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IK4DCS experience on maintaining a multiband delta loop antenna for 10/12/20 meters.

The basic antenna is a vertical monopole, using elevated radials to complete the ground plane by k5oe

Autotena, a Taiwanese manufacturer, offers a diverse product line focused on RF communication antennas and related accessories. The resource details various antenna types, including **4G/3G LTE wideband high-gain low-profile antennas**, land mobile wideband antennas, fiberglass omnidirectional designs, and GPS mobile and marine antennas. Specific amateur radio offerings include NMO VHF load coil gain antennas, VHF whip gain antennas with PL-259 connectors, and UHF NMO mount antennas with 3dB/5dB gain. The company also produces antennas for CB and 10-meter amateur bands, such as aluminum broadband 26-30MHz antennas and big copper coil broadband 26-30MHz antennas. Additionally, the site showcases **RF amplifiers** for CB, HF, VHF, and UHF bands, including professional-grade base station amplifiers with 100% EIA duty cycle. Handheld antennas, PL-259 type mobile antennas, magnet mount antennas, and external CB speakers are also presented, alongside various mounting kits and cable assemblies.

Mobile antennas, loading coil current, and loaded antennas. efficiency and electrical rules. Loading inductors used in mobile HF antennas.

Here are construction plans of a Turnstile antenna that can be used for space communication on the 2 meter amateur radio band. Specifically for 145.80 mHz

manufacturer of VHF and microwave antennas and related products, from 50 MHz through 10 GHz

Also known as W0MHS Loop Skywire or Full Wave Loop Antenna, here you can find N1SU interesting observations on this antennas.

46ft multi-band antenna for small gardens. Works well on 80m. An excellent DX performer and is an ideal replacement for your half size G5RV

This article describes how to make a quadrifilar helix (QFH) antenna easily, from inexpensive materials: uPVC plumbing pipe and RG-58U co-axial cable

The total length of the inverted L is 240 feet, which is 7/16th of a wave length long. It has a 92 foot horizontal linear load section 1 foot above ground that terminates into a home-brewed parallel network tuner by KN4LF

A delta loop antenna project for the 40 meters band, include dimensions 80 meters band, with construction details, schematic and tuning instructions

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

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

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

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

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

Home made bazooka antenna for 2 meters band

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

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.

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.

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.

Project by VE7GC

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.

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

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

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

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

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.

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

Dual band rectangular loop antenna for 15m and 10m

Calculate dimension for discone antennas online

VK2ZAY end-fed antenna for 40 and 80 meter band

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

A 3 element yagi antenna for 17 meters

Schematic for a DIY 70 cm vertical antenna

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

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.

The slim-jim antenna for 144 MHz

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.

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

A VHF Quad antenna for teh two meters band in italian

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.

2 meter or Dual Band J-pole bicycle antenna

Makers of motorized antennas covering 6 to 160 meters