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Theory, Modeling, and Practical Applications By W5JCK, presentation in PDF File. This presentation focuses on Near-Vertical Incidence Skywave (NVIS) antennas, which are crucial for short-range radio communications, particularly in military and emergency contexts. It explores NVIS theory, antenna models, and installation criteria while debunking common myths about reflectors. Key topics include usable frequency bands, optimal installation heights, and the impact of soil quality on performance. The presentation outlines the best bands for daytime and nighttime use, emphasizing the importance of understanding propagation characteristics to enhance communication effectiveness within 200 to 300 miles.

Browning Laboratories, Inc. has been a key player in the CB radio community since 1999, focusing on providing accurate information about Browning radio equipment. The website serves as a hub for enthusiasts, offering a wealth of resources including company history, myths and facts, and a collector's guide. It is supported by contributions from Browning enthusiasts and extensive research, ensuring that users have access to the most complete history available. In addition to historical content, the site features links to forums and other resources, fostering a community of CB radio operators and collectors. Whether you're a seasoned DXer or a newcomer to the world of CB radios, Browning Laboratories aims to bring people together through shared knowledge and passion for radio communication. The site is designed for optimal viewing and is regularly updated to maintain its relevance in the ever-evolving landscape of amateur radio.

Will we ever be able to dispel the myths? Steve Katz, WB2WIK/6

In the long history of beam aerials there has persistently existed the claim that certain types of aerials perform better than yagis.

Myths and basic truths on transmission lines

CO2KK exposes some myths about using 75-ohm feedline with 50-ohm rigs and show how to build a cotanget transformer

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.

Ladder Line Myths, Line Types, Spacing and Impedance, Length by KV5R

This resource examines the appropriate use of /M (mobile) and /P (portable) suffixes in amateur radio callsigns, specifically within the context of the UK Amateur Radio Licence. It addresses common ambiguities and challenges in determining operational status, such as operating from a summit or while walking. The discussion references the licence version in force before February 21, 2024, noting that while current regulations recommend but do not specify suffix use, the prior definitions remain relevant for understanding common practice. The content dissects key sections of the licence, including "Notes to the licence" (d)(i-iii) which outlines /A, /P, and /M usage based on location, and "Temporary Location" (jj) which defines /P operations. It also clarifies "Mobile" (17(1)(x)) as operating in or on a vehicle, on a pedestrian, or on a vessel on inland waters. The author provides examples and recommendations for choosing between /M and /P when both might apply, such as when operating from a parked car with a deployed mast or using a handheld on a summit. Historical notes from M1MAJ, G8ADD, and G6MZX are included, tracing the evolution of suffix rules from pre-BR68 days to the 1977 licence version. These historical perspectives highlight how past regulations have influenced current interpretations and persistent myths regarding /M usage. The resource emphasizes making an informed choice based on the licence and communicating the station's operational circumstances clearly.

Antennas, Transmission Lines, Tuners - Myths, Mysteries and Qualifiers By Don Wilhelm W3FPR

It is best not to know very much, than to know a lot of things which aren not true.

Myths and information about ladder line by KV5R

This page delves into the Inverted V antenna, a source of myths among ham radio operators. The author explores the behavior of this antenna type with a focus on a 20m half-wave dipole positioned 10m above the ground. From Pythagoras to high school math, the article simplifies the calculation of dimensions and angles for setting up an Inverted V antenna. It includes a spreadsheet for calculating hypotenuse length and angles, crucial for antenna setup. Additionally, it provides insight into the radiation pattern of a 'flat' half-wave dipole at 10m height. Useful for hams planning to optimize their antenna setup. In Norwegian.

Ham radio enthusiasts must prioritize lightning protection for their stations and homes to mitigate the risks associated with lightning strikes. Effective lightning protection involves dispelling myths, understanding the actual risks, and implementing proper grounding and surge protection. Key strategies include grounding all connections, protecting cables entering the station, and using surge protectors for power lines and control cables. Good grounding is essential for effective lightning protection.