cavity coils

DL9MEU Antenna projects - 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.

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.

Rotatable Dipoles  ^pop - Portable, and shortened with loading coils rotatable dipoles for 6 meters, 20 meters and multibands.

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

Current distribution in Coils - Current distribution in the antenna loading coils

Loading Coil for 136 kHz - Pictures of loading coils according to OK1FIG

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

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

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

A $20 HF mobile antenna - A few hours of fun with PVC and wire and you’ve 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.

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

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

Link Coupled Tuner - Legal Limit Link Coupled Balanced Tuner,for the amateur ham radio HF bands. This Tuner uses plug-in Coils sets for 40, 80, & 160 meters

TX RX Systems Inc - TX RX Systems Inc. manufactures signal boosters, rf antennas, transmitter combiners, cell enhancers, land mobile radios, duplexers, receiver multicouplers, bidirectional amplifiers, bda, rf amplifiers, rf filters, rf cavity filters, rf combiners, rf components, in building rf coverage, repeaters, repeater amplifiers, rf management equipment, rf systems, and rf solutions. TX RX Delivers Reliable Solutions.

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

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

Hi-Q Antennas - HF Ham Radio mobile operation antennas manufacturer, W6HIQ, HA5CMG, VE7BOC, HF mobile antennas, screwdriver antenna, coils and filters.

Barker & Williamson - Dipole antennas, unique broadband antennas, trap dipole antennas, coils, accessories for HF radio

Circuit Specialists - We specialize in pc-based data acquisition systems, test equipment, electronic components, disk on modules, choke and coils, diodes, capacitors and connectors, potentiometers, crystals, resistors, relays

WINRLC - Simple freeware tool to calculate several kinds of HF filters. Use to calculate L-C and R-C band filters and bandpasses, L-C, L-R and R-C highpasses and lowpasses, coils and capacitors.

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

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

A 80/40m DDS controlled QRP CW transmitter - JUMA-TX1 is a 5W CW transmitter for the 80/40m bands. Juha (OH2NLT) and Matti (OH7SV) have had high quality CW keying and a compact size as design goals for this project. No coils need to be wound to construct this transmitter!

A 80/40m Direct Conversion HF Receiver with DDS VFO - Juha (OH2NLT) and Matti (OH7SV) have designed JUMA-RX1, an award winning 80/40m direct conversion HF receiver with highly accurate direct digital synthesis VFO. The receiver is very compact, because it constructed using surface mount components. No coils need to be wound to construct this receiver!