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Wideband receiving phased arrays with small electric or magnetic active wideband elements are discussed in details. Practical results and examples are given.

Encouragement for Little Pistols, article originally written for and published in SKIP the monthly newsletter of the Fresno Amateur Radio Club

Performance data of the KIO Hexagonal Beam antenna

Adding a full power output 12 meter band capability to the Yaesu FL-2100 despite of 10 meter.

These are QRP rated 3 Pole Butterworth filters based on a design by K4VX, feature simplicity, almost no insertion loss, and reasonable rejection on the other ham bands.

An interesting presetnation full of usefull tricks to correctly design and build 23 cm Yagi using simple tools. The basic design of the antenna presented in this document is taken from the original DL6WU Yagi Design published in 1982

160 to 40 meters inverted L antennas projects

Add bands to your Hustler xBTV Series Vertical

Building an omnidirectionnal antenna for the 23 cm band

Band filters for PA6Z made by PA9M, designed by W3NQN.

An home made doblet antenna made with two Slinkys that are aproximately five meters in length connected with a twin-feed connected to a balanced ATU

A monoband delta loop antenna for the 7 MHz. This vertically polarized DX Antenna is a full wavelength sngle side antenna and has a total length of 42.3 meters (137,1 inch) Can be easily setup with a flag pole or fishing pole as center top mast. For optimal performance lower side should be at 2 meter above the ground. This antenna offers a low radiation angle and 1 DB Gain.

Homemade LC Bandpass Filters for 20M, 30M, 40M In multi-station environments like special events, field day, portable operating, is very important to protect receivers from excessively strong signals. Bandpass filters help to protect your transceivers.

Radioclub KAPA,OM7M Partizanske Slovack republic

A dipole can be broadbanded by a number of techniques including by matching with resonant sections of transmission feed lines.

Extending The Bandwidth of 80 Meter Dipoles

A technical explanation of what is a mesh node in HSMM-Mesh HamNet, with explaination of specific roles of each network interface

VK1OD informations on BPL

Wikipedia page on Notch filter, a narrow stopband - high Q factor filter

Amateur radio repeaters extend communication range for mobile and remote stations by retransmitting signals on a different frequency, often for emergency communications. The resource details various repeater bands, noting that 2 meters and 70 cm are primary for activity, with 10-meter repeaters offering potential national and overseas coverage. It specifies **18 channels** on 6 meters and **31 channels** on 2 meters, along with a new 70 cm offset of _7 MHz_ adopted in 2015. The content explains how repeaters can be linked via dedicated transmitters/receivers, landlines, or Internet VoIP systems like _IRLP_ and Echolink, enabling global connections. It also describes simplex gateways for multi-band operation and the use of CTCSS subaudible tones for access control and interference mitigation. The document highlights specialized repeaters for modes beyond voice, such as SSTV and ATV, particularly on 70cm and higher bands. Operational guidelines for efficient and courteous repeater use are referenced, along with links to Australian repeater listings and band plans.

A trapped multi band end-fed-half-wave antenna for 40/30/20/17/15m.

A summary of common calling frequency for each digital mode on that band.

An inverted V Dipole antenna for HF bands, working on 10 20 40 and 80 meters band. PDF Presentation

An introduction top operating on 160 meters band, article appeared on November 2006 issue of CQ, PDF file by K9LA

About antenna or aerial resonance and bandwidth and the impact of RF antenna resonance and bandwidth on radio communications systems.

This is a 30-watt sea level beacon intended for the coastal path between Northern and Southern California

Adapted from a similar project by NA4IT. Made with one quarter wave 2 meter radiating element pointing upward and it is surrounded by four 70 cm elements.

In this article the author shows the receiving loop antenna for 160 meters band installed at his QTH. Diagram and movie available. Article in in Turkish but can be translated in english

A travel, or a fixed vertical coax antenna originally designed by PA0FBK. This antenna is very easy to make from a piece of 50 ohm or 75 ohm coaxial cable, and can be either smooth, roll-up version, or rigid cable

The Homebase-10 is a wire halo antenna for 10m built with DIY store parts, effective despite its small size. Includes a dual-band version for 10m and 6m with gain around 0 to -2dBd, near omnidirectional pattern, and horizontal polarization. Overview based on a 2008 Practical Wireless article.

Summit Prowler 6 is a pocket-sized SSB/CW transceiver for 80, 40, 30 and 20m

IARU Regional bandplans

A multi band antenna for HF band capable to operate from 10 to 80 meters band depending on wire lenght loaded with a small inductance neat the feed end.

The equipment shown on this page comprises a basic G3WDG transmit and receive system with the addition of a 1W Qualcomm amplifier.

A homebrew radio transmitter project, based and inspired by the original 30 Watts input on 80 50 and 15 meters band transmitter by W11CP

A review of the HF ham radio bands, considere by far the most popular bands in the amateur service. HF bands offer local QSOs and world-wide propagation are all possible at almost anytime with careful selection of the right frequency for the time of day, time of year, and current state of the sunspot cycle.

This simple antenna was installed on the attic. Antenna was matched with help an Automatic ATU in 40, 30, 20, 17, 15, 12 and 10 meter amateur Bands. The Antenna worked satisfactory on the above mentioned bands.

Diamond W8010 Multiband Dipole Modifications

A trap antenna dipole covering two differen bands made reusing an old 160/80m inverted vee antenna.

Sort of similar to the one of the 6m omni. Instead of using twin-lead, this design makes use of a more or less regular double bazooka antenna (coaxial dipole). Your attention shall be drawn to the available standart literature, such as Rothammel. In order to "compute" the dimension, Karl Rothammel mentioned that the total length of the dipole shall be 95% of the free-space wavelength. The short-circuit bridges (closing the folded dipole) are to be placed at a distance-fraction being equal to the velocity factor of the coax cable used, which will be 66% using RG-58 or RG174.

A 70 MHz Transverter project with a block diagram and schematics

A loop antenna for 80 and 40 meters band, the main loop is based by a crossed line using aluminium strip lines. The main loop diameter is 150 cm.

A modified Hairpin antenna for a wider bandwidth an mounted on a grounded metalic mast

NEC models are used to explore the GR5V and ZS8BKW optimizations. A third optimization is also rediscovered. The effect of fixed lengths of 75 ohm coax are explored. A link to the NEC model is provided.

About keying speed affecting occupied bandwidth of a transmitter.

Active Receiving Antennas, designed for reception of shortwave, mediumwave and longwave signals and VHF/UHF signals

This amplifier takes advantage of the proliferation of surplus cellular 26v RF boards

How to build a complete Single-Sideband amateur radio transceiver from scratch. Article published on hackaday dot com includes an introduction to radio architectures, ssb receivers and tramsitter

Microwave band plan - frequancy assigned to ham radio service

How much bandwidth does it take to send Morse code? by Mark Amos, W8XR