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Selecting an appropriate antenna system for shortwave broadcasting involves evaluating various types based on performance, cost, and operational parameters. This resource details the critical specifications for broadcast antennas, including average and peak power ratings, directivity, takeoff angle (TOA), horizontal beamwidth, and gain, emphasizing that a 100-kW transmitter requires an antenna rated for 150 kW average and 400 kW peak. It clarifies that low TOA signals travel thousands of kilometers, while high TOA is for local coverage, and nearly all modern shortwave broadcast antennas are horizontally polarized. The article explores specific antenna types, such as Log-Periodic Antennas (LPAs), which offer wide frequency ranges (e.g., 2-30 MHz) and directional patterns with 11 dBi gain, costing from $20K to over $100K for multi-curtain versions. Dipole arrays, also known as curtain antennas, are prevalent in international broadcasting, featuring steerable beams (±15° and ±30°) and mode-switching capabilities to alter TOA, with high/low pairs costing over $1 million. Fan dipoles are noted for omnidirectional patterns, smaller size, and lower cost for low-power applications, while rhombics, though simple, require resistive termination and incur several dB of I2R losses. Balun considerations are crucial, as most communications baluns are not rated for the higher average and peak powers of AM broadcast transmitters. Modern shortwave antennas utilize durable materials like Alumoweld wire rope for radiators and support elements, avoiding copper, fiberglass, or materials prone to stretching or deterioration. Feeder systems for high-power stations often require tapered-line baluns to convert 50-ohm unbalanced power to 300-ohm balanced for connection to the antenna.

This type of antenna has same performance as a dipole, but requires only one single mounting point

A low cost, low profile DX antenna fro 17 Meters

FT2 is an innovative digital mode for amateur radio, developed by IU8LMC with support from ARI Caserta. It utilizes the same codec as FT8 and FT4 but compresses the transmission cycle to just 3.8 seconds, allowing for a complete QSO in as little as 11 seconds. This remarkable speed enables operators to achieve approximately 240 QSOs per hour, making it particularly advantageous for contests and DXpeditions. The FT2 protocol has been rigorously tested on-air, with successful QSOs verified down to -12 dB SNR on both 40m and 80m bands. The mode's efficiency and speed are a significant advancement in digital communications, providing a new tool for amateur radio operators looking to maximize their contact rates. As an experimental release, the software is subject to updates, ensuring continuous improvement and adaptation to user feedback.

German Ham radio dealer for hf radios by Icom Yaesu Kenwood Alinco and Alan

Harv's Hamshack Hack. A remaster of the KNOPPIX distro for Amateur Radio Operators (Hams) who have no prior experience with Linux. Provides a complete OS, software for hobby, web, and word tasks. All contained in an .iso file ready to burn to CD.

Macintosh audio spectrum analyzer that allows the user to view live audio in a standard frequency plot, a stereo oscilloscope view and a waterfall display

This easy to build antenna works well for satellite or terrestrial communication, horizontal or vertically polarized by Anthony Monteiro, AA2TX QST Article

Ham Radio Audio Stream: listen live to German amateur radio repeaters.

Aviation Radio Service by FCC

Bellingham Antique Radio Museum, private collection gathered over the past 25 years by Jonathan Winter.

Maintenance and repair of a Cushcraft R5 vertical antenna

Build your own cobweb antenna followning M0MRR instructions and notes

The total length of this antenna is 41m, height is about 11m, and diameter of element is 2mm. JA7KPI modified this antenna originally used as Inverted-V type of 80m band Dipole. Works on 40 - 80 meters band with acceptable swr.

K6SGH hamloop antenna for 15 meters band

A description page on how build delta loops antennas. In italian

A large jpeg DX World map that include ITU Zones, grid squares and prefixes. This high-resolution DX World Map is an essential tool for amateur radio operators. It clearly displays ITU zones, CQ zones, grid squares (Maidenhead Locator), and DXCC prefixes, helping you to plan QSOs, track propagation paths, and participate in global contests. Whether you are a seasoned DXer or a beginner, this map provides a clear, detailed view of the radio world, improving your station's efficiency and geographic awareness. Available in JPEG format, it's perfect for display

Construction tips to build an automatic``satellite tracking rotor controller using``PIC16F877 IC.

A 3 element DELTA LOOP on 20 meter, 4 on 15 and 5 on 10: my new beam (Just some good ideas)

Bandplans for region 1 in pdf format by DARC

This web player allow to listen to the Anne Arundel County Police and Fire Live Scanner Radio Feed

FT857 and FT897 Interface PCB and schematic

GP for ms dos and ms Win by DD3DJ

Paddles, Keys, Filters, Antennas

A freeware program to dig out weak signals buried in noise, functionally similar to the excellent FFTDSP of AF9Y, but with the added bonus of real time audio filtering of the incoming signals. Just point and click with the mouse, and the selected signal will stand out from the QRM and noise.

ARRL WAS Map, Map of USA call districts by ARRL and edited by AA70A

How to DIY a 9:1 balun in french

Windows 95/98 based program to decode PSK31 mode by AE4JY, freeware

This page describes a homebrew 80/40 meter trap vertical antenna. Includes an interesting antenna raising system that allow easy setup and tuning.

A 13,8v/5Amp 78H05 based power supply for portable use. In this example used to power up a Yaesu FT-817

This is a site for Kingsport,Tenn police and 911 a good site to check out. You must register at live365 but it is worth it.

based on the famous Curtis family of morse keyer chips and has a proven record of dependability.

This transverter was built in 1994, a discription in three parts (german language) for DOWNLOAD as PDF-files. Circuit, printed-boards and layouts in the files

Suitable antenna for owners of an IC706 or FT817, 857 and other HF portable transceivers. You can an be QRV in a few minutes on all ham-bands from 80m to 6m and even on 2m by PA0FBK

A full wave 2-meter VHF omnidirectional antenna by ON6MU

The Inverted L antenna is a versatile and efficient design suitable for small gardens, allowing amateur radio operators to operate on multiple bands. This project outlines the construction of a 5-band inverted L antenna, which can cover HF bands effectively. The design is particularly advantageous for those with limited space, as it requires minimal ground space while providing good performance. The antenna can be easily constructed using common materials, making it accessible for both beginners and experienced hams. In this guide, GM0ONX shares detailed instructions on how to build the inverted L antenna, including dimensions and tuning tips. The project emphasizes the importance of proper installation and grounding to ensure optimal performance. Additionally, it discusses the antenna's compatibility with various transceivers and the potential for portable operation. This resource is ideal for hams looking to enhance their station with a multiband antenna that performs well in limited space.

Cobra Electronics is known the world over as a manufacturer of superior quality communications and electronic equipment

Reducing noise to your antenna can gain your aerial performance, learn how.

Explanation of antenna basics concepts like antenna gain at marc's technical pages

A 6 m 50MHz J-Pole antenna by VKADC

Manufacture CATS antenna rotator and digital controls. Service, stock, and provide parts for top quality AMERICAN-MADE antenna rotators from companies such as Alliance, C.A.T.S., CDE/Hy-Gain, and Channel Master, both young and old.

Info on this discontinued HF Transceiver

D-RATS is a small application designed to provide data communication capabilities with D-STAR radios. It supports text chatting, file transfers, position reporting and mapping, and much more! It is written in Python using GTK to run on multiple platforms.

EhoCw is a freeware morse keyer software and a morse code generator and even a morse code decoder. It runs on your PC under windows (from NT to Vista, windows 7). This software can be used efficiently by any telegraphist, confirmed or beginner who wants to use his personnal computer as a memory keyer, you can use it to learn morse code and you can use it to decode morse code

The Coax trap program computes design parameters for the construction of coaxial traps for HF usage. Typically these are constructed from PVC tube and RG58/59 coax

Automatic SWR meter and semi-automatic tuning unit by F1FRV

MM Antenna Analyzer by JE3HHT Makoto Mori based on the moment method, which was introduced in MININEC. Download MMANA Free from this page that offer download of basic version and link to the MMANA pro version.

Some thoughts on a "hardware-store special" 2-meter quad, and a modified quad for 2 or 10 meters by K3MT

Contest Log Converter it's a Windows program that allow to convert data file between the most used Contest Log. The program allow you to convert 12 different type of contest, selected from the common contest managed from the Contest Log program. The follow program ,CT by K1EA, TR by N6TR and NA by K8CC are full supported with the conversion of the most famous world contests.

Shakespeare Composites & Electronics Division manufactures a complete line of unmatched CB, CB marine, and military antennas for a veriety of applications.