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Exploring these mysterious transmissions and how their strong following has created a niche in the community. Free article in PDF Format from QST November 2019

A considerably shortened Magnetic Loop antenna with performance of a single conductor text book magnetic loop.

How manage and quantify ground loss in vertically-polarized antennas by VE3VN

A helically wound vertical antenna experiment. 14 meter of wire wounded on a 8 meter fishing pole with 4 elevated radials

A simple, cheap and easy to build 26 feet long vertical antenna that works DX on 20 - 10 meters including WARC Bands, it is designed for portability for field days, camping, or permanent installation, cost, and to achieve at least 1/2 wavelength on the WARC bands.

This circuit is very simple and has a fantastic range of potential uses.

Design for a quarter wave vertical antenna, for the top band in use at V31YN

A two way morse code practice set by VK3YE

Article about an end-fed anntenna for the 17 and 12 WARC Bands. 30 meters is not included in this project. This antenna includes a 14 windings unun impedance transformer using a FT-140-43 ferrite toroid, that should be enought for a 100W PEP.

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

A 102-inch vertical whip, commonly a CB antenna, forms the core of this low-profile 10-meter antenna design, optimized for the 28 MHz band. The construction details specify three 8-foot radials made from scrap wire, connected to a common point. This simple yet effective setup is designed for ease of construction and deployment, making it accessible for operators with limited space or materials. The design emphasizes using readily available components, including PVC pipe for the mast and a SO-239 connector for the feedline, ensuring a straightforward build process for a resonant quarter-wave vertical. Field results indicate that this antenna provides good performance for local and DX contacts on 10 meters, despite its compact footprint. The author, N8WRL, shares practical insights into its construction and tuning, highlighting its suitability for temporary or permanent installations where a full-sized antenna might be impractical. Comparisons to more complex designs suggest that this low-profile vertical offers a respectable signal-to-noise ratio and effective radiated power for its size, proving that simple designs can yield satisfying on-air results.

If you want to design vertical antennas you can find all theory and formulas used to model a vertical aerial calculating capacitance, reactance, building the inductor and calculating resistances. Includes an excel spreadsheet to calculate efficiency.

The course is for those not knowing a dit from a dah, first introducing the individual to learn code by sound and progresses in 12 lessons to 5 words per minute. Each lesson is about 30 minutes and recommendation is to listen to each twice before moving on to the next one.

A page describing how to home made a custom 9:1 balun for a common portable wire antenna. The author suggest to use 4C65 or FT140-61 toroids instead of the common Amidon T200-2

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

A Programming-Free Automatic Arduino Antenna Switch project published on NCJ

The intent of this article is to help the semi-non-technical person understand what is inside the Drake TR-7(A) Transceiver, how it works, and discusses simple adjustment and modifications the end-user can perform

Hand made RF sweeper made to adjust the pass band of crystal filter

Presentation about Practical Antenna Modeling Using the NEC Codes with examples of HF wire antennas and 4NEC2. How to define and edit the models, Running the simulations, Work some examples, Variables usage, Deal with Feed Lines and ground

Plastic tubing and custom plastic tubing from a manufacturer that specializes in the custom manufacturing of close tolerance plastic tubing products.

This page is a short description of the four phased verticals system for 160m 80m and 40m

Mobile RFI, often manifesting as persistent noise in the receiver even with the antenna disconnected, frequently originates from the vehicle's power supply system. This guide details systematic troubleshooting steps, beginning with isolating the radio from the car's 12-volt supply to confirm the power system as the noise source. It emphasizes the critical importance of drawing power directly from the battery using **heavy gauge wire**, bypassing the fuse block to leverage the battery's natural capacitance for RFI suppression and ensuring a solid RF ground. Proper routing of power lines through the firewall is also covered, advocating for dedicated grommeted holes to prevent inductive coupling from other wiring harnesses. The article stresses the necessity of fusing both positive and negative leads from the battery, a crucial safety measure to prevent damage to the rig and mitigate high-current risks should the battery's engine block ground become compromised during service. Addressing **alternator whine**, a common high-pitched noise that varies with engine speed, the resource suggests checking battery connections and the alternator-to-battery harness for looseness or corrosion. It also mentions the utility of adding an external RF noise suppression capacitor in parallel with the alternator's internal capacitor for enhanced filtering, and the effectiveness of commercially available in-line power supply filters.

Homebrewing an W3HH Antenna in french

Eham article by Vince Waelti (K9TSU)

Funky Homepage: History, News, Playlist, etc.

A project for a vertical antenna for 60 to 20 meters by KV5R

Beacons on 4 meter band

The radiating part is the vertical half of the dipole. You get nearly radiation in all directions, the second half must not be in 180°. The table below show how we get an impedance for direct feeding of 50Ohm coax. by DK7ZB

An homemade antenna tuner project that should be small, easy to build and cheap. This automatic antenna tuner can work as locale or as remote. The tuner has EEPROM memory for store settings for faster tunning and four interfaces

How to receive automatically NOAA wather satellite images with a Raspberry Pi and a RTL SDR. This project requires a Raspberry Pi 3 Model B a common NooElec SDR Dongle and a QFH Antenna in the attic. Article explains how to setup and configure software but no instructions on antenna.

An article about the Rybakov 806 Vertical antenna. The classic Rybakov configuration is a 7.6m or 8m ( aprox 25 or 26 feet) wire fed through a 4:1 UNUN

Describes Atlantic Tower Services (ATS), a company specializing in antenna tower erection and maintenance, operating from Orlando, Florida. ATS offers a range of services including site maintenance, structural repairs, system modifications, and complete tower installations for various communication needs. The company emphasizes its capability to handle diverse tower projects, from routine inspections to complex upgrades, ensuring structural integrity and optimal performance for amateur radio and commercial installations. ATS focuses on delivering reliable infrastructure solutions, supporting the backbone of communication systems. Their service portfolio covers critical aspects of tower ownership, addressing both preventative care and reactive solutions for existing structures. They are equipped to manage projects involving different tower types and heights, adhering to safety standards and operational best practices. Services include **site maintenance** and _structural modifications_.

By Floyd Sense K8AC

This processor controlled autoranging sniffer has become popular for vehicle based foxhunting in Australia

TBNoticias dx newsletter in spanish

160 to 40 meters inverted L antennas projects

Transferring Radio Frequency Energy from Your Transmitter to Your Antenna by Don Keith N4KC

K1JJ presents a compilation of insights regarding vertical radial ground systems, specifically applied to 160m vertical arrays. The resource details 19 distinct observations and recommendations, emphasizing that ground radials primarily reduce ground losses rather than influencing pattern formation. It explains that RF current flows inefficiently through average soil, necessitating copper radials to create a low-resistance path back to the antenna base. The content suggests that **50-60 radials** are generally sufficient to achieve optimal efficiency, with diminishing returns beyond that number, and that radials should be laid on the surface for best performance. The discussion also addresses practical aspects such as wire gauge, installation techniques using 'U' shaped staples, and methods for connecting radials in multi-element arrays. It highlights the importance of radial length, stating that 1/4 wave radials are a crucial minimum, and that for 160m, radials should be at least _100 feet_ long. The resource critically examines the efficacy of elevated radials versus ground radials, noting that while a few elevated radials may suffice for VHF, HF applications, particularly on 160m, require extensive ground radial systems to efficiently collect RF currents in the near field. It also touches on the impact of radial systems on parasitic elements and the significance of symmetrical radial patterns for minimizing losses. Further practical advice includes wire type recommendations, proper soldering and weatherproofing techniques for radial connections, and considerations for integrating steel towers into the ground system. The author shares personal experience with installing 60 quarter-wave and half-wave radials under each of three in-line verticals, expressing satisfaction with the results.

Plans for building your own 3-element beam for use on 6m.

Generate and download morse code practice files in the mp3 format. You can even download the texts to check the resources. Files can be generated online by selecting speed, tone and duration.

A vertically-polarised VK2ABQ Antenna for six meter band

A Yagi-Mag antenna for the 4 meters band with NEC and MMANA files plans and pictures

Installing the Cumbria Designs X-Lock VFO Stabilizer, and Improving The TR7 Audio Quality

Introduction to NVIS antenna and NVIS propagation. A simple NVIS antenna can be constructed as shown in this article

The **Escort** series Tactical Carrying System provides robust protection and enhanced portability for popular HF transceivers, addressing the need for secure field operation and transport. These systems, designed for models such as the Yaesu FT-857D/891, FT-991, FT-817/818ND, and Icom IC-706/703/7000, IC-7300, feature military-grade construction with front panel protection and versatile carrying strap attachment points. Operators can confidently deploy their rigs in various environments, from SOTA activations to casual field days, knowing their equipment is safeguarded against bumps and impacts. Beyond tactical carriers, Portable Zero LLC also produces the **Sherpa Pack** for the Yaesu FT-817 and the Field Power 12 and Field Power 3 Battery Cases. These accessories complement portable operations by providing essential power solutions and additional carrying options, facilitating extended off-grid activity. Established no later than 2013, Portable Zero LLC manufactures its products in the USA, leveraging CAD design and CNC precision laser cutting for consistent quality. The company's commitment to enhancing portable amateur radio operations is evident in its specialized product line, available in finishes like Black Texture and OD Green.

Learnings from the 6Y4A CQ WW CW Contest By K2KW and N6BT

A hobby club for those dedicated to collecting, restoring, and preserving vintage radio and television equipment.

Little circuit of a Morse Code Oscillator is presented here. Excellent for learning and teaching Morse code

Some observations on the Yaesu FT-817 5W portable HF VHF UHF transceiver with some pictures and movies

The **HamRacer** voice keyer, a Windows-based application, is showcased in this video, illustrating its utility for radio amateurs participating in SSB contests. It functions as a synthesized PC-based voice keyer, specifically designed for HF and VHF SSB contest operations, allowing operators to transmit pre-recorded or text-to-speech generated messages during rapid-fire exchanges. The demonstration includes actual recorded QSO examples from a contest, featuring contacts with stations such as SP6OWA, S57O, OK1IEI, 9A1DL, OE1PAB, OK1GTH, and 9A1E. These examples highlight the software's practical application in a live contesting environment, demonstrating how it facilitates contest participation for operators who might otherwise face challenges with traditional voice keying. The resource provides a direct look at the software in action, emphasizing its role in promoting inclusivity within the amateur radio contesting community. It details the use of Windows SAPI for speech synthesis, a core component of HamRacer's functionality.