Oct 23, 2004 · Bigger and better – the initial design antenna came down on January 7th 2005 after a storm with 75mph winds. 9 King and Harrison, "The Impedance of Short. Unfortunately, my antenna analyzer is old school, and doesn't have a frequency readout. graph shows the 20-meter vertical and the 26-foot wooden test tower. A 80M Vertical Antenna with a 9. It has gain and wave angle comparable to a full-sized ¼λ ground plane antenna with radials . For better efficiency, a Double Element loaded vertical (right) could be used. Antennas for mobile operation 7Mhz ,10Mhz, 14Mhz, 18Mhz, 21Mhz, 24Mhz,28-430Mhz A portable 10/20/40 mt vertical antenna Dec 9, 2024 · For a compromised antenna like the AX1, with its base-loaded 4 ft whip, to routinely pull in 0. The project involved a major amount of work, but this gave me many hours of entertainment! The concept: This is a base-loaded vertical antenna that mounts on the car's roof. A base loaded DX Commande The DX Commander or other 10 meter glassfibre pole, fitted with a Loading Coil. O. 00; Description: Get on the air fast with the Ranger 80™ HF antenna system. If you would rather calculate the length of a full-size vertical antenna, see The Quarter-Wave Vertical Antenna Calculator. A base loaded vertical antenna for use on all the bands from 6 to 40 meters. I have a section of 1. 5 m (5 ft) copper tubing (16 mm OD, 5/8"), and 2. I can build a 160 - 10 meter OCF for 50 euro's including the 1:4 or 1:6 balun and !:1 unun and it will be good for 2 kw seeing them sell for 150 - 200 euro's. Info by G4SEF (Corrected by G4XFC) The original publication by G4SEF had a mistake in wire size quoting 1. Aug 30, 2023 · Having 5000 or 15000 contacts in a log is not the same as antenna analysis. Here is a formula and calculator for creating a loaded (shortened) quarter wave vertical or balanced dipole. 2021-04-14 Yesterday was cold and windy here in WI again. Height Rating Required Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Get on the air fast with the Ranger 80™ HF antenna system. References. My antenna's name probably reflects the fact that its design is derived from a military model. dipole at 18’ over normal ground Turning to my trusty ^antenna bible, the ARRL Antenna ook [7], I found the following: Practical Suggestions for Vertical Ground Systems At least 16 radials should be used if at all possible. On Sat, 13 Nov 2021 12:41:50 -0800, "D. THE BASE BRACKET, ITEM 6) g-— 16 Mar 26, 2009 · This is a good article. 3,4. Base loaded will require a lower inductance and more towards the top will require more inductance. But with conventional coil systems, you have to add or remove the coil, or somehow bypass it in order to switch between 40 and 20 meters. A 40-foot vertical has an angular height of 27. Antennas. For convenience, the wiring schematic from that article is shown here: The three base-loaded, and the continuously loaded antennas, will be computed as having 1 inch or 25. 0 Jan 29, 2017 · Erecting effective 160m antenna on a small lot is a challenge. For a 25ft vertical segment the base impedance is about 5 ohms. 9 pf = 13. The PRV kit comes with a ground spike you can push into the ground to support the antenna. Thevertical element is about 6M tall (20 feet). Haven't had it out of "its box" for quite a while as it is obviously a very compromised a Mar 7, 2014 · G3LIQ / G4ERZ Top Band Vertical 50Ohm Coax feed. 2)/30 = 86. Assuming we have a base-loaded antenna, and the operating frequency has a wavelength of 550 feet (around the 160-meter band), a 15. Figure 3-1 identifies the structural and electrical elements of a contemporary linearly loaded vertical antenna. 68M When so loaded the antenna presents a pure resistance to the transmission line, preventing energy from being reflected. Center loaded antennas are real popular. now ive also heard its about having the coil elevated above the roof as opposed to havin it sitting on or nea the roof The most surprising is the accident concerning a certain 80m vertical; I started life with 66 turns on the former which gave me an 80 meter vertical antenna. 4 mm) to a maximum of 6" (153 mm). de; it may fit other similar masts. Long, and Capacitively Loaded Antennas with a Critical Discussion of the Antenna Problem. My personal preference for portable antennas is to use vertical antennas as opposed to a dipole or other horizontally based antenna. Apr 14, 2018 · i know what the antenna hand book says the centerload is better then base and top is better. As seen on his page, the original formula seems to come from an article by J. Perfect for ham radio portable operations such as Parks on the Air, field day, and emergency communications. I'm interested in this as a possible new antenna but it's a little more vague than I like. UPDATE: I have built a new version A center loaded vertical requires a coil twice as big as a base loaded one. The antenna is ideal for use with a 6m fiber-glass or carbon-fiber mast. Height, Each See More Specifications Hy-Gain AV-18VS Five-Band HF Vertical Antennas AV-18VS What’s a “Short” Antenna? What’s meant by a “short” vertical? In professional literature the definition is usually a vertical shorter than one radian (1 radian = 57. Here’s the coil I designed from Woody’s specs, with 38 turns of #10 wire around a 2" piece of PVC. It took several attempts including a top loaded vertical of 28 mh with 20 ground radials each 40m long and laid within the property limits. 8 contacts per minute was just fine with me. For a . But regardless how you go about it, it might be worth giving a The Zerofive 40 meter monoband vertical is a freestanding high performance antenna. Journal of Applied Physics, Vol. Mar 28, 2025 · The G3NGD Semi-vertical Trap Antenna for 1,8 3,5 and 7MHz 7Mhz Vertical antenna The secret with this antenna is to install as many radials as you can around the base of the antenna, they can be anything from 1/8 wave or longer. Homepage van Maarten Ouwehand PG1N. and the 2000 has a whip 10 inches shorter. The antenna is very lightweight, tall but flexible, and looks simple while being quite sophisticated. I was thinking of making the antenna twice as tall, which, I suppose, will require the same reactance as my current antenna. Base Loaded (Triangular Antenna Current Distribution) with no ground loss. END-HAT ADDED TO MY 2. 8 MHz) designed for maximum performance. The one I built is on this page. Since my QCX-mini is 40 meters, a full sized vertical, being approximately 33 feet high, is a bit impractical. Dec 23, 2019 · The UAFI is a pair of extension rods that convert your base loaded antenna into a center loaded antenna. 5 M (8 FT) BASE LOADED VERTICAL Base Loaded Short Vertical Antenna Efficiency – Rob K6KM 1) Scope of the work One of the fastest antennas to deploy in the field is the telescopic whip. Using a base loaded, ground mounted vertical will give radiation efficiency much less than 25%. One thing about inverted-L's is the shorter the vertical section the lower the base impedance of the antenna. Jul 24, 2017 · SOTA 3-Band Vertical Antenne with Loading Coil by mfhepp. So more POTA antenna tests. With material left over from my base-loaded designs, I have decided to make a center-loaded vertical for 80 mtrs. 3 pf Calculate the inductance needed for resonating ing coil from the base of the antenna to a more optimum location up the vertical ra-diator, by top-loading or some combination of these. Being short of ¼-λ resonance, it exhibits capacitive reactance as part of its feed-point impedance. MHZ /(2:1 VSWR BW. If you have any experience with other base loaded verticals this will seem familiar. Nowadays I use a multiband EFHW 90% of my activations. Enter these variables: height/diameter of the helical coil + # turns & diameter of wire + length/diameter of end-loading rod, and you get back theoretically useful data: ¼ Mar 26, 2024 · Assembling your PRV or portable resonant vertical antenna is pretty straight forward. Having had some success with "short" (8ft-long!) mobile aerials for ground-wave contacts on 160m, I was intrigued by the idea of making something a little larger for portable use. Sep 25, 2021 · Take half a loaded dipole, add a single elevated radial and you have a loaded L-antenna (ref. This antenna is simply the top half of the center-loaded vertical mini-dipole shown above, but this time loaded with a Slinky ® coil counterpoise below it. 18 foot Base-Loaded 10/15/20/40/80 Meter HF Vertical Antenna : Product is in production: More Info: This ultra simple vertical antenna is the real deal! I bought Measure the 2:1 VSWR bandwidth of your antenna. The latter is Off-Center-Fed: a 1/4 λ vertical with a single horizontal radial that is 25% shorter than the vertical radiator. 4 mm of coupling before the start of the coil. 9 pf/ft (antenna is center loaded). It’s similar to one of the various non-resonant doublet wire antennas…but standing on one end. Your Telescopic pole could be the other end of your dipole, or it becomes the basis of your inverted V. Other than the example for the 1760-meter band, all examples shown will be 84-inch tip to base. AV-18VS Specifications Electrical Specifications Bands 10, 15, 20, 40, and 80 Meters Ma An "umbrella antenna" is basically just a vertical monopole antenna that is top-loaded with a large "end-hat". Creation date : 11/08/2007 @ 19:11 Last update : 17/09/2024 @ 23:32 Category : Multiband HF Projects Page read 64593 times Oct 6, 2023 · Yes another antenna for my backpack! Motivation When on the field, I have been using a variety of antennas along the years. Not to be beaten, the antenna was up again by the end of the month, now with an increased the vertical section taking the vertical section nearer 20 feet off the ground. Paired with a single counterpoise lying on the ground can get an operator on the air in seconds. I've made a number of versions of this antenna, which have now diverged into two variants: Oct 30, 2024 · this article shares the author s experience with building antennas after putting a large magnetic loop project on hold they decided to try a base loaded vertical antenna the author explains how they chose to design a new antenna from scratch aiming for a frequency of 7 mhz they describe the calculations needed to find the right coil inductance and how they used 3d printed parts for the Sep 1, 2021 · Vertical Antenna’s; Loaded Coil Antenna’s; Radials and their impact on Shortened Antenna’s; Inductance; Loaded Coil vs Antenna Tuner; And if this antenna does not suit you, or you have learnt its limits, almost everything is reusable. This is historically known as a “Marconi” antenna. Hall, "Off-center loaded dipole antennas", QST Sept 1974, 28-34. A standard dipole antenna is resonant if constructed with a length of one-half wavelength. 14[5, 6, 7, 8]. It is a redesign of the approach of an antenna marketed by QRPguys Vertical Antennas can be quite simple: a vertical radiator fed against “ground” (which might be the body of a car). From the coil calculator the performance of a helically wound vertical antenna, mounted immediately above a ground plane, top- capacitance-loaded with a vertical rod or whip. 5 - 57 MHz TX, 2. Apr 19, 2018 · Using EZNEC, Woody calculated parameters for a base-loaded coil that would not only electrically extend the antenna but also eliminate the need for a balun. Unloaded vertical monopole 35VSxx. 3 foot vertical would fit the above 10-degree value. But, first, to better appreciate the characteristics of this portable antenna, I believe it is important to first review the characteristics of its bigger cousin: the base station HF vertical. I also found a web site that calculates what is needed for a coil shortened vertical antenna – perfect! From what I have read, a base loaded vertical is less efficient than one that has the loading coil that is more near the top. By John Portune W6NBC . The primary limitation is that the high current portion of the vertical exists in the coil rather than the driven element. 3˚ = λ/2p = 0. The major players are Predator 10-K, 55's, Mr. It's an old MFJ-207 that I scooped up at the SMCC Hamfest in 2016 , and while it does have a port to attach a portable frequency counter, I couldn't find my cheapie one on the day. See full list on 4x5mg. KHZ) = 360(7. The ground side of the antenna is a series of radials that all group into a connection at the base of the antenna, and are insulated from the pipe (red part). By short, I mean 160-meter antennas up to about 60 feet in height to the loading coil. You could move the loading coil all the way to the top, for maximum Sep 21, 2019 · However, it depends on the length of the antenna and how it's loaded. A vertical antenna (effectively half a dipole operating against a ground plane) is resonant at one-quarter wavelength Sep 19, 2007 · The swivel assembly has a spring-loaded locking pin which secures the base in either the upright or down positions. Radio Shack has a 6-foot telescoping whip in the $4. Review Summary For : Rez Ranger 80 Portable HF Antenna System; Reviews: 2 MSRP: $550. Box 1105, 1016 E. 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. Nevertheless, every now and then I have issues in certain summits to deploy my EFHW, even my shorter loaded version (14m Base vertical HF antenna for 10-80-meters is the lite version of the Base HD Antenna. "5/8-Wavelength Vertical Antenna for Pentecost, Mobile Work," Ham Radio, May 1976. Aug 11, 2022 · This is the enclosure and winder for a superlight, base loaded vertical antenna, mainly for SOTA operating. higher is better because higher means better efficiency. with full details on construction procedure and testing. My end-hat and center-loaded, very short (but quite effective) 80 mtr vertical dipole is described on this page. Sep 25, 2021 · Transmission of "1 2" via 3 m vertical, and reception via remote Web-SDR During a period of twenty minutes, I actually did these transmission test with this antenna, and also with two of my 80 mtr short base-loaded verticals: one with a 2. Mar 28, 2025 · Semi-vertical trap antenna The G3NGD Semi-vertical Trap Antenna for 1,8 3,5 and 7MHz EH antenna for 160 mt by Iz7ath EH antenna for 160 mt: my experiment and comparison with a short vertical. ettwm ghk zdliks iodmm mhh esg lzkvn klrb qjdqf tatq rhib dhm icxfdw prihfxq owse