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Portable, and shortened with loading coils rotatable dipoles for 6 meters, 20 meters and multibands.

Dipole antennas, unique broadband antennas, trap dipole antennas, coils, accessories for HF radio

A few hours of fun with PVC and wire and you have got yourself a respectable road radiator. The antenna consists of little more than some PVC pipe topped by a RadioShack replacement whip antenna and a couple of coils made from a small roll of #14 house wire.

This page describes the loading coil (inductor) that W8WWV built for my center-loaded 160 meter band (1.83 MHz) vertical antenna.

A new and simple method for tuning traps. You need 2-3Watt of your TRX and two homemade coupling coils by DK7ZB

This page explains how to construct high-Q inductor coils.

Basics for a good Antenna:``Only if you can hear it, you can work it!``Symmetric antennas save a lot of trouble.``No traps - no radials - no loading coils.

Base and mobile antennas,custom ball mounts, single, double, triple coil antennas, flat coils.

This page lets you do calculations for single layer air cored coils using the solenoid formula

Building coils for a portable dipole using a novel method of winding coils with weedeater cord! By K4MMG

An inverted V antenna for 40-80 with loading coils. This antenna is a full size on 40 and a shortened 80 by KG0ZZ.

A short dipole wire antenna for 40 meters band. It is a folded dipole that do not make use of coils and can be used either in horizontal or inverted V configuration

A 40/80 meters dipole made with two loading coils based on a project by IK1ZOY

Pictures of loading coils according to OK1FIG

Build an effective dipole antenna that needs much less space by adding two loading coils. This online calculator tells you how.

A multi-band portable vertical antenna can be built with relatively ordinary components obtained from the local hardware store, including replaceable loading coils

This page allows you to calculate in the most accurate way high-Q inductor coils.

Distributor of aluminum and a manufacturer of finished aluminum products. Pierce Aluminum offers a diverse inventory and distributes a complete line of sheets, coils, plates, bars, structural shapes, tubes, pipes and extrusions in the most varied alloys and sizes possible

Understanding current in loading coils

Tips on winding wire coils used as inductive loads, traps, band-pass filters, are implemented in a number of amateur radio projects especially antenna projects

Skin effect and proximity effect on making coils with stranded wire. An interesting comparison on making coils.

Communication Coil, Inc. designs and produces custom, high reliability Filter Networks, RF Coils, Chokes, Inductors, Baluns, Toroids and Power Magnetics for communications

winding coils for construction project

Maker of filters, oscillators, cristals Coils, Toroidal Inductions, Solenoids, Bifilar wound Solenoids, Trifilar Solenoids and Transformers Located in Kansas City, Missouri

Originally eveloped by I1FLC, uses seven plug in coils covering 3.0 to 30Mhz in a Colpitts oscillator circuit.

The Vertical Buddi Beam on 20m using no Coils. n this article I am going to describe a totally new way to construct and use a very old design the two element Yagi antenna. Unlike the traditional Yagi this design does not require a Tower or a boom, it is 100 percent portable and most important high- performance and easy to assemble using standard Buddipole components.

Manufacturer of transformers, inductors coils and chokes. Custom winding, EMI / RFI Filters, Antenna Windings on ferrite rod, Antenna Winding on phenolic. Any antenna coil designs.

Coil Q Measurements - With a special focus on wet coils.

While intended mainly for antenna loading coils, this article also applies to other resonant systems, such as amplifier tank circuits.

A very popular method of making a short dipoles resonate at a given frequency. This type of antenna is suitable for single band, narrow bandwidth use.

The program can be used to calculate inductors (coils) and their number of turns on ferrite cores, ferrite shells and air coils. These can be used for baluns, Ununs, bandpass filters, low pass filters, resonant circuits, and more. The technical specifications of the cores are already integrated in the program. Application is free and runs on Windows 32 bit versions only. To make it run on Windows 10 64 bit need to be unzipped in a single folder.

About experiments and measurements on loading coils using net standing wave current

The webpage discusses metal fatigue in antenna elements for radio amateurs, offering construction tips and techniques. It covers theory, tricks, and the use of baluns and coils.

Rewinding solenoid coils and how to article

A dual band dipole antenna for 40 and 80 meters band. Total lenght of 26 meters, foreseen two coils at aprox 11 meters distance from center feed.

A small antenna for 50 MHz made with copper cable loading coils

Repairing a Cushcraft R7000 antenna featuring several problems, mostly concerning coils and the insulating parts of the antenna.

Calculates inductance and Q for single-layer coils made of solid or Litz wire. Uses U.S. or metric dimensions. Can automatically maximize Q. Includes accuracy data. Runs in Windows.

Electronic Products Design Inc based in North Carolina, offers you custom design of transformers, coils, and telemetry control systems.

The "DIY Telescopic-V Antenna £35" project showcases the creation of a budget-friendly, portable telescopic V-shaped antenna inspired by commercial designs. Using eBay-sourced telescopic whips and custom mounting solutions, the author documents their process, testing, and adaptations. Despite challenges like weather and missing tools, the antenna performed well across multiple bands, enabling successful QSOs. Future improvements include exploring loading coils and testing in better locations. The compact design offers versatility for amateur radio enthusiasts seeking an affordable and practical solution.

Vertical Base Replacement Coil. Wolf River Coil build quality antenna coils that are easy to tune and easy to install.

This article describes the construction of a three-band vertical antenna for the WARC bands (10, 18, and 24.9 MHz). Unlike a previous design using thin wire requiring a complex matching device, this version uses a telescopic set of pipes, reducing reactances and simplifying the matching device to two coils and two capacitors. The article provides details on the antenna model, the matching device circuit, and tuning methods, including the use of frameless coils and variable capacitors. With proper tuning, the antenna achieves a VSWR not exceeding 1.3 across all bands, demonstrating a practical and efficient design for amateur radio enthusiasts.

One of the interesting features of the FT-817 is that many of the conventional calibration settings that would have, in the past, been done using manual adjustments of coils, capacitors, and potentiometers, are done via software.

An easy to build 6 watts SSB transceiver for 14MHz. BITX is an easily assembled transceiver for the beginner with very clean performance. Using ordinary electronic components and improvising where specific components like toroids are not available, It has a minimum number of coils to be wound.

Coil64 (Coil32) is a versatile tool for calculating single-layer inductance coils used in various electronics, such as matching circuits and amplifiers. The online calculator enables users to estimate the number of turns, winding dimensions, and select the appropriate wire type for home-brewed RF inductors. It employs Bob Weaver's equation, factoring in wire corrections, and allows for the calculation of Q-factor and self-capacitance. Coil64 is compatible across multiple platforms, including Windows, Linux, Mac-OS, and Android.

This PDF article introduces a series of dual-tuned bandpass filters designed for input tuning in amateur band receivers. Developed by Stefen Niewiadomski, these filters feature 50-ohm input/output impedance and can be cascaded for improved roll-off outside the passband. The designs use readily available TOKO coils, with taps on the tuned winding for matching input circuits with impedances around 1k ohm. The inductors are core-tuned, with average inductance values provided for easier matching to other inductors.

Learn how to build the PAC-12 Antenna, a multi-band portable vertical designed by long-time antenna aficionado James Bennett, KA5DVS. This award-winning antenna is easy to homebrew using common components from a hardware store, with replaceable loading coils. Perfect for hams looking for an efficient and portable antenna for field trips. Discover the design and construction plans, as well as the author's journey to create the ideal travel antenna for lightweight and packable use.

This document outlines the construction of a homebrew Buddipole antenna variant, designed for portable use and emergency services. The antenna utilizes telescoping whips and loading coils, enhancing its versatility across various HF bands. Key components include fiberglass rods, brass fittings, and Anderson Power Pole connectors, ensuring robust electrical connections. The design emphasizes non-inductive materials to minimize interference, while practical assembly techniques, such as epoxy and heat shrink tubing, are employed for durability. This variant aims to improve upon traditional Buddipole designs, offering greater strength and functionality.

Learn how to construct a balanced Antenna Tuning Unit (ATU) for your ham radio equipment. Follow the instructions provided by Bengt, SM6APQ, to create a variable capacitor insulated from the ground for additional safety. Discover how to set up the ATU for the 20 to 10m band with proper spacing between coils. Use low power when adjusting the ATU for lowest SWR. Avoid using switches and opt for banana plugs for flexible connections. Visit the Creative Science Centre website for more information and resources on ATU construction.

The LKJ Wednesday Night Special Antenna, designed by John Whiteman K5LKJ, is a compact 50-foot coil-loaded dipole for 80-meter operation, ideal for space-limited hams in residential areas. Using two 1-inch diameter PVC coils with 87 turns of #16 magnet wire each—placed 10 feet from the center—it tunes to 3.910 MHz for local nets like BVARC Rag Chew. Constructed with #14 wire, ceramic insulators, and Mini-8X feedline, it handles 1000W, performs well at low heights for NVIS, and requires a tuner for bandwidth. Collaborative tuning by club members ensured success.