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

Amplitude Modulation (AM) is essentially a mixing process where the audio modulating signal is mixed with the radio frequency carrier

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

Eham users review of Radio Shack PRO-95

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.

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 independent review of the Grundig Yacht Boy 360 portable mediumwave receiver

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

Icom PW-1 1kw Linear Amplifier described by WA0SXV

256 memories enable the _AT-AUTO_ to recall settings across multiple bands, making it efficient for operators who frequently change frequencies. The tuner is compatible with various antennas and amplifiers, such as the Mercury LUX, and integrates seamlessly with radios like the FLEX 6400 using an RS232-USB connection. This integration allows the tuner to follow frequency changes without additional input, enhancing operational efficiency. Despite being out of production, the _AT-AUTO_ remains supported by Kessler Engineering, which offers firmware updates and repair services. The tuner features a cross-needle SWR meter, providing quick visual feedback during tuning. It also includes a QRO keyline circuit to protect amplifiers during tuning. Users appreciate the tuner's ability to track radios via CAT control, avoiding automatic tuning during QSOs, a common issue with other models. The _AT-AUTO_ is praised for its durability and performance, with many users noting its reliability over years of use. Its ability to handle legal limit power and its balanced line output make it a versatile choice for serious operators. Although it lacks some features like multiple coax outputs found in other models, its robust build and continued support make it a valuable tool for HF enthusiasts.

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 review of the Alpha 87-A power amplifier by WD0M

Yaesu FT-450D HF / 6 Meter DSP Transceiver, a nice affordable transceiver for amateur radio use, but understand the caveats.

A review of the GAP Challenger DX Antenna that is not a traditional 1/4 wave vertical, but is a vertical dipole, this gives it several advantages over a standard 1/4 wave vertical, mainly the reduced number of radials, with excellent performances.

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?

eHam reviews of the RM VLA 200 VHF RF power amplifier

eHam.net reviews of the Icom IC-R20 wideband receiver

The MiniPA Linear Amplifier for HF page discusses the popularity of QRP for HF among ham radio operators, such as those using the Yaesu FT818 or low power SDR transceivers. It explores the use of cheap kits from eBay or Chinese suppliers to build a 70-100W SSB amplifier using IRF530 MOSFET transistors. The article provides a review of the MiniPA design, including its features, components, and assembly process. It also highlights the importance of using a heatsink and forced air cooling for optimal performance. This page is useful for hams looking to enhance their HF rig with a budget-friendly amplifier.

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

A review of the SteppIR UrbanBeam antenna a two element Yagi antenna working 40-6 meters. The UrbanBeam is a good choice for those thare are limited by lot size, regulations, city regulations.

Documents the _5W0M_ DXpedition to Samoa (IOTA OC-097) conducted by a German team from April 4th to 18th, 2013. The resource provides operational details and insights into activating this Pacific entity. It covers the planning, execution, and on-air activities of the multi-operator team, focusing on maximizing contacts across various HF bands. The expedition successfully logged over **30,000 QSOs**, providing DXCC credit for many operators worldwide. The site serves as a historical record, allowing hams to review the expedition's progress and understand the logistical challenges of operating from a remote island. It highlights the strategic band choices and operating techniques employed to achieve a high QSO rate and reach diverse geographical areas.

eHam users review of the Icom IC-R75 receiver

eHam reviews of the Icom IC R7100 VHF UHF receiver

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

Reviews of the Icom ID-51A handheld dual band transceiver

eHam reviews of Alpha 8410 HF power amplifier

A detailed review of the Icom IC-7700 by VA7OJ/AB4OJ

This PDF document reviews the POTA PERformer Antenna by KJ6ER, providing insights and details about its performance and features. The content is aimed at hams looking for information on this specific antenna model to help them make an informed purchasing decision. It contains technical specifications, user experiences, and possibly recommendations for optimal use. The review is valuable for hams interested in portable operation and seeking a reliable antenna solution for Parks on the Air (POTA) activations.

A review of the dual band FT-8800R transceiver by the jeep expedition group

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.

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

Review of the 144/430 MHz Dual Band FM Transceiver by Yaesu

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.

The Ontario QSO Party (OQP), an annual event, takes place on the third full weekend of April, specifically from 1800Z April 18 to 0300Z April 19, 2026, and 1200Z to 2000Z April 19, 2026. This **QSO party** encourages stations outside Ontario to contact as many Ontario amateur radio stations as possible, while Ontario stations work both in-province and worldwide. Key rule changes for 2026 include phone QSOs now counting equally with **CW** QSOs (2 points), the introduction of VE3RHQ as a bonus station, a 250m county line proximity definition, and a new Fixed County Line Category, alongside an adjustment of contest times. Established in 1998 by Bob Chandler VE3SRE, the OQP has been managed by Contest Club Ontario (CCO) since 2006. The event contributes to the State QSO Party Challenge, offering various award categories and maintaining records of past performance. Participants can submit activation plans, review Ontario multipliers, and access county maps. Final results and certificate winners are published, and a dedicated groups.io discussion group facilitates community interaction and support for logging software.

Yaesu FT-7800R dual band mobile transceiver reviews

eHam reviews of the TE Systems 1452G 2m mobile power amplifier

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

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

eHam reviews about the Wouxun KG UV8D V/UHF Handheld Txcvr - Dual reveive 135-175 MHz & 400-520Mhz

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

eHam reviews of the MFJ-259B HF/VHF Antenna Analyser

A review with early observations and technical data specifications of the Icom IC-703 QRP HF+50 MHz transceiver

WSJTX-Controller-v2, or Otto, functions as an assistant for the WSJT-X amateur radio program, specifically designed to enhance operational efficiency for weak signal digital modes. The software automates several key tasks, including call management, prioritizing DX stations based on user-defined criteria, and optimizing frequency selection within the WSJT-X interface. It requires a modified version of WSJT-X to function correctly, integrating directly with its core processes to provide augmented control. Otto supports various digital modes, facilitating auto-logging of contacts and generating specific alerts for desired stations or conditions. It is engineered to streamline the workflow for operators engaged in DXing and general weak signal communication, offering features like automatic CQ responses and intelligent band monitoring. The utility is not compatible with certain other amateur radio software and is explicitly noted as unsuitable for contest operations or the WSJT-X Hound mode, indicating its specialized focus on non-contest DX and casual operating. The project's GitHub repository provides the source code and documentation, allowing users to review its implementation and contribute to its development. The software's design emphasizes automation to reduce operator intervention during routine digital mode operations.

Web site dedicated to articles relating to Ham and CB Radios and antennas, reviews and classifieds.

Txtopia provides a browser-based Morse code translator that converts plain text to International Morse Code and decodes Morse back into text, supporting various Unicode dot and dash representations. The tool automatically detects translation direction, normalizes common input variations like middle dots (·), bullets (•), em dashes, and underscores, and explicitly flags unsupported characters or ambiguous sequences with visible placeholders rather than silently dropping them. It accepts spaces, tabs, newlines, and pipes as letter separators, and slashes or blank lines for word boundaries, recording collapsed separators for user review. Users can adjust playback speed from 5 to 40 WPM and tone frequency from 300 to 1000 Hz for CW practice, with playback adhering to international Morse timing. The application operates entirely client-side, ensuring user input remains in the browser without server transmission. It includes a comprehensive reference for the supported Morse alphabet, numbers, and punctuation, aiding in learning and verification. The tool is suitable for checking game clues, verifying tattoo designs, and transcribing messages for ham radio CW practice.

Review of Ameritron AL-82 HF amplifier, owned for three years now, and over that time, it has given me incredible performance on all bands. Inclueds a comprehensive usage report and a summary on Pro and Cons of this amateur radio RF amplifier

eHam user's review of the Icom PW-1 RF Power Amplifier

Review of the excellent ICOM IC-R8600 Wide Band SDR communications receiver. Featuring Direct Sampling SDR below 30 MHz Hybrid Superhet / SDR above 30 MHz.

These pricey battery-powered devices are the only type of generator that can be used indoors safely. The article reviews pro and cons of power stations evaluating runtime, power delivery, power quality, ease of use, and noise.

Review of Yaesu VX-3R 2 m/70 cm FM transceiver. Receives 0.5-999Mhz AM/FMN/FMW, Transmits 144-148 and 430-450Mhz VHF/UHF FM.