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Monitoring shortwave broadcast stations effectively requires accurate schedule information to identify transmissions. This online utility offers a straightforward, graphical interface designed to search for and display current shortwave radio broadcasting schedules. Users can precisely filter results by frequency, specific language, broadcaster, time of day, and even by shortwave band, which simplifies the process of pinpointing desired content. The database, last updated on March 26, 2023, details station callsigns (e.g., BBC), start and end times in UTC, days of the week, broadcast language, transmitter power in kilowatts, and azimuth. Crucially, it includes the precise geographical coordinates of transmitter sites, such as Woofferton in the UK or Al Seela in Oman. This data is invaluable for predicting signal paths and optimizing antenna direction for improved reception, a key consideration for serious SWLs. For instance, a search for BBC English broadcasts at 21:04 GMT quickly reveals multiple active frequencies like 17780 kHz from Woofferton, offering a clear overview of current transmissions. The tool processes queries rapidly, returning results within seconds, demonstrating its efficiency for broadcast listening enthusiasts seeking timely information.

Here is a 70cm (440 Mhz) J-Pole antenna that is inexpensive, and easy to build. Author use 1/2 inch copper pipe, and the associated fittings necessary. The dimensions aren't typical however, this is what it took to get its SWR low.

What is a dipole antenna and why are they so popular ? Arrl PDF file

Baluns what do they do, in a pdf file by W7EL

DIY Basic Electronic Theory, Basic Antenna Theory with Antennas built from common materials. What does SWR really mean. Baluns from transmission line.

What is the best balcony antenna? what antenna would you recommend for use on typical hotel balcony? Read some answers here

Perfect ground vs. poor ground. What is the difference? How does the ground influence the DX-gain?

Freeware antenna software that lets you see what the polar diagram of your rotatable beam actually looks like where it is operating. With PolarPlot you can measure the polar diagram of the antenna and check for abnormalities - compare plots taken before and after changes to the design or location - check the -3dB beamwidth - look at the front to back ratio - see the size and position of the sidelobes.

What is NVIS Near Vertical Incident Skywave. This article on NVIS (Near Vertical Incidence Skywave) explores its role in short-range HF communication, covering 0-200 miles. NVIS utilizes antennas with high radiation angles and frequencies below the ionospheric critical frequency to achieve reliable local contact. He details optimal antennas, like low dipoles, and practical tips for maximizing NVIS performance, emphasizing its advantages such as reduced noise and independent operation without repeaters. However, challenges include frequency sensitivity and the need for appropriate antenna setups at both ends for effective communication.

What is the best WiFi antenna for me? Looking for a range extender antenna for your WiFi system. This article will help in choosing the correct antenna for your system

An interesting article on NVIS antennas, explaining basics of NVIS antennas and the main usage of this particular aerials by Patricia Gibbons

This Field Day Vertical Antenna project is the result of many years of attending various field day sites and realizing that what was needed is a simple, easy to assemble vertical antenna.

What type of antenna should I get? Well, the best type of antenna for working the OSCAR satellites are circular polarized antennas

What You Should Know About Lightning Protection by Joseph H. Reisert

The Q-signal **QRP** signifies a request to reduce power, and in amateur radio, it defines operating with 5 watts or less for CW and 10 watts or less for SSB. This article addresses common inquiries from new hams regarding the practice, its benefits, and implementation methods. It explains how a 5-watt QRP signal, compared to a 100-watt signal, typically results in only a 13dB drop in signal strength, equating to about two S-units, still providing solid copy under most conditions. Hams choose QRP for various reasons, including seeking a greater challenge in DXing or contesting, reducing band interference, or enabling portable field operations with lightweight, battery-efficient equipment. A modern single-band CW transceiver, key, and antenna can fit into a pocket, offering receiver performance comparable to commercial rigs and extended operation on a small battery. This portability facilitates operations in remote locations where higher-power setups are impractical. Operating QRP can involve simply reducing power on an existing commercial HF rig or building a dedicated QRP transceiver from a kit, such as the **Wilderness Radio SST** with its 2-watt output and 15mA receive current draw. While SSB is viable, CW remains the most popular and efficient mode for QRP due to its superior signal-to-noise ratio. The article lists common QRP calling frequencies across 160m through 10m bands for both CW and SSB, and highlights organizations like QRP ARCI and NorCal that support the QRP community.

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.

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

Some antenna manufacturers place baluns at the incorrect location in LPDA arrays. If we consider what the balun does we can see how the mistake occurs.

The basics of what is a discone antenna for wide band or bandwidth omnidirectional applications.

Optimizing a G5RV or ZS6BKW multiband wire antenna for HF operation often involves addressing common SWR issues and understanding feedline characteristics. This resource chronicles the construction and performance evaluation of a G5RV, initially built for 80m, 40m, 15m, and 10m bands, by a newly licensed Foundation operator. The author details the selection of materials, including 3.5 mm stainless steel wire for the doublet arms and enameled copper wire for the open-wire feeder, and the initial decision to omit a balun based on common online information. The narrative highlights the initial disappointing performance, characterized by high receive noise and poor signal reports on 80 meters, despite the transceiver's internal ATU achieving a 1:1 match. This led to experimentation with a coax current balun and further research into G5RV myths, such as SWR claims and the necessity of a balun. The author then describes modifying the antenna to the ZS6BKW configuration, which involves specific changes to the doublet and feedline lengths, and integrating a 1:1 current balun wound on a ferrite toroid. The modifications resulted in improved reception and transmit performance across the bands.

Article on mobile antenna mounting methods by Firestik

What is an EWE Antenna, comparisons, performance and homebrew plan

A very interesting blog article on a real world comparison on the popular multiband wire antenna, the G5RV, by Bob Raynor N4JTE

Most people are not familiar with antenna tuners and what a antenna tuner actually does.

General article on Baluns at myantennas.com, what is a balun and when to use baluns

About the basics of what is a discone antenna for wide band or bandwidth omnidirectional applications

Small antenna, what causes loss and how to increase radiation resistance in small antennas., A description of loss and radiation resistance.

Hams have been putting stations in their cars since the Twenties. Today, there is great satisfaction in facing the challenge of installing a transceiver in our small cars and pick-ups, using somewhat inefficient antennas

May 2015 Radcom Article on common-mode chokes that can be used for control cables, phone lines, but mostly on typical HF antenna systems. This article explain what common mode chokes does, why you meay need one, properties common mode chokes should have, how to build and measure performances.

Antenna modeling discussions about What happens if... a dipole is bent horizontally, laterally, vertically. Zig-zag, meander, catenary curve. Effect of sag, elevation, radials. OCF off-center feed, harmonics. Includes 4NEC2 antenna models for each study.

Wondering whether to spend a fine day with the YL or with the antenna? This article may help you decide by W1GV

It is not always possible to tackle the sources of local QRM. What remains is trying to reduce the noise level by means of your antenna system. Learn how to reduce QRM and understand how cancell noises.

Article provides a guide on how to use 24 GHz band and what to expect, including Active modes, equipment, propagation and antennas for this band in by VE3SMA

Summary, tutorial about the basics of what is a waveguide and the basic waveguide theory.

An article that explain with simple concepts and basic theory the correct usage of antenna tuners. It covers some aspects of common questions newcomers have on what antenna tuners are for, and what antenna tuners will never do.

A six meter band 3 element yagi beam antenna project with shortened elements using coax cables with the outer ends stripped and the center conductor shorted in somewhat of a Bazooka antenna.

No exotic claims are made for this antenna. Author just tried a few WSPR experiments on 40 meters and was surprised with the results. What appears below may inspire you to try something equally off-the-wall, to see what happens.

What is the smallest dish for serious 23cm CW EME operation?

Available worldwide can be used as Arduino Shield or plug it in to you PC , or with a bluetooth adapter connect to Android. With a highly optimized software, KAI200 brings you: a. Antenna analyzer form 1 up to 200 Mhz; b. WSPR transmiter (set up by serial terminal); c. Square Wave Signal generator KAI200 is all you need for your radio whatever it is Yaesu, Icom, Kenwood or Drake and DIY projects.

One of the featured products, the V350 CAMP, is a multiband vertical antenna covering 6 to 80 meters, priced at R$ 799,90, demonstrating the range of ready-to-use solutions available. The inventory includes various antenna types such as **HF**, **VHF**, and **UHF** designs, along with dual-band options like the J-Pole Dual V/UHF for R$ 235,00. For those building their own arrays, the store stocks essential components like element holders, clamps, junction boxes, and aluminum plates, alongside specialized items such as the KIT Isolador Central Dipolo - 01DX for R$ 99,90. The shop also provides a comprehensive selection of installation hardware, including diverse antenna mounts, PTT supports, and various coaxial cables like RG58 and RG213, with prices up to R$ 849,90 for RG213. Connectors such as UHF male PL259 and various adapters are readily available, ensuring compatibility for different setups. Additionally, specialized items like side handles for popular transceivers such as the FT857/891 and IC7300 are offered, catering to specific equipment needs. Beyond antennas, the store supplies practical accessories like transport bags, 12V power cables for transceivers, and even branded merchandise like the Antena Kit mug. Rodrigo Gonçalves, PP5BT, manages the operation from Blumenau, SC, Brazil, providing direct contact via WhatsApp at +55 47 9.9985.0155.

High Speed Multimedia (HSMM) radio, as introduced by John Champa, K8OCL, represents a significant advancement in amateur radio's digital capabilities, moving beyond traditional keyboard modes like packet radio. This initiative, driven by ARRL's Technology Task Force, focuses on developing high-speed digital radio networks capable of up to 20 megabits per second. HSMM primarily facilitates digital voice (DV) and digital video (ADV), enabling real-time video transmission from emergency scenes to an EOC without expensive ATV gear, often requiring only a laptop, a PCMCIA card, a digital camera, and a small antenna. The working group's initial efforts concentrate on cultivating microwave skills within the amateur community to build and support portable and fixed high-speed radio-based local networking, or **RLANs**. These networks prove invaluable for RACES and ARES organizations, as well as homeland security and other emergency communications. Field Day exercises and simulated emergency tests (SETs) are encouraged to hone skills in rapid site surveys and deploying broadband HSMM microwave radio networks, with examples like linking Field Day logging stations or antenna test results at the Midwest VHF-UHF Society Picnic 2003. Getting started with HSMM often involves adapting off-the-shelf **IEEE 802.11** (WiFi) equipment to comply with amateur radio regulations, typically operating in the 2.4 GHz ISM bands. While consumer WiFi gear has range limitations under Part 15 rules, proper setup under amateur regulations can extend coverage significantly, with test networks like the Hinternet achieving 5-15 mile ranges at 54 M bit/s using small mast-mounted dish antennas. Careful selection of equipment with external antenna ports, high transmit power, and low receive sensitivity is crucial, along with using low-loss coaxial cable like LMR-400 for optimal performance at these frequencies.

What happens in impedance space when the various popular matching networks (antenna tuners) are adjusted

This Field Day Vertical Antenna project is the result of many years of attending various field day sites and realizing that what was needed is a simple, easy to assemble vertical antenna. The design of this Field Day Antenna is not very novel and leverages ideas from Butternut verticals and ARRL publications. The one essential requirement was that the antenna can be raised by just one person. The design of this Field Day Antenna is an above ground mounted ground plane vertical.

Discover the key facts about what radio propagation is, the different types available and how they affect different frequencies.

What is antenna polarization, and why does it matter. Horizontal versus Vertical versus Circular polarization. Undestanding how antennas perform better with different polarizations.

Antenna most often used by Hams around the world. Inexpensive, effective and easy to build, what more could anyone ask for in a home made antenna.

There are quite a few recipes for building a suitable transformer for an end fed half wave antenna (EFHW), but I was never sure I really understood the main principles. So, I wound a bunch of transformers, made measurements on them using my NanoVNA, learned how to get what I really wanted out of the VNA measurements, and in the process discovered how to build better transformers and be able to predict what they will do

What do amateur radio operators worldwide, think of their passion? What do we wish for? What are we frustrated about? How many of us are active, versus those that are taking a break? Do we have favorite radios, antennas, or even favorite cw paddles? Do we prefer one contest over another? The best way to find out is if we all participate in Ham Census. Join in and let all amateur radio operators know your thoughts "share your views" then you can find out what everyone else is thinking, in real time. Help shape the future of ham radio by participating in the world's most complete survey of amateur radio.

Method, Units of Measure, and the Dipole Standard of Reference. This article helps in understanding where does beam gain come from in directional aerials like in example Yagi antennas.

Antenna patterns are all about interference. Presentation on wire antennas for HF bands. Dipoles, horizontal and vertical dipoles, effects of ground on radiation patterns, multi-band wires antennas. Knowing what you should expect from the radiation patterns for waves on your wires will help you choose what will work best for your needs. The principles of interference can lend insight into what to expect from a wire antenna.