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Operating a ZS6BKW antenna often involves understanding its lineage from the _G5RV_ design, with specific modifications by ZS6BKW to optimize performance on several bands. Through computational analysis and field measurements, the antenna's dimensions were refined to allow operation on 10, 12, 17, 20, and 40 meters without an antenna tuner. For 80, 30, and 15 meters, a tuner is necessary, though efficiency on 30 and 15 meters is noted as not particularly high. The physical configuration consists of two 13.755-meter radiating elements fed by a 12.20-meter section of 450-ohm ladder line. Tuning the antenna on the 20-meter band is critical, and any deviation in the ladder line's characteristic impedance necessitates recalculating the element lengths. The design is also referenced in the 12th edition of _Rothammel's Antennenbuch_, page 219. Proper common mode current suppression is crucial at the transition from ladder line to coaxial cable. This can be achieved with a common mode choke, such as several turns of coax wound into a coil or over a ferrite toroid like an Amidon T130. While a 1:1 balun is an option, it may introduce issues.

HD Communications Corp specializes in **RF and microwave amplifiers** engineered for demanding communication, defense, and industrial applications. Their product line includes precision-built, high-power solutions, along with RF connectors, filters, HF cables, and various accessories. The company also supplies tower hardware, valves, and tubes, catering to a broad spectrum of radio frequency infrastructure needs. Beyond amplifiers, HD Communications offers a range of **RF filters**, including low-pass filters, antenna filters, and solutions for RFI/TVI mitigation. Their inventory encompasses essential components like coaxial cable and various connector types, supporting both amateur radio and professional installations. The company operates as a manufacturer and vendor, providing direct sales of its specialized RF products.

Visually-oriented satellite tracking for commercial and military applications

Demonstrates practical solutions for reducing **Radio Frequency Interference (RFI)** in amateur radio operating environments, specifically addressing issues with PC monitors, receivers, and transceivers. The resource compiles advice from experienced operators regarding the selection and application of ferrite cores, including split cores and toroidal cores. It details specific material types like **43, 73, 75, and 77 ferrite**, outlining their effective frequency ranges for RFI suppression, such as 43 material for 30-400 MHz and 77 material for 2-30 MHz. The content provides part numbers for various ferrite products from manufacturers like Fair-Rite Products Corp, distributed by Amidon, and discusses their impedance characteristics across different HF bands. It compares the performance of various ferrite materials at frequencies like 4 MHz, noting that 75 material offers 27 ohms, 73 material 17 ohms, and 43 material just under 10 ohms. Additionally, it touches upon the use of bypass capacitors in conjunction with ferrites to create low-pass filters, emphasizing the importance of identifying common-mode versus differential-mode RFI paths for effective mitigation.

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

Plans and drawings of common amateur radio antennas, like jpoles, copper cactus, super jpole, omnidirectionals and quads

JIM, N0UQZ TS-2000 review

Dealer for Icom America (LMR/Marine/Amateur accessories) and Expert Electronics (SunSDR MB1) US dealer.

A 11 pages pdf file about monoband or multiband end fed half wave vertical antenna that is great for DX and very cheap to build by Steve G0KYA

Collection of Yaesu FT-100 comments

Bill Rinker, W6OAV, handcrafted this compact magnetic HF loop from copper and pvc plumbing supplies, a 12 volt motor, and some teflon sheets. He's had great reports with it.

What to have before you go.

Free programming software for the Wouxun KG-UVD1P, KG-UV2D, and similar radios.

Official website of the ICF group

How to check for propoer connector installation by using a common multimeter to verify conductivity and resistance.

Information and digital audio samples of various modem modulation types

Meimaris Communication Equipment based in Greece

Details Guglielmo Marconi's foundational contributions to radio communication, highlighting his 1898 Patent **7777** which introduced tuning circuits for independent simultaneous communications. Chronicles the historic transatlantic reception of the Morse code letter 'S' on December 12, 1901, from Poldhu, Cornwall, to St. John's, Newfoundland, a distance of over _3,500 kilometers_. The exhibit showcases early Marconi 10-inch spark transmitters, identical to those used on the _Titanic_, alongside Canadian Marconi crystal detector models. It also features high-end commercial receivers like the IP501, weighing **87 pounds** and originally priced at $595.00, demonstrating the robust construction and technological advancements of the era.

AP Communications CB and Amatuer Electronics Sales

Garmin Kenwood Icom Vertex Alinco and more

Canadiam ham radio dealer for Alinco, Alpha Delta,Bencher, Ameritron,Anli,Butternut,Comet,Daiwa,Cusfcraft,Icom,Kantronics,Laha,Vectronics,MFJ,Yaesu products

Issue 35, October 1992 Six News

Ham Radio Store in Austria, dealer for Flex Radio, Alinco, LDG, MFJ, Wouxun and many more ham radio brands

Establishing a robust, interconnected communication infrastructure across challenging terrain, the Island Trunk System (ITS) provides a network of open amateur radio repeaters for general and emergency communications throughout Vancouver Island, surrounding waters, and parts of the lower mainland on the West Coast of British Columbia, Canada. This system, largely off-grid, relies on solar power and batteries, necessitating careful operation, especially during night hours and low solar charging seasons, to preserve its energy resources. Maintaining the ITS involves significant effort from many hams, who appreciate adherence to regulations, including proper station identification. The system hosts a weekly social net every Monday evening at 8 PM, welcoming all participants, and also supports a Vancouver Island Region Emergency Radio Net each Wednesday at 19:15. Experimental projects like the Newcastle Ridge webcams, linked via 5.8 GHz broadband backhaul over 206 km to Nanaimo and Comox, demonstrate the innovative spirit within the ITS community. A new VHF repeater, operating on 146.880 MHz with a 141.3 Hz PL tone, was installed in Tofino, expanding system coverage.

Operating an amateur radio station often involves community engagement, and the Anne Arundel Amateur Radio Club (AARC) exemplifies this with a focus on public service and emergency communications. The club maintains repeaters, provides an Elmer program for new hams, and conducts training and testing sessions, fostering skill development across various age groups and experience levels. Members participate in activities ranging from contesting to kit building, promoting technical proficiency and camaraderie within the local ham radio community. The AARC hosts regular meetings on the first and third Thursday evenings, creating opportunities for fellowship and knowledge exchange. Their commitment extends to programs designed for kids, YLs, OMs, and both new and experienced operators, ensuring a broad appeal. This club's structure supports continuous learning and practical application of amateur radio principles, aligning with the core values of the hobby. Their emphasis on emergency preparedness highlights a critical aspect of amateur radio's public service mission.

Icom Kenwood Yaesu MyDel dealer, offer a wide range of ham radio products, transceivers, antennas, rotators, microphonrs, aerials, dummy loads, rf amplifiers and scanners based in UK

Industrial Communication Engineers (ICE) was a manufacturer specializing in **RF components** and solutions for amateur radio and commercial applications. Their product line included a range of RF parts, various types of filters, and RF switching products designed to enhance station performance and mitigate interference. These components were critical for hams engaged in contesting, DXing, or general operating, providing means to improve signal integrity and manage complex antenna systems. The company's offerings addressed common operational challenges such as RFI and TVI, with products like **low pass filters** and antenna filters. While the specific technical specifications of their product range are no longer available, such components typically provided significant attenuation of unwanted harmonics and out-of-band emissions, crucial for maintaining a clean signal and preventing interference with other electronic devices. The current status indicates the domain is for sale, suggesting the manufacturing operations have ceased.

Deploying robust antenna infrastructure for both fixed and portable operations often requires specialized support structures capable of withstanding environmental stresses while providing optimal radiating element placement. SMC offers a range of solutions, including pneumatic masts and push-up masts, designed to facilitate rapid deployment and reliable long-term support for various antenna types. Their product line encompasses antenna mounts, poles, and complete antenna systems, addressing the critical need for stable and efficient RF communication. The company's offerings extend to HF antennas, including dipoles and _NVIS_ (Near Vertical Incidence Skywave) antennas, which are crucial for short-range regional communications on bands like 80m and 40m. These systems are engineered for durability and performance, ensuring signal integrity across diverse operating conditions. With over **65 years** of experience, SMC has established itself as a global manufacturer in this niche. Their product portfolio also includes antenna support towers, catering to more permanent installations requiring significant height and load capacity for multiple arrays.

RadioComm can be used to program your Icom radio's memory, or to create nice radio-frequency spectra or to interface your radio to a huge database of frequencies.

Intended for portable long-term usage and also good for Field Day Events article by By Steve KB1DIG & Kim KB1GTR

Deutschen Amateur Radio Club Awards

Otto engineering is comprised of two divisions otto controls and otto communications. otto controls designs and manufactures a full line of switches and grips used in heavy equipment, aerospace, marine, medical and other demanding applications. otto communications designs and manufactures audio accessories for two-way radios used in public safety, police, fire, retail, hospitality manufacturing and other markets.

Los Angeles County Disaster Communications Service a public service organization using Amateur Radio

Showcasing a specialized product line, Advanced Receiver Research presents a comprehensive catalog of **low noise preamplifiers** and microwave **Gunnplexers**. The offerings span a broad spectrum of radio frequencies, from VLF, LF, MF, and HF bands up through VHF, UHF, and microwave, catering to diverse applications including amateur radio, commercial installations, and military systems. Their product range includes mast-mount preamplifiers, inline attenuators, power dividers, and various coaxial components. My own experience with similar low-noise front ends for weak-signal work on 2 meters and 70 centimeters underscores the critical role such components play in maximizing receiver sensitivity, especially when chasing distant DX or engaging in EME. The detailed product descriptions and technical specifications provided on the site allow operators to select the optimal preamplifier for their specific band and noise figure requirements, essential for improving signal-to-noise ratio. The site also lists specialized products for unique applications like Nuclear Magnetic Resonance (NMR) and Studio Transmitter Links (STL), demonstrating a depth of engineering capability beyond typical amateur radio fare. This breadth of offerings, coupled with clear ordering and warranty information, positions Advanced Receiver Research as a key supplier for high-performance RF components.

This article compares two commercial vertical antennas for the 4-meter amateur radio band: the Watson WVB-70 half-wave and the Sirio CX4-71. The Watson measures 2.03m in length, costs around £40, and exhibited adequate performance but required additional waterproofing after rain affected its VSWR readings. The longer Sirio CX4-71 (3.02m) performed noticeably better, delivering signals approximately 2 S-points stronger than the Watson. The Sirio demonstrated high build quality, a stable 1.2-1.4:1 VSWR, and weather resilience, though minor VSWR fluctuations were observed during rain and frost. Both antennas are half-wave designs requiring no ground plane radials.

This resource details the four primary functions of a ground system: lightning energy dispersion, equipment safety, RF return path provision for end-fed antennas, and management of induced RF currents. It clarifies that a ground system's effectiveness varies depending on its specific function, noting that a good lightning ground might not be an effective RF ground. The content emphasizes that proper antenna system design, including baluns and appropriate feedline lengths, often negates the need for an RF station ground to mitigate common mode currents or RFI in the shack. The article quantifies lightning energy, stating its peak is in the dozens or hundreds of kilohertz, with damaging energy extending to hundreds of megahertz, and currents reaching thousands of amperes. It recommends solid, wide, smooth copper surfaces for ground leads to achieve low impedance across a wide frequency range. The author, W8JI, shares practical insights from his station, which includes two 300-ft towers and four 130-ft wire verticals, detailing his use of common point grounds and _DX Engineering RR-8 HD_ antenna switches for lightning protection without coaxial surge protectors. Specific examples of antenna systems prone to common mode current problems are listed, such as random wire antennas without proper feedline lengths and off-center fed dipoles. The text also explains how a ground screen or radial system can reduce local noise sensitivity for vertically polarized antennas by covering the lossy earth.

Explore this high-resolution ITU Zones Map, a critical reference resource for amateur radio operators, international broadcasters, and telecommunications engineers. Originally established by the International Telecommunication Union – Radiocommunication Sector (ITU-R) Broadcasting Services Division (1999), this chart accurately divides the globe into 90 specific CIRAF zones. This authoritative visual guide is indispensable for planning High Frequency (HF) radio propagation, scheduling international broadcasts, and verifying locations for radio contests and awards. Distinct from the 40 CQ Zones, the ITU zoning system provides the official administrative framework used for global frequency management. This digitally enhanced version ensures maximum clarity of zone boundaries and numbering (e.g., Zone 28 for Central Europe), making it an essential tool for technical accuracy in logbooks and station management. It serves as a trustworthy standard for educators, hobbyists, and industry professionals alike.

CommCat Mobile is a free integrated spot management, remote radio control, and logging app for the iPhone. CommCat is required for remote control.

The document titled 'Extending the Range of Your Handheld' by WG7S is a guide on how to extend the range of your handheld VHF UHF transceiver by using an external antenna. It provides information on comparing popular models, selecting the right antenna, and resources for amateur radio antennas.

Speakers for Amateur Radio, 2-Way Radio, Shortwave and Scanner listening

Dds data- communication Data and Tele-Communication Solutions: UMTS GSM GPRS Telemetry programmers Adeunis RF systems, antennas, radio transmission modules, oscilloscopes GPS and coax cables dealer in Holland

Specialist in the design and supply of Radio Communications Equipment and Systems. West Sussex England. Antennas, traps and baluns inline isolators, Outbacker Antennas, Mobile Mounts and Accessories

Community blog at livrjournal

Largest Capacity of 200,000 MT for Towers & market leader in India with backward integrated rolling & manufacturers of Shelters, V/UHF, Patch Panel Antennas, DIAS & DWDM Equipment

This page presents a curated list of individuals who have made significant contributions across various fields while also being active amateur radio operators. For instance, Dr. Joseph H. Taylor, co-winner of the 1993 Nobel Prize in Physics for the discovery of binary pulsars, is recognized for developing the _WSPR_ and _WSJT_ weak signal mode software. Similarly, Wilson Greatbatch, inventor of the cardiac pacemaker with over **150 patents**, is featured. The resource details the diverse backgrounds of these hams, from Professor Donald H. Menzel, an astrophysicist at Harvard, to Hiram Percy Maxim, often called "The Father of Amateur Radio," who also pioneered in the automobile and aviation industries. King Hussein of Jordan, JY1, is noted for his active participation on 20 meters, engaging with fellow amateurs like Pat Kilroy, WD8LAQ. Other entries include Arthur M. Young, designer of Bell Helicopter's first model, and Marlon Brando, KE6PZH/FO5GJ, known for operating from his private island in French Polynesia. Peggy Sue Gerron-Rackham, K5PSG, gained her license after a special event station, demonstrating the hobby's broad appeal.

The MEL PICBASIC Forum serves as a community hub for users of Micro Engineering Labs PICBASIC compilers, facilitating discussions related to PIC microcontroller programming. It features dedicated sections for various compiler versions, including mel PIC BASIC, mel PIC BASIC Pro, and PBP3, each containing numerous threads and posts detailing specific programming challenges and solutions. The forum also provides areas for frequently asked questions, general PIC BASIC discussions, and commercial assistance requests. Specific sub-forums address advanced topics such as PBP Extensions, Code Examples, and AI and PICBASIC, offering insights into extending compiler functionality and integrating artificial intelligence concepts. Furthermore, the platform includes sections for Data Communications, covering USB, I2C, 1-Wire, GSM, and serial communications, which are critical for interfacing PIC microcontrollers with external devices. A dedicated area for PIC Programmers allows for discussions on programming hardware and techniques. The forum's utility is enhanced by its extensive archives of user-contributed solutions and examples, which can assist hams in developing microcontroller-based projects for radio applications. The platform's structure supports knowledge exchange among hobbyists and professionals working with PIC microcontrollers.

Kenwood TH-D7(G) and TH-D7A commands reference

This resource, originally intended to detail the technical specifications of the **Clover** digital communications mode, currently presents a "Page not found" error. The _Clover_ mode was designed for conveying 8-bit digital data over narrow-band high-frequency radio channels, offering robust performance under challenging propagation conditions. Its design focused on efficient data transfer and error correction, making it suitable for amateur radio operators seeking reliable digital links. The absence of the page prevents analysis of specific technical parameters, such as modulation schemes, data rates, or error correction codes that would have been presented. Historically, Clover offered significant advantages in throughput and reliability compared to earlier digital modes over HF, often achieving higher effective data rates than modes like PACTOR or AMTOR under similar signal-to-noise ratios. Without the content, a direct comparison of its performance metrics or practical application scenarios is not possible.

This page is about the RSGB's Propagation Studies Committee, its work, services and current projects, together with guides to where to find more about matters relating to propagation on the Internet at all levels from introductory to professional. Watch this space!

Wheaton Community Radio Amateurs (WCRA - W9CCu), Wheaton, Illinois