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This magnetic loop DIY site is ment to be an introduction into making DX high quality magnetic loop antennas that will beat any dipole

Mini-Operating Guide includes useful hints on Using the HM-133 Microphone, Basic Operation, Operating through a Repeater, Programming a Memory Channel and Assigning a Memory Channel to a Memory Bank

Presentation of the QO-100 the first geostationary OSCAR from Qatar by AMSAT-DL

A collection of 450 MHz Cheap Yagis that have proven great portable operations, back-packing and transmitter hunts, and are something inexpensive you can throw up in the attic for that weak repeater

Although most Preselectors are designed with an internal T/R relay, theoretically enabling direct insertion between the transceiver and the antenna, there is a problem when running CW, especially when running full QSK. The switching time of the internal relay is too slow to follow full QSK. The best way to avoid this problem altogether is to insert the Preselector directly into the transceiver’s RX antenna line, thus avoiding entirely the need to switch the Preselector in and out.

This free app encode pictures in Slow Scan TV SSTV signals. Support the most popular modes Martin 1, Martin 2, Scottie Modes, Robot and Wraase modes. Image editing is even possible with som text overlaying features

An inductance and capacitance meter, measuring range is from 0 to >0.1uF for capacitance and 0 to >10mH for inductance. A project by Phil Rice, VK3BHR

A homemade morse code decoder project, providing a detailed schematic and pictures

All available frequencies & offsets configurations for repeaters can be downloaded as database for Kenwood MCP-2A memory channel programming software for TM-D710 & TM-V71. Zip file is no more available from the author, but the full table of frequencies is still online

Have you ever thought of setting up a portable HF station for an activity like the Field Day ?

Operating on Airplane scattering. Scattering of radio signals by airplanes. An introduction to operating ariplane scattering, using aircraft to redirect RF that would otherwise be lost in space. Antenna Pointing, Doppler Shift/Digital Modes, using digital modes to operate airscatter.

An explanation of the different procedures and definitions that are commonly used for blocking dynamic range (BDR) measurements. Dynamic range in general is the ratio between the weakest signal a system can handle and the strongest signal the same system can handle simultaneously without an operator switching attenuators or turning volume potentiometers

The Icom IC-7300 is a popular SDR transceiver known for its excellent performance in ham bands. However, users have reported issues with reception reliability outside these bands due to ADC aliasing. This phenomenon occurs when the sampling rate of the radio interacts with frequencies outside the intended range, leading to unwanted signals being received. For instance, when tuned between 30 to 36 MHz, users may inadvertently pick up WFM broadcast signals or PMR communications due to aliasing effects. This guide outlines modifications to improve the IC-7300's performance by addressing the low-pass filter design, which is crucial for reducing interference from these unwanted signals. The proposed modifications involve adjusting the low-pass filter on the PA unit to better attenuate frequencies that cause aliasing. Measurements indicate that the original filter design allows significant signal leakage, leading to false receptions. By implementing the suggested changes, users can achieve a notable reduction in unwanted signals, enhancing the overall functionality of the IC-7300. While the modification requires careful soldering, the benefits in performance make it a worthwhile endeavor for serious operators looking to optimize their SDR experience.

Collection of several topics on antenna tuners and their performance. Why use an antenna tuner? How does an antenna tuner…tune Does an antenna tuner fool the radio? Will an antenna tuner waste power? Can an antenna tuner help get more power to the antenna?

This presentation applies to HF / VHF / UHF antennas and is about 14 different type of antennas suitable for indoor od apartament installations

This morse key and buzzer design only requires parts that one may already have or are easy to find on the web. There is nothing critical except that the contacts must meet when the key is depressed.

A document that will guide you on Coaxial-Cable trap optimization process to gain on global antenna performance and on increasing effective bandwidth.

This is a very small vertical 160m antenna that fits in the loft of even my small house. It was built as a way of getting a signal out on 160m for local AM contacts, but the local noise level was far too high to allow it to be used at night for this purpose. However, on WSPR it did a pretty good job with WSPR spots from a very long way across Europe being received when running 2.5W out.

A QST Article published in November 1922 is about the origin of Beverage antennas, an unidirectional antenna type that was discovered and experimented for the first time in that period. This article is the introduction to beverage antenna theory, by the homonimous autho H. H. Beverage.

Experimenting with capacitive antennas for 40 and 80 meters band. A very space-saving antenna with good receivings caracteristics

MorseKOB is a program for doing landline telegraphy and American Morse with the help of a computer. Can run on Mac OS and Linux, in addition to Windows.

This article describes a multi-band antenna design for amateur radio enthusiasts by G3FEW. The antenna is designed to cover at least five HF bands with low SWR and without the need for an ATU. It is also designed to be easy to construct and adaptable for different locations. The antenna is a full-wave dipole with traps at the quarter-wave points. The traps are used to tune the antenna to different bands. The antenna can be fed with a 4:1 balun. The article includes instructions for building the antenna, as well as information on the theory behind its operation. The author also discusses the results of his tests with the antenna. This multi-band antenna is a well-designed and versatile antenna that can be used by amateur radio enthusiasts on a variety of bands. It is relatively easy to construct and can be adapted for different locations.

Operaring portable during field day by VK4ADC

Surprisingly, although PCB soldering is the core process of electronics assembly, few people do know how to solder reliably

Unlock the secrets of RF signal optimization in a presentation covering Balun essentials, diverse types, SWR Analyzer checks, revealing results, Ferrite impedance measurements, and practical applications on feeders and house conductors.

Recent researches seem to support the hypothesis that Sporadic E propagation could be connected to presence of thunderstorms.

Around 17% of the U.S. population experiences some degree of Dyslexia, a condition affecting language processing that can hinder amateur radio license candidates, often leading to repeated exam failures despite diligent study. This resource outlines methods for Volunteer Examiners (VEs) and Elmers to identify and assist candidates with cognitive disorders like Dyslexia and **ADHD**, which affects approximately 4% of U.S. adults. It emphasizes recognizing patterns in missed answers, such as spatial placement errors on answer sheets, and suggests reading questions aloud as an accommodation. The author, NC4FB, shares a structured approach developed over three years, involving extensive candidate interviews and a self-study program. This program utilizes specialized software with keyword highlighting and a unique font to improve comprehension for Dyslexic/ADHD candidates. It also incorporates **MP3 audio files** for subelement questions and correct answers, providing an alternative study method for those who benefit from auditory learning. Key elements of the support strategy include repetition, positive reinforcement, and timely progress updates, often visualized with a color-coded table tracking scores of 85 or higher. The goal is for candidates to pass three consecutive sample exams with at least 85% before attempting the actual license exam, demonstrating mastery of the material.

Two easy to build microcontroller projects for machine recognition of hand-sent morse code

Starting March 23rd, the Peterborough Amateur Radio Club (PARC) conducts a virtual licensing class via Google Meet, led by Mark, VE3SB. This course comprises seven two-hour lessons, held on Mondays at 7 PM EST, focusing specifically on material required to pass the ISED exam. The registration fee of $60 covers the course, including in-person or remote exams, and grants participants a PARC membership for the remainder of the calendar year. Outside participants are welcome to join the virtual class, with exam options available upon completion. While recommended study material can be purchased separately, Peterborough-area participants have the option to arrange for a loaned copy of the book. The club emphasizes practical learning for exam success.

This HOWTO explains in detail how you can use the Kenwood TS-590S USB, COM and ACC2 ports for digital operation, set up the radio for digital data and digital voice operation

A small active voltage probe antenna to aid reception on the LF bands

From buying an amateur radio transceiver, choosing the correct power supply, selecting the antenna and its feed line, to choosing the best microphone and accessories. A nice presentation for beginners.

Modifying the Collins KWM-2 for Serious CW Operation, Make this old SSB workhorse perform like it should on CW.

Yaesu FT-710 AESS MF/HF and 6-Meter Transceiver review on QST

The Bazooka antenna, a coaxial dipole, functions as an omnidirectional antenna with vertical or horizontal polarization. Patented in 1939 and refined in 2006, it features a quarter-wavelength coaxial cable with separated conductors. The outer conductor connects to a sleeve, while the inner conductor extends vertically. Initially complex, it has been simplified for versatile use, including military applications. Adding elements can modify its behavior for NVIS or Yagi-Uda configurations. Experiments in 2007 at the Campus de Pesquisas Geofísicas in Paula Freitas-PR demonstrated consistent VHF and UHF performance, showing reliable return loss measurements despite variable weather.

Start by getting your audio levels sorted out, Having your levels correct is critical to maximum effectiveness in both TX quality and also for being able to decode signals properly. Guide to Filters and other Rig Settings to optimize your output signal

An analysis and performance improvement of the HyGain TH3JR on the 20 meters band.

Explore two magnetic loop antenna constructions, utilizing a 6-foot and a 12-foot square loop. Accompanied by a detailed description, the 6-foot loop features a built-in stepper motor control circuit, while the 12-foot loop incorporates a separate loop controller. Efficiency, tuning ranges, and the innovative autotuning solution using a microcontroller are discussed, offering insights into overcoming the antenna's narrowband limitations.

Article on portable HF antenna where author diverge about antenna efficiency versus size based on his personal experience on using HF antennas during portable operations

If your multiple transceiver station is suffering of intrastation interference, this handy and inexpensive band pass filters and help you. QST article Sept 1988

A multi section article on learning the morse code for beginners. The article include a list of tips the author consider to be uesful when someone want to begin the trip to learn the morse code.

The document discusses the classifications of sunspots and their potential for solar flare activity, categorizing them into Alpha, Beta, and Delta groups based on their magnetic field characteristics. It explains how these classifications relate to the likelihood of solar flares, ranging from minor to extreme events. The report also outlines the geomagnetic indices and conditions that affect high-frequency (HF) radio propagation, emphasizing the effects of solar flares on radio communication and geomagnetic storms. The information is geared towards amateur radio operators, providing insights into how solar activity influences HF radio operations.

An article on amplitude modulation (AM) operation on VHF bands.

Over 500 downloads indicate _aLog365_ is a widely adopted mobile logbook for amateur radio operators, specifically designed for portable operations. It facilitates callsign lookup, real-time QSO uploads to _HRDLOG.net_ / _Ham365_, and offers CAT control via Bluetooth for radio integration. The application supports various export formats, including ADIF, EDI, CSV, and Cabrillo, ensuring compatibility with other logging software and contest submissions. Key features include an integrated DX Cluster and a DXpedition plan, providing operators with current propagation information and upcoming rare entity activations. A unique Instant QSL (iQSL) viewing capability allows for immediate confirmation of successful radio contacts. The app also supports SOTA, POTA, and WWFF operations, making it a versatile tool for activators and hunters alike. Developed by IW1QLH, the application is regularly updated, with the latest version improving performance and stability, and adding Spanish, French, and German language support.

Make your own dipole for 40 and 80 meters band, assembling standard product parts like 40 meter traps, the 1:1 balun and insulators

This page details (in brief) the component changes to modify a Cybernet series 27MHz CB transceiver to 50MHz.

This page describes an update to a project for a Power and SWR Meter for ham radio operators. The update includes a more powerful microcontroller, increased sampling rate, and improved display options. It explains how to use the new components and provides detailed instructions for building the updated meter. The page also offers alternative display options and includes the full source code for the firmware. Overall, this update enhances the functionality and performance of the Power and SWR Meter project, making it more versatile and user-friendly for hams looking to measure RF power and SWR in their radio setups.

GB3WX - GB3WSX - GB3YS

A home made CW keywer based on the W5UHX board.

List of Worldwide HF Beacons published by RSGB. The beacon service is a vital part of amateur radio propagation knowledge. Updates to the HF list, which is is a heavily edit form of the G3USF list, are continued by the current committee. It now only contains beacons that are known to be active and have been heard recently.