coil

Petlowany Antennas by K6NO - 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

Building High Power, High Q, Loading Coils - This page describes the loading coil (inductor) that W8WWV built for my center-loaded 160 meter (1.83 MHz) vertical antenna.

40 meter shortened dipole - M0MCX - Interesting little project with a couple of loading coils by M0MCX

Coil loaded dipole for 80 meters - Coil loading of an 80m Dipole for restricted space. Here's a method that may allow you to fit that 80m dipole into your suburban backyard by VK3JEG

Coil calculator - On-line single-layer coil designer

Antenna Loading Coil Construction Techniques - This page explains how to construct high-Q inductor coils.

Build Your Own Coils - A method of building coils for your home made antennas

Home Brew Loading Coil for AD5X Vertical - How to make a loading coil for the AD5X portable vertical antenna

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

Single Coil Z Match - Single Coil Z Match, circuit Diagram and homebrewing notes

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

An automatically tuned 7-30MHz mobile antenna - 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.

QRP Antenna 80-40-20-15 End Fed Antenna - A long wire antenna that will load up on 80, 40, 20 & 15 meters without an antenna tuner and without balun coils

Base Loaded 160M Half-Sloper Antenna - If you want an antenna resonoant on the 160 meters band this is a possible solution, but of course, need space.

Currents in Standing-Wave Antennas - How can the current "flowing" out of the top of a mobile loading coil be greater than the current "flowing" into the bottom of the coil?

CoaxTrap - This program let you design of antenna trap using length of coaxial line wound as solenoid on a coil former.

Single Coil Z Match - The simple Z match tuner simplified, article by Lloyd Butler VK5BR

The Alabama Historical Radio Society - The alabama historical radio society - come visit our website and museum where we have a large collection of antique radios. our club does coil winding, has a large library, and a wealth of knowledge in our members.

Pierce Aluminum - 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

TANT 136 - DOS program for calculating the performance of a T antenna. Gives loading coil info and matching plus ERP by Reg G4FGQ

WEController - This software let you to control a pair of stepper motors, for three principle jobs: coil tuner, manual tuner control and satellite rotor control

HeliCoil - Inductance calculation for single layer, air-wounded coils and helixes up to about 800 MHz. Inductance calculations accuracy is around 1%. Also, coils with maximum Q for given inductance, resonant RF chokes, PI and T resistive attenuators calculations are provided. Skin effects, radiation losses and other minor side effects are not accounted in maksimum Q factor coils calculations. Program assumes using copper (Cu) enameled or silver (Ag) plated wire. Program is writen bilingual in English and Serbian by YU1AW

Online Calculators for Radio & Electronic Design - Online calculators for toroid coil, air-core coil inductance, XL, XC, and more.

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

A good regenerative receiver - A good SSB-CW-AM regenerative receiver with a fine tuning by moving the wooden stick with a grounded piece of PCB towards the coil.