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Land communications and marine antennas

J-pole antenna made easy using a twinlead by W4ZT

An homebrew crossed Yagi antenna for two meters band based on DK72B design with pictures, detailed description and tricks by Barry Zarucki M0DGQ

Different band dipoles can be put together with a single feed, learn how by W8HDU

The Classic Multiband Dipole Antenna QST article. The open-wire feed line dipole antenna is easy to install and offers surprising performance on several bands. You can install it in almost any configuration; it does not have to be strung in the traditional horizontal flat top

Radial systems for elevated and ground mounted vertical antennas by SteppIR

This transceiver was conceived as a power-efficient, small, lighweight unit to be carried in the backpack, along with antenna and battery.

This is a 200 Watt PEP step up transformer for end fed full and half wave antennas without radials, designed as a 200 Watt PEP

Ham Radio On line shop, kenwood yaesu icom alincon ten tec dealer, antenna rotors, antennas, antenna mounts, microphones, antenna mas, receivers and scanners based in Essex England Uk

Helical antennas invented by John Kraus give a circular polarized wave. They are one of the easiest to design. Find a tube with a circumference equal to one wavelength, and wrap wire in a helix spaced a quarter wavelengt

Definition of antenna gain at wikipedia

The Crossed Field Antenna (CFA) is one of the applications of Correction of Maxwell's Equations which was used over 150 years ago which was proved these days that the Magnetic Field Source is only the Displacement Current not the Conduction Current . These Corrections was made by an Egyptian Doctor Engineer Fathi Kabbary , who reached the New Correct Theory which shows that the height and efficiency of the antenna doesn't depend on the wavelength

The antenna is an inexpensive, multiband, end fed HF antenna. It has a matching network consisting of a toroid core and an antenna lead of 30

Pickup truck stake pocket antenna mount by geotool

Build an HF antenna tuner by VK5AJL

Operating a ZS6BKW antenna often involves understanding its lineage from the _G5RV_ design, with specific modifications by ZS6BKW to optimize performance on several bands. Through computational analysis and field measurements, the antenna's dimensions were refined to allow operation on 10, 12, 17, 20, and 40 meters without an antenna tuner. For 80, 30, and 15 meters, a tuner is necessary, though efficiency on 30 and 15 meters is noted as not particularly high. The physical configuration consists of two 13.755-meter radiating elements fed by a 12.20-meter section of 450-ohm ladder line. Tuning the antenna on the 20-meter band is critical, and any deviation in the ladder line's characteristic impedance necessitates recalculating the element lengths. The design is also referenced in the 12th edition of _Rothammel's Antennenbuch_, page 219. Proper common mode current suppression is crucial at the transition from ladder line to coaxial cable. This can be achieved with a common mode choke, such as several turns of coax wound into a coil or over a ferrite toroid like an Amidon T130. While a 1:1 balun is an option, it may introduce issues.

Loop antennae have been used from ELF to UHF since the beginning of radiocommunications. At low frequencies, the main problem for loop antennae is to have enough sensitivity; the antenna being very small respect to the wavelength the collected energy is also small. To increase the output level the loop may be made resonant, so loosing it%u2019s intrinsic aperiodic characteristics.

40 meter vertical antenna construction, a shortened easy-to-build vertical, with no-radials, made from surplus military camouflage poles

A vertical antenna specifically designed to work with the 80 meter CW beacon keyer

Sharing information on Topband Homebrew Antennas, Base & Mobile

A vertical dipole for 10, 15, 20 and 40 meters made adapting two Hustler Model 6-BTV antennas by w6sdo

A home made vertical polarized moxon antenna for 144 MHz, includes dimensions, antenna pattern, SWR and antenna gain plots by WB5CXC

A six meter Moxon rectangle antenna. Includes high definition pictures and a detailed drawing by KG4JJH

Yet another G5RV antenna plan to build a G5RV Antenna for 80 to 10 meters usage

This project will enable you to build a monoband long wire inverted vee with 3/4 wave length sides that will have a bit of gain

HD Communications Corp specializes in **RF and microwave amplifiers** engineered for demanding communication, defense, and industrial applications. Their product line includes precision-built, high-power solutions, along with RF connectors, filters, HF cables, and various accessories. The company also supplies tower hardware, valves, and tubes, catering to a broad spectrum of radio frequency infrastructure needs. Beyond amplifiers, HD Communications offers a range of **RF filters**, including low-pass filters, antenna filters, and solutions for RFI/TVI mitigation. Their inventory encompasses essential components like coaxial cable and various connector types, supporting both amateur radio and professional installations. The company operates as a manufacturer and vendor, providing direct sales of its specialized RF products.

318 and 200 ft insulated towers

A portable 4 elements quad antenna for 144 MHz, 9 to 10 DBd forward gain, 30 DB front-to-back ratio, and 33 DB front-to-side ratio

A three element wire yagi antenna for 7 MHz project plan with drawings and EZNEC model

A compact Quad Antenna for the HF Bands by GM0ONX

A 90-foot vertical antenna constructed from **aluminum irrigation tubing** is detailed, focusing on its innovative raising and lowering mechanism. The resource describes a **45-foot ginpole** system, allowing a single operator to erect or lower the antenna in minutes. It covers the mechanical design, including the pivot base, insulated joints for the tubing sections, and guy wire attachment points. The antenna consists of two 30-foot sections of 4-inch tubing and one 30-foot section of 2-inch tubing, stacked with the smaller diameter at the top. The electrical design incorporates PVC "condulet" boxes at the 30-foot and 60-foot points, housing relays to change the effective height for multi-band operation on 160, 80, 40, and 30 meters. Ferrite rod inductive chokes are used for DC control and to tune out gap capacitance. The antenna is fed with 1000 feet of open wire line, connected to a matching transformer comprising stacked toroids and a coaxial/toroidal balun. Grounding is achieved with a 3x3 foot grid of 16-gauge tinned copper wires with soldered crossovers.

A simple vertical antenna for 70 cm band

PA5DD version of the dual band yagi antenna for 50 and 70 Mhz

TRasceivers HF-VHF-UHF, repeaters, GPS, antennas, based in italy

Outbacker mobile and portable antenna systems are slim line, highly efficient, single whip multi bond antennas for vehicular and limited space portable applications.

A full size delta loop antenna for top band by PA3FUN

Dutch Antenna and Tower Manufacturers from Slimline Square Triangular Round Towers. Antennas production include Yagi Monoband/Dipole/HF Quad /50MHz and 70MHz Yagi-Quad, VHF-UHF yagi-Quad and Comby antennas VHF/UHF/SHF

It consists of a radiating wire with a length equal to the half-wave of the fundamental frequency for which the antenna is cut.

Cheap and EZ to build Bi-Directional VHF & HF antennas with gain

This design was adapted from an article in the ARRL Handbook and built with simplicity and duplicity in mind. This antenna is a vast improvement over a standard dipole with a forward gain of around 8db with a front to back ratio of 10db.

A marriage of the windom and slinky antennasm, article by NC4TC

A folded wire antenna for 160 meters as appeared on 73 amateur radio magazine june 1997

An cheap, easy to construct and not too visible antenna for the low bands

A simple online folded dipole antenna calculator

A compact multiband wire antenna suitable for portable operations.

An interesting arduino project to work as an antenna tuner

A copper pipe Hentenna for 144 MHz. The Hentenna, a compact, high-gain loop antenna developed in Japan in the 1970s, offers approximately 5.1 dBd gain, comparable to a three-element Yagi. Adapted for 2 meters, it is crafted from copper pipe for simplicity, affordability, and broadband performance. Requiring no feed-point tuning, its construction involves soldering standard copper fittings. Installation demands non-conductive materials to minimize signal disruption. Versatile for vertical or horizontal polarization, it is ideal for FM, repeater, SSB, or CW applications. This design emphasizes practicality and performance for amateur radio enthusiasts

A vertical antenna project than can present low swr from 40 to 10 meters by using a balun in french

DK7ZB 9 element antenna

This antenna consists of 4 resonate dipoles made from 12 insulated copper electrical wire. The dipoles are resonate on the following bands: 6 meters, 10 meters, 12 meters and 17 meters.