Theory

Antenna basics - Basics by From Ian C. Purdie, VK2TIP

Balun Theory - The word balun means balanced-unbalanced: it's used to adapt a balanced device to an unbalanced one

J-Pole theory - The J-Pole antenna is an omnidirectional antenna that can be used for base, mobile and field day stations. It does not need a ground plane, radials or a complicated matching system. The J-Pole can be cheaply, simply and quickly constructed using a variety of techniques, some of which are discussed in this article.

Antennas basics - An antenna study guide by NZART, cover basic topics like dipoles, wave lenght calculation, baluns, beams, dummy loads, and measurements.

Install a PL-259 on an RG-8X - A better way to install PL-259 connectors on RG-8X type coax by Dan Richardson, K6MHE

Basic Antenna Theory - Basic antenna theory by sub-TV

Antennas and Grounds for apartments - Suggestions on finding RF ground when you live in an apartment and you want to setup an antenna

Do You Need an Antenna Tuner - Maybe yes, maybe no. It all depends on the type of antenna and feed line you're using. QST Article in pdf format

Dipole Height - How High should my Dipole be? Dipole Antennas and the effect of height above ground

Why an Antenna Radiates - How antenna works by ARRL

Grounding system - Perhaps one of the most over looked aspects of setting up a listening post is a ground system

How to Construct a Dipole - Basic and illustrated article on building wire dipole antennas. This page is about "how to build a dipole antenna"

FAQs - Basic Antenna Theory - Faqs and antenna basics

Types of multiband antennas - Types of multi-band antennas for the HF bands, from the horizontal end fed wire, to g5rv, log periodics, trap dipoles, vee beams and rhombic antennas.

Antennas : theory and designs - Thierry LOMBRY, ON4SKY, develops in several long articles all you need to know about antennas, their design and performance, for both amateurs and SWL

W1GHZ Microwave Antenna Book - The W1GHZ Online Microwave Antenna Book online

Understanding Standing Wave Ratios SWR - We worry a lot about Standing Wave Ratio (SWR) in amateur radio since SWR is one indication of how well our antenna system is working. Most HF transceivers and antenna tuners have built in SWR meters. SWR is a measure of a transceiver’s output power verses the portion of that power reflected by the antenna system By Ken Larson KJ6RZ

Low Noise Antenna Connection - Reducing noise to your antenna can gain your aerial performance, learn how.

Antenna Noise and Signal Cancelling at LF - By using the signals from two antennas, controlling their relative amplitudes and controlling the phase of one of them, unwanted signal or unwanted noise can be phased out. Circuitry is described which uses the signal from a wire antenna to provide selective cancelling against the signal output from an LF loop antenna.

G5RV Measurements - Measurements and characteristics of a G5RV Antenna, including effect of the transmission line as part of the antenna and contributes in a large way to it's multi band characteristics

Amateur Radio Antennas: Ground Theory - Perfect ground vs. poor ground. What is the difference? How does the ground influence the DX-gain?

Antenna & Mounts - Mobile antennas, how to install antennas in the roof of a vehicle and how tune antennas.

Rainbow Antenna Analyzer - A small and inexpensive measurement device designed to determine antenna performance across the amateur bands through use of automatically collected SWR readings

Using Delta Matching on HF Beams - Using delta match with HF antennas design

Dipole Calculation - Determining your proper length for the open half-wave dipole antenna

The Quarter Wave Sloper or the Inverted-V Dipole - A question that seems to be asked nearly everyday is, which is best, the quarter wave sloper or the inverted-V dipole? PDF File by AD communications.

HF antenna for high rise dwellers - If you have ever tried transmitting on HF from a tall block of apartments, where it's just not possible to erect a substantial aerial system, then this article is for you by Mel G4WYW

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

Coax velocity factor - Coax Cables velocity factor article in pdf format

Directional arrays - About collinear array antennas

Actual Antenna SWR - 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.

To Trap or Not to Trap - An interesting article on traps, pros and cons of trapping by W4RNL

Marine corps antenna handbook - U.S. Marine Corps in PDF format

Another way to look at vertical antennas - What iss the difference between a dipole and a vertical? Maybe not as much as you think. Come along and try another point of view.

The DK7ZB-Match for Yagis - Simple, easy to built match developed in 1995 for Yagis with resistitive loads of 12.5, 18 and 28 Ohm.

Antenna Transmatch Tips - Tips on tuning antennas using Antenna Tuning Units also called ATU. This article explains the functions and ills of tuners, along with some guide- lines for building an ATU.

Radiation and scattering - Basic antenna theory, Antenna directivity and effective area, Antenna arrays

Trap antennas, coaxial trap, coax dipole antenna loss resistance - Testing and comparison of traps and trap antennas

Vertical plane antennas' beaming comparision - Animated quad and yagi comparison. You can see antennas' characteristics behavior in a vertical plane with changing of the height.

Low reactance multiband center feed wires - An antenna system is more easily interfaced to a radio when the input reactance at the feedline terminals is low or close to series resonance

Coaxial cable dipole for 80m - Here are some simple antennas you can build along with calculators to help you get the right length.

50MHz Power Splitters - Splitting an antenna between two receivers or in use as the phasing harness in stacked antennas where there is a need to equally split the power from the transmitter between two antennas

Antennas for 100 Pound DXpeditions - NE1RD interesting publication published online about homebrewing antennas for dx peditions or portable use

Antennas for MF and LF - Long Waves, Short Antennas, designing antennas for MF and LF communications

Antennas: dirty little secrets I - Butternut article on calculating real efficiecy of commercial antennas

Azimuth Radiation Patterns - Below VHF the change in the radiation characteristics of an antenna will change considerably from frequency to frequency, making antenna selection more complicated.

Basics of antennas - The current, the voltage, the impedance, the bandwidth, the polarization, and how the earth influences the famous radiation pattern.

Better Feedline Loss Measurements with Antenna Analyzers - Various publications through the years have shown how the SWR measured on a shorted (or open) feed line can be used to calculate feed line attenuation

Cebik.org - W4RNL historic web site - A free historic mirror site of L. B. Cebik's W4RNL web legacy.

Choosing an Antenna - Choosing the right antenna for you, by Lewis G. McCoy W1ICP

Choosing and Antenna - Beginner guide on choosing an antenna for your ham radio station by W5RH

Choosing Wire Size for Toroidal Inductors - Measurements that show it doesn't make much difference

Coax Antennas - Amateur Radio Coaxial Antennas by G3TXQ

Coax Cable Loss - Table representing loss of Coax Cables in db per 100ft.

Coax velocity factor - Coax Cables velocity factor article in pdf format

Coaxial antennas - G3TXQ study on coaxial cable demonstrate that it can reduce an element's length by something approaching the Velocity Factor of the cable

Coaxial cable dipole for 80m - Here are some simple antennas you can build along with calculators to help you get the right length.

Coaxial Transmitting Chokes - Understanding Common Mode and Differential Mode Currents on Transmission Lines by K9YC

Common-Mode Noise - Receiving Common Mode Noise shows how lack of a balun can contribute to system noise

Conductors for HF Antennas - Putting up an antenna for the low bands? What kind of wire will you use? This analysis may change your plans.

Construction Principles for UHF VHF Yagis - The Construction Principles for Duoband-Yagis 2m/70cm by DK7ZB

Cubical Quad Antenna - Let's explore the cubical quad antenna, or quad, and see what it really is and how it really works by w8ji

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?

Designing Driven Elements in Yagi antennas - The design and feeding of driven elements for VHF/UHF Yagi antennas , modeling, observations and some case studies by Graham Daubney F/G8MBI

Dipole Antenna Radiation Patterns - Much confusion exists about the radiation patterns of antennas. In particular, the horizontal dipole is misunderstood by most who use it.

Dipole Calculation - Determining your proper length for the open half-wave dipole antenna

Dipoles versus Verticals - One of the classic arguments in amateur radio is whether a dipole or vertical is the best antenna

Directional arrays - About collinear array antennas

DXpedition Antennas for salt water locations - Which is better a 20m antenna for an island DXpedition: Yagi at 25', or a vertical or two on the beach?

Earth Systems - In order to resonate at a particular frequency, an antenna needs to be at least one half wave length long. Antennas below a 1/2 wave are dependent on a ground system for resonance as well.

Easy way antenna systems - Written by John M. Haerle, WB5IIR (SK). A must read for anyone considering building a good low cost HF multi-band antenna system.

Effects of Very Large Ground Screens - A theoretical and experimental study of the effects of very large ground screens on 20 meter verticals

Effects of VSWR on Transmitted Power - By James G. Lee, W6VAT

Errante's capacitive RF Grounding - This system demonstrates that no galvanic coupling to earth is needed for a proper RF earth grounding

Exploring the secrets of the Smith chart - If you're a Radio Engineer wannabee, you need to understand transmission lines. It's impossible to really understand transmitters and antennas without understanding lines. Using the Smith chart is far easier than really understanding the math by Chris Scott and associates

EZNEC simulation files - EZNEC Simulation files collection by DF9CY

FAQs - Basic Antenna Theory - Faqs and antenna basics

Feeder Radiation - Connecting centre fed antennas, dipoles, yagis, rhombics, loops to coaxial cable, unless care is taken, it is not difficult to end up with feeder radiation resulting in power loss and the radiation characteristics changes

Fiber Glass Rods and Tubes - Properties of fiber glass rods and tubes

Five eighths wavelength vertical antenna - The basics of a five eigths wavelength vertical antenna, a form of RF antenna widely used for mobile radio communications applications

From Transmitter to Antenna - A collection of articles on the subject of impedance, impedance matching and high-frequency power transmission by G3YNH

G0KSC Revolutionary Yagi Antenna Feed System - New feed system for the Yagi directional beam antenna, that suppress unwanted side lobes within longer Yagi designs by G0KSC

G5RV Measurements - Measurements and characteristics of a G5RV Antenna, including effect of the transmission line as part of the antenna and contributes in a large way to it's multi band characteristics

Ground / Radial Systems - Guide to ground mounting antennas by Bencher

Ground Problems - Collection of articles about ground systems

Grounding system - Perhaps one of the most over looked aspects of setting up a listening post is a ground system

Groundplane Antennas at Various Heights - Mounting on Roof or at Ground Level?

Harmonic Operation of OCFs - Theory - Up, Up, and Away or Harmonic Operation of OCFs

HF Antenna Coupling Techniques - Look at some of the various ways in which power can be delivered from a transmitter to a radiating system

HF antenna for high rise dwellers - If you have ever tried transmitting on HF from a tall block of apartments, where it's just not possible to erect a substantial aerial system, then this article is for you by Mel G4WYW

HF Antennas 101 - Here are 10 tips and truisms that every ham should know about antennas, by W20QI

HF insulation, the pitfalls - Although insulation may seem relatively insignificant in the larger picture, on it depends the quality of your performance on air and how long you will be communicating for.