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A homemade Magnetic Loop antenna from a spare 3m length of RG213 working from 30m to 15m with a 130pF tuning capacitor

This is a collection of articles, generally from QRP-L, about QRP operations and portable antennas. However, anything that looks interesting to me might end up here. These articles are posted here primarily for my own use; however, all are free to browse.

Buildin a VHF Jpole antenna with detailed pictures

A simple and low cost multiband vertical hf antenna covering 5 bands (20m-10m) from an old CB antenna

A small antenna for all amateur bands, including 80 meters, and in a small garden without the compromise. An ideal replacement for those half size antennas such as the 1/2 size G5RV and Windom 40

Easy for calculate formula which could be a wake-up call for you. The SWR value at the input of antenna cable is not a actual SWR of your favorite antenna.

A vertical monoband that's small, light and portable, needs no counterpoise and performs as well as a home antenna

A Moxon rectangle antenna projects for the 6 10 15 17 and 20 meter band but include drawings, plans, statistics and homebrewing statistics.

Includes EH antennas, 7Mhz vertical monopoles, 5 elements vee log-yagi for 10m and more

This high antenna require a large ground composed by 40 radials. It's not very handy expecially in windy situations but is very powerfull in pile-ups. In italian

Home made bazooka antenna for 2 meters band

A High Efficiency Extended Length Mobile Antenna The antenna itself is 3.42 meters or 11 feet 2 inches long from the top of the mounting spring to the tip.

Project by VE7GC

End-Fed Half-Wave Antennas (EFHWAs) are analyzed for their utility in portable QRP operations, emphasizing their simplicity, efficiency, and predictable radiation patterns compared to other portable antenna types. The discussion contrasts EFHWAs with vertical antennas, random length wires, and center-fed dipoles, highlighting the common pitfalls of each, such as ground system dependency for verticals and feedline issues for dipoles. The article details the electrical half-wavelength calculation using the formula L (Ft) = 468/F(MHz) and explains how EFHWAs can be resonant on harmonic frequencies, enabling multiband operation. Various deployment configurations are presented, including the inverted L, inverted Vee, sloping wire, and vertical setups, each with specific advantages for radiation angle and polarization. For instance, a vertical EFHWA offers a low angle of radiation suitable for DX contacts without requiring an extensive ground system. The resource also addresses the counterpoise requirements, suggesting a quarter-wavelength wire or connection to a metallic structure for decoupling. A schematic diagram for a simple parallel-tuned circuit tuner, based on the _Rainbow Bridge/Tuner_ design, is provided, detailing component values for 30 and 40 meters, including a 6 microhenry toroidal inductor and a 20-100 picofarad mica compression capacitor. The tuner's adjustment process for SWR matching is also outlined.

Over 75 years of engineering expertise underpins Bird Electronic's offerings in RF power measurement, critical for maintaining peak performance in amateur radio stations and professional communication systems. The company specializes in a range of test equipment, including wattmeters, SWR meters, and antenna analyzers, essential for optimizing antenna systems and ensuring efficient power transfer. Their product line extends to various RF components such as filters, cables, and connectors, all designed to meet stringent technical specifications for reliability and accuracy across diverse frequency bands. Bird Electronic's instruments, like the _Bird 43_ Thruline Wattmeter, are widely recognized for their robust construction and precise measurement capabilities, providing hams with confidence in their station's operational parameters. These tools enable accurate assessment of forward and reflected power, SWR, and modulation characteristics, which are vital for troubleshooting and maximizing radiated power. The company's commitment to innovation ensures that its products remain relevant for modern RF challenges, from HF through microwave applications, supporting both traditional analog and advanced digital modes.

An interesting rotator interface that interfaces a pc to a rotor or rotator controller, emulating a Yaesu GS-232A/B and Easycom protocols, made with Arduino

The function of the calculator is to give all of the needed sizing to construct a good 5 element quad antenna for amateur radio use.

Calculate dimension for discone antennas online

Homebrew Sector Antenna for Wifi ISM band (2,4GHz)

Portable Vertical Antenna for 75m and 40m featuring Low radiation angle for DX, easy to install and to match 50 ohms

Schematic for a DIY 70 cm vertical antenna

Two element X-Beam is a high-performance broad-band antenna that is ideal for Ham radio operators with limited space. X-Beams are inexpensive and easy to build. The performance of the simple X-beam is amazingly similar to larger, more conventional antennas by 4S7NR

This is a base-loaded vertical antenna that mounts on the car's roof. The loading coil is designed as a variable inductor, with a three-legged chariot that travels up and down inside the coil, with grooved brass wheels running on the coil turns, and driven by a slotted rotor tube.

Dual band rectangular loop antenna for 15m and 10m

VK2ZAY end-fed antenna for 40 and 80 meter band

A VHF / UHF J-pole vertical antenna de ON6MU

It is very easy to create a simple 1/2 wave dipole, all you need is some lengths of wire such as the core of some mains flex or even a straightened out metal coat hanger, some co-ax cable and a connector for your scanners antenna input

N6RK receive only loop antenna

G3YCC article pn the W3EDP end-fed antenna for 80 to 20 meters bands

Wikipedia page about collinear antenna arrays

This is an antenna that author just built. Was intend for receiving the AO-27 downlink (at 436.800 +/- doppler). It is built with right hand circular polarization, and the gain is supposed to be in the neighborhood of 3 DB.

This PDF document, authored by KT4QW in October 2004, details the construction and modeling of a dual-band, horizontally polarized hanging rectangular loop antenna for **10 and 17 meters**. The design, adapted from *The ARRL Handbook*, utilizes _NEC4WIN95_ software for scaling and optimization, targeting a 50 ohm feedpoint impedance. The resource includes a bill of materials, step-by-step construction instructions, and a discussion of the antenna's radiation characteristics. It presents NEC-generated elevation and azimuth patterns, comparing the loop's performance to a half-wave horizontal dipole at the same height and frequency. The 17-meter element is centered at 18.140 MHz for low SWR across the phone band, while the 10-meter element is centered at 28.500 MHz. Construction involves 14-gauge stranded copper wire and Schedule 40 PVC spreaders, with the total wire length calculated by the formula: Length in feet = 1005/MHz. The feedpoint impedance can be adjusted by modifying the rectangular aspect ratio. The document specifies hoisting the antenna to at least a half-wave above ground for testing. It notes that a balun was tested and found to have no measurable effect on SWR or radiation characteristics. A 2-meter scale model is presented to illustrate the physical design, and a "rotator" string is incorporated for directional adjustment up to 90 degrees.

Yagis for 20 15 10 meters band by Nathan A. Miller

G8OFZ multi-band antenna for 80-10m, this antenna appears to be a derivative of the Doublet and the Classic G5RV

The slim-jim antenna for 144 MHz

A standard 6 elements design scaled for UHF application. All material used in this project are easily obtainable tubes and rods which is limited within a total budget of $18.

Makers of motorized antennas covering 6 to 160 meters

70cms Simple Moxon 2 elements antenna

2 meter or Dual Band J-pole bicycle antenna

The Buddipole website showcases a range of portable amateur radio antenna systems, including the **Buddipole**, Mini-Buddipole, Buddistick PRO, and BuddiHEX, designed for rapid deployment and multi-band operation from 40 meters to 2 meters. Each product page details specifications, operational modes (dipole or vertical), and compatible accessories like tripods, masts, and baluns. The site also features portable DC power management systems such as the PowerMini 2 and PowerPlus, which include integrated battery chargers and solar controllers, catering to off-grid or field day setups. Instructional videos demonstrate antenna assembly, tuning, and deployment techniques for various configurations, including the VersaTee vertical and Mini-Buddipole. Customer testimonials and DXpedition highlights, such as operations from Montserrat (VP2M) and Dominica (J38), provide real-world examples of the equipment's performance in challenging environments. The company, established in 2001, emphasizes modularity, versatility, and efficiency in its product line, all manufactured in the USA. Shipping information, a 30-day return policy with no restocking fee, and contact details for their Heber City, Utah facility are clearly presented. The site serves as a direct sales portal, offering a comprehensive catalog of antennas, power solutions, and components for portable amateur radio enthusiasts.

If you find external wire antennas obtrusive for amateur radio or short wave listening, then this is the antenna for you, is just 1 meter diameter

Remotely tuned 1m diameter HF loop antenna for 7 to 29MHz by G8JNJ

How to build a high gain vertical antenna for the UHF amateur or CB Bands, by radio experimenters handbook

homebrew an helix antenna for 435 MHz by VE2ZAZ

A multiband end-fed antenna that cover 3.5 to 30 Mhz using a 1:64 Balun based on a FT240-43 core

WorldRadio Article on Petlowany antennas base on this principle: 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

Amateur radio towers by Wade Antenna ltd. Wallmounts,masts and accessories, tripods, dmx self spporting towers, telescoping masts

A coaxial cable tuneable magnetic loop antenna for 7MHz. This experimental antenna does not require a tuning capacitor

The ultimate satellite Omni Antenna by Howard Sodja, W6SHP. The Lindenblad antenna consists of four half wave folded dipoles slanted 30 degrees to the horizon, oriented 90 degrees to each other in azimuth, spaced 0.3 wavelength apart

About Stacking yagi antennas by OH1ZAA