# Theory

## Basic antenna theory

### Home : Antennas : Theory : Page 4

 Antenna Gain (30) Impedance matching (27) Wind Load (6)
• Matching Waves, VSWR at work - When the radiation resistance (voltage to current ratio) of an antenna is the same value as the characteristic impedance of the transmission line (voltage to current ratio in the line), all of the electrical energy transmitted down the line is taken by the antenna and radiated into space in the form of a radio wave.
[ Hits: 413 | Votes: 0 | Rating: 0.00 ]
• Maximum Usable Angle - We are all familiar with Maximum usable frequency. Maximum usable angle is the other half of the maximum usable frequency equation.
[ Hits: 142 | Votes: 1 | Rating: 10.00 ]
• Measuring 2.4 GHz Helix Antennas - It is not very difficult to design and make a helix antenna for a specific frequency and gain. It is more difficult for the serious experimenter to make precise measurements of the finished antenna.
[ Hits: 154 | Votes: 0 | Rating: 0.00 ]
• Measuring Antenna System SWR - Have you measured the SWR at the antenna?
[ Hits: 201 | Votes: 1 | Rating: 10.00 ]
• Measuring Cable Loss - Improving measurement accuracy when low-power analyzers are used.
[ Hits: 633 | Votes: 2 | Rating: 7.50 ]
• Mini-Beam Geometry Basics - There is a natural progression of the geometry of the "mini-beams" deriving from the basic yagi, which in itself owes a lot to the common dipole. By Dick Stevens, N1RCT
[ Hits: 412 | Votes: 1 | Rating: 1.00 ]
• More Information on the EH Antenna - How EH antennas works and how it has performed.
[ Hits: 2122 | Votes: 1 | Rating: 5.00 ]
• Multiband trap antennas - Detailed analysis of multiband trapped antennas with references on efficiency, height above the ground, feed lines and total length
[ Hits: 390 | Votes: 0 | Rating: 0.00 ]
• No Tuner Antenna System - Article on resonant antennas systems by KA3MRX
[ Hits: 310 | Votes: 1 | Rating: 7.00 ]
• NVIS Propagation concept - Army Field Manual 24-18 Appendix M with Graphics
[ Hits: 2790 | Votes: 12 | Rating: 8.92 ]
• Optimizing Inductors - While intended mainly for antenna loading coils, this article also applies to other resonant systems, such as amplifier tank circuits.
[ Hits: 446 | Votes: 1 | Rating: 10.00 ]
• Passive antenna re-radiators - Passive Antenna Re-radiators to function as Q Multipliers
[ Hits: 299 | Votes: 1 | Rating: 5.00 ]
• Phasing of two identical antennas - Phased Spaced Active Whips and Broadband Loops by WA1ION
[ Hits: 320 | Votes: 0 | Rating: 0.00 ]
• Phasing Systems - Antennas, Standard Delay Line Systems, Crossfire Phasing or Hybrids
[ Hits: 757 | Votes: 2 | Rating: 3.00 ]
• Polarization, lines of force - While polarisation may seem insignificant compared with other considerations in setting up a communications system, choosing the right type can make significant improvement in performance.
[ Hits: 429 | Votes: 0 | Rating: 0.00 ]
• Portable antenna comparison - Common antennas for portable use compared. A vertical antenna, a dipole antenna an inverted V and a fan dipole all at same height.
[ Hits: 669 | Votes: 0 | Rating: 0.00 ]
• QEX Ground System Experiments - N6LF series of experiments on ground systems for vertical antennas. That series of reports was converted, with some modifications, into a series fo seven articles in QEX magazine.
[ Hits: 599 | Votes: 1 | Rating: 8.00 ]
• Quad or Loop antenna - Information about quad and loop antennas, matching tips, differences on polarization and impedence by PA0FRI
[ Hits: 815 | Votes: 3 | Rating: 4.33 ]
• Quarter Wave Verticals - One of the most useful antennas in the repertoire is the Marconi or quarter wave grounded vertical antenna. Its invention made it possible to halve the length of antennas, simplifying communications, especially at HF and below.
[ Hits: 1635 | Votes: 2 | Rating: 7.00 ]
• Quarter Waves and Velocity Factor - Coax Velocity Factor in Baluns, Does it Matter? Test results show coaxial cable velocity factor does not always enter into stub length calculations especially in the world of Baluns
[ Hits: 111 | Votes: 0 | Rating: 0.00 ]
• Radial System Design - Are the lengths of antenna radials related to the height of a vertical? By N6LF
[ Hits: 718 | Votes: 1 | Rating: 5.00 ]
• Radial systems and ground - Radial systems for elevated and ground mounted vertical antennas by SteppIR
[ Hits: 2053 | Votes: 4 | Rating: 8.25 ]
• Radiation and fields - Electric Fields, magnetic fields, electromagnetic fields, losses, fresnel zone, nearfield and farfield
[ Hits: 372 | Votes: 1 | Rating: 10.00 ]
• Radiation and scattering - Basic antenna theory, Antenna directivity and effective area, Antenna arrays
[ Hits: 2967 | Votes: 2 | Rating: 10.00 ]
• Radiation Characteristics - Tailoring Patterns for HF Verticals
[ Hits: 163 | Votes: 0 | Rating: 0.00 ]
• Radio - The Easy Way - PDF article on Antenna of non resonant lenght, line attenuation, the transmatch, baluns by WB5IIR
[ Hits: 245 | Votes: 0 | Rating: 0.00 ]
• 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
[ Hits: 6266 | Votes: 6 | Rating: 6.33 ]
• Receiving Loop Theory - N4YWK - Sensitivity of multi turn receiving loops William E. Payne, N4YWK
[ Hits: 615 | Votes: 1 | Rating: 1.00 ]
• Restricted Space Antennas Notes - W5ALT Antenna notes for a dummy dedicated to restricted space antennas
[ Hits: 620 | Votes: 1 | Rating: 5.00 ]
• RF Measurement on W3EDP antenna - RF Current measurements on a Long Wire W3EDP antenna
[ Hits: 422 | Votes: 1 | Rating: 1.00 ]
• RMS power - How it's misused and misunderstood, and why it's not useful.
[ Hits: 505 | Votes: 3 | Rating: 6.67 ]
• Secrets Of Getting a Vertical To Work - Or how I overcame the old saw, a vertical radiates equally poorly in all directions
[ Hits: 428 | Votes: 0 | Rating: 0.00 ]
• Selecting a Multi-Band Vertical - Choosing a vertical antenna. Buying guide to amateur radio HF vertical antennas by Bencher inc
[ Hits: 1379 | Votes: 0 | Rating: 0.00 ]
• Sensitivity of Multi Turn Receiving Loops - Magnetism is manifested as a 'field of vectors', that is, any point in the magnetic field has not only a magnitude, but a direction in space. The four Maxwell equations describe how electric and magnetic vector fields behave and interact.
[ Hits: 265 | Votes: 0 | Rating: 0.00 ]
• Single-stub matching - Single-stub matching of transmission lines to loads A worked example
[ Hits: 426 | Votes: 6 | Rating: 4.00 ]
• Sloper Antenna Tests - Mark Connelly - WA1ION tests on slooper antennas
[ Hits: 2970 | Votes: 1 | Rating: 2.00 ]
• Small antennas and radiation resistance - Small antenna, what causes loss and how to increase radiation resistance in small antennas., A description of loss and radiation resistance.
[ Hits: 783 | Votes: 0 | Rating: 0.00 ]
• Small High-Efficiency Loops - Article about small loop antennas by W5QJR published on QST 6-86
[ Hits: 360 | Votes: 0 | Rating: 0.00 ]
• Smart Antennas Tutorial - Smart antennas or the adaptive antenna array and smart antenna technology used with SDR, cognitive radio, MIMO, and other new technologies.
[ Hits: 359 | Votes: 0 | Rating: 0.00 ]
• Smith Chart Basics - Smith Chart it is a graphic tool for solving transmission lines problems
[ Hits: 228 | Votes: 1 | Rating: 10.00 ]
• Some plain facts about multiband vertical antennas - There is considerable confusion as to what exactly a multiband vertical antenna is. The confusion concerns the method of feed, how much mismatch one can expect, how many radials are required, how the particular antenna is built for multiband use, plus some other points.
[ Hits: 1741 | Votes: 1 | Rating: 7.00 ]
• Speedometers SWR Meters and Smith Charts - Have wondered why a Smith chart has such strange grid lines. Believe it or not, there is a logical progression from Speedometers to Smith charts that will make the Smith grid crystal clear.
[ Hits: 372 | Votes: 1 | Rating: 5.00 ]
• Stacking for 50MHz - Summary of discussion on stacking antennas on six meter band
[ Hits: 1076 | Votes: 1 | Rating: 10.00 ]
• Stacking yagis on a single tower - How to stack different band yagi antenna in a single tower
[ Hits: 194 | Votes: 0 | Rating: 0.00 ]
• Stealth Attic Antennas for DX and Contesting? - Considerations on using attic antennas for dx anc contesting operations.
[ Hits: 278 | Votes: 1 | Rating: 8.00 ]

• Search dxzone.com on Antenna
• Lookup Google Custom Search Engine for Antenna
• Search Antenna with: Yahoo!, Bing
• #### Antennas

Search only in "Theory"

#### Antennas : Theory

The DXZone is the largest human created and maintained library of web sites dedicated to Amateur Radio, currently lists 20.000+ links organized into 600+ categories and subcategories. Ham Radio operators review new sites every day since 1998, for potential inclusion in the Directory, and to evaluate the best place to list them.