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Build the PAC-12 Antenna a multi-band portable vertical designed by KA5DVS, here's an award-winning, easy-to-homebrew, multi-band portable vertical antenna designed by long-time antenna aficionado James Bennett, KA5DVS. He's documented the design and construction plans for a portable antenna

A **mobile HF multiband antenna** project details the construction of a center and top-loaded design, optimized for 10 through 80 meters. This antenna incorporates a capacity hat positioned high on the whip for enhanced efficiency, differing from commercial bugcatcher designs. The coil construction prioritizes high Q and minimal loss through an air core, open spacing, and heavy gauge wire, contributing to its lightweight nature and suitability for portable operation with a proper counterpoise. Band switching is achieved by manually moving a jumper plug to various tap points on the coil, allowing for operation across multiple bands, with 17m being resonant when the coil is bypassed. The design, a result of nine months of experimentation by N1LO, includes detailed instructions for modifying a Hamstick antenna base, creating a jumper wire, and assembling the capacity hat using stainless steel wire and silver-bearing solder for robust connections. The loading coil utilizes nylon grommet strips around a PVC pipe for an air-core winding, ensuring high efficiency. Tap sockets are fashioned from silver-plated 5-way binding posts, providing low-resistance RF joints for band selection. Guidance on tap point determination emphasizes using an antenna analyzer like the MFJ 259B or 269 to achieve resonance, especially on 40m and 80m where feedpoint resistance can be low. The document also covers the installation of monofilament stays to maintain antenna uprightness at highway speeds, with specific attachment points for stability.

Pictures of 2.4 Ghz antennas, JN1GKZ S-band homemade antennas

This homebrew legal-limit antenna tuner is based on the famous "Ultimate Transmatch" introduced by the late Lew McCoy, W1ICP. The Ultimate Transmatch was described in the "Beginner and Novice" section of the July 1970 QST (Page 24).

Calculates resonant frequency of a loop antenna, correcting for distributed capacitance.

A dual-bander for 80M and 40m. An Extended Double Zepp (EDZ) is a 5/4 wavelength center-fed dipole. This article will introduce the Half-Extended Double Zepp (HEDZ) which has characteristics that a lot of amateur radio operators should find quite interesting

Article with detailed pictures of an endfeed antennna for 20 and 30 meter band

A portable antenna for mode B and J satellites

DIY Basic Electronic Theory, Basic Antenna Theory with Antennas built from common materials. What does SWR really mean. Baluns from transmission line.

The _Morgain_ antenna for 40/80 meters is a straightforward and cost-effective wire antenna design, requiring careful tuning for optimal performance across two bands with low SWR. Construction involves creating 12 cm PVC spacers with three holes for wire insertion, along with larger terminals for anchoring and connector housing, which should be sealed with silicone. The provided measurements detail the specific lengths for the antenna elements, crucial for achieving resonance on both 40m and 80m bands. Tuning the Morgain antenna necessitates fabricating four wire segments with pins to temporarily connect and adjust the bridging points symmetrically for both 40m and 80m. This iterative process, though time-consuming, ensures the antenna functions effectively for decades once the precise connection points are soldered and protected. The design emphasizes ease of construction and long-term stability, making it a practical solution for hams seeking a dual-band wire antenna.

This drawing shows a simple 10 meter wire J-pole antenna designed for 28.4 MHz. It is a vertical, end-fed Zepp-style antenna made from common materials and intended for easy home construction. The main radiating element is a straight length of stranded copper wire, either 14 or 18 gauge, cut to about 16.5 feet. At the top, the wire is supported by an insulator, allowing the antenna to be hoisted vertically. The matching section is made from 450-ohm ladder line, approximately 7 feet 9.5 inches long, and shorted at the bottom. This matching stub transforms the impedance so the antenna can be fed with coaxial cable. The feed point is tapped about 6 inches above the bottom of the stub, with the shield and center conductor connected at the proper points. A choke balun is formed with five turns of RG-58 coax in a 4-inch diameter loop to help reduce unwanted RF on the feed line. The drawing notes that this antenna has about 0 dBd gain, similar to a dipole, but offers an omnidirectional pattern and low-angle radiation when installed high. Its main advantage is practical performance, simple construction, and effective coverage for 10 meter operation.

The 20-meter homebrew **Moxon antenna** project by 9Y4DD, Dave, details the construction of a 14 MHz directional antenna using readily available and repurposed materials. Initial SWR readings at 6 feet were 1.2 at 14.000 MHz, 1.4 at 14.350 MHz, and 1.1 at 14.175 MHz, with a subsequent increase of 0.1 on all frequencies when raised to 15 feet. The design adheres to specifications provided by L.B. Cebik (W4RNL). Key components include a discarded domestic water pump pressure tank as the center mounting bracket, 1/2-inch PVC conduit for spreaders, and 1/2-inch CPVC hot water pipe inserts to enhance rigidity. The total weight of the antenna is 12.625 pounds, with a material cost of U.S.$36.63. The spreaders are 165 inches from the center, utilizing 2.5mm sq. stranded copper wire for the elements. Dave's design incorporates hexagonal 'spider webs' of waxed twine to stabilize the flexible PVC spreaders, addressing initial issues with wind-induced movement. Separators cut from 3/16-inch Plexiglas maintain an 8.6-inch element spacing. The antenna demonstrated effective DX contacts with Europe from Trinidad, showing improved noise reduction compared to an inverted V.

This Antenna is not really practical for AO-40 reception, but horn antennas have a number of qualities useful in microwave antenna testing and noise figure measurements.

Constructing and designing full size, single band stacked yagi antenna arrays

A QRP antenna tuner for 20 meters band

This rugged antenna, an omnidirectional collinear, is capable of surviving harsh environments. It's a good choice for repeater installations and can be top, or side mounted to the tower by WA6SVT

An interesting article about homebrewing antenna traps for multiband antennas by VE3GK

A detailed drawing of a VHF UHF Log periodic antenna by VA2PHI

Plans, photos, electrical and mechanical design for this HF Log periodic antenna.

The multi-band trapped dipole is resonant on approx 3.7, 7, 14, 24 7 28.5 Mhz. The overall top length needs to be approximately 32.9 Meters

The article details the construction of a "bug-catcher" style HF mobile antenna, emphasizing its low cost and ease of tuning. It outlines the use of readily available materials such as PVC pipe, #14 house wire for loading and matching coils, and a _RadioShack_ replacement whip antenna. The design allows for operation across 20 through 6 meters, achieving an SWR of **1.5:1** or less on each band segment. The resource provides a comprehensive materials list, step-by-step assembly instructions, and photographs illustrating key construction phases. It explains how to create the coil forms, wind the coils, and secure them with epoxy putty. Crucially, the guide includes a table of suggested coil-tap positions and whip extensions for specific bands, such as 6 turns on the matching coil and 8 turns on the loading coil for 20 meters, facilitating initial tuning. Furthermore, the document discusses installation considerations, including grounding, and offers practical advice for tuning the antenna using an SWR meter. It highlights the antenna's broadband characteristics and its ability to collapse the whip for garage storage, making it a practical solution for mobile HF operation. The author, KM4IE, shares personal experiences with worldwide CW and phone contacts using this antenna.

Even if using a tuner this multiband antenna will let you operate from 160 to 10 meters. If you could only put up one antenna, this would be it. Project by N0KHQ.

One is an EFHWA for 20-40 meters, and the other is a matching unit for the antenna by n0lx

How to select an antenna for scanning. This is a Readers Digest version of antennas, meant to give new users some idea of the different antennas and their good and bad points.

M1PAF's 20 Meter Vertical Moxon antenna design, based on Pete Mills' EZNEC model, utilizes a push-up GRP mast and Tufnol plate for mounting cross arms, minimizing metallic elements within the beam. Hydraulic pipe clamps, also plastic, secure the tube clamps, with only two bolts and a plate being metallic. Dog bone insulators with Kevlar line and snap links facilitate quick wire element attachment, ensuring tension in all dimensions. The antenna's support structure includes Tufnol guying rings for Kevlar guys, providing stability against high winds. The cross arms are constructed from three 1-meter sections, allowing for convenient packing. This portable setup was successfully deployed adjacent to the ocean, enabling over 4500 QSOs in six days with 100W, achieving easy contacts into Japan and Asia. The design emphasizes ease of erection by a single operator and robust performance in challenging environments. Components for the cross arms were sourced from Spiderbeam. Further information is available via M1PAF's QRZ.com details.

This antenna is intended as a simple, inexpensive solution for the newcomer to experiment across the 40m band (7.0-7.2MHz) when only restricted space is available

Article designed to answer basic questions about antennas

Concentric Open Loop Antenna Fed Off-Centre similar to the cobwebb antenna but resonating on 20-17-15-10 meters band

Guide to calculate effective gain of antennas

80m to 23cm beam antennas, oscar antennas, and antenna rotors

Sardine Can Antenna. is a BiQuad or Bi circle - wire length each side (8 x 1/4 waves ) 31 mm

The finest in VHF/UHF antennas for Amateur and Commercial Applications. Antennas and Repeater Controller Accessories includes Rutland Arrays.

Article by Ed WE6W on a double bazooka antenna

Moxon antenna for 50 MHz, The Moxon rectangle is a quite broad-band antenna, but it is not quite broad enough to cover the entire band.

40 meters band Delta loop antenna plan that is vertically polarised

2el 40Ft front to back spacing 80 meters Quad antenna

What is the best balcony antenna? what antenna would you recommend for use on typical hotel balcony? Read some answers here

The resource provides detailed information about a five-band indoor magnetic loop antenna designed for amateur radio operators. This antenna is capable of operating on the 20, 17, 15, 12, and 10 meter bands, making it a versatile choice for various HF communications. Constructed from a single 3-meter length of 22 mm copper tube, the design emphasizes compactness and efficiency, which is particularly beneficial for operators with limited space. The page includes insights into the construction process, tuning, and operational tips, catering to both novice and experienced users. In addition to the technical specifications, the resource also discusses the advantages of using a magnetic loop antenna indoors, such as reduced interference and improved performance in urban environments. It serves as a practical guide for those interested in building their own antenna, offering a straightforward approach to antenna design and construction. Overall, this resource is a valuable addition to the toolkit of amateur radio enthusiasts looking to enhance their station with an effective indoor antenna solution.

Antenna Tuner operation, correct way to tune an antenna.

HF VHF/UHF yagi and quad antennas, towers and headphones manufactured in holland

The PringlesCantenna is an ultracheap Yagi-type directional antenna that can be built for under $10. The original Pringles Yagi was designed by Andrew Clap.

Arrl document about invisible antennas and indoor systems. It is important to consider that few compromise antennas are capable of delivering the performance one can expect from the full-size variety. But the patient and skillful operator can often do as well as some fellows who are equipped with high power and full-size antennas. The "cliff-dweller" may not be able to "bore a hole" in the band as often, and as easily, but DX can be worked successfully when band conditions are suitable.

How to make a simple but effective Slim Jim antenna. It includes a calculator to work out all the mesurements for the frequency you require.

A double bazooka antenna plan for the cw portion of the 40 meter band

An easy to build Hexbeam antenna built with bamboo sticks for the six meters band

Demonstrates the construction and on-air performance of the _NB6Zep_ antenna, a modified 20-meter Extended Double Zepp design optimized for multi-band operation from 40 through 10 meters. The resource covers basic design principles, including dimensions of 66 feet horizontal and 5 feet vertical elements, and specifies open ladder line or TV twin lead for the transmission line. It details material selection for low-cost wire antenna construction, such as 18 AWG wire for the legs and ceramic or plastic insulators, along with practical tips for soldering connections and insulating against moisture. The author, NB6Z, shares insights from extensive _EZNEC_ modeling to optimize the antenna's total length for a 40-meter half-wave dipole footprint and feed line length for direct tuner connection. The article presents field results, including successful _PSK31_ contacts from Oregon to the East Coast on 40 and 30 meters with 50 watts, even at a low height of 6 feet. It provides detailed performance characteristics for each band, noting the _NB6Zep_'s highest gain (over 3 dB) and sharp, medium-angle lobes on 20 meters, which yielded strong DX reports to locations like Korea, Japan, and Argentina. For 17 and 15 meters, it describes a butterfly-like pattern with broad lobes, while 12 and 10 meters exhibit narrow, directional lobes in an "X" configuration. The author also shares personal experiences operating successfully for over a decade in an antenna-restricted environment using the NB6Zep and other stealth wire antennas.

Constructing a compact, directional antenna for the 6-meter band presents unique challenges, especially for operators with limited space or those seeking portable solutions. This project details the build of a 50 MHz Moxon rectangle, specifically engineered for balcony or temporary mast deployment, using readily available materials from a typical hardware store. The design emphasizes ease of construction and portability, allowing for quick setup and breakdown. The antenna's dimensions are precisely calculated using _Moxgen_ software for 50.200 MHz, ensuring optimal performance. Key construction techniques include using aluminum U-channel for elements, fiberglass driveway markers for insulation, and cable ties for secure assembly. The guide provides detailed instructions for fabricating the driven element, reflector, and boom, including a clever method for creating foldable element tips for transport. Performance observations indicate a respectable front-to-back ratio, capable of reducing an S7 signal to S0 when pointed away, and a modest gain over a simple wire antenna. The design incorporates a ferrite bead choke balun at the feedpoint to mitigate common-mode current and reduce shack noise, a critical consideration for urban or apartment-based operations.

This page details the construction of a biquad antenna. The biquad antenna is easy to build, and provides a reliable 11dBi gain, with a fairly wide beamwidth.

Here you will find information about wire antennas as well as directional beams.

The W1GHZ Online Microwave Antenna Book online