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Ramblings on amateur radio, flying, programming, martial arts, the Macintosh and who knows what.

Tips and tricks for succesful soldering. An illustrated guide for beguinners and an usefull reminder for expert in soldering.

Icom IC-703 HF + 50 MHz transceiver, english official instruction manual available in PDF File to download.

Diamond W8010 Multiband Dipole Modifications

Accurate meteorological data is crucial for optimizing antenna performance, predicting propagation, and ensuring safe tower work. This resource provides a curated inventory of weather stations, including models like the _AcuRite Atlas_ with lightning detection and the _Ambient Weather WS-2902_ WiFi Smart Weather Station, which offer real-time data on environmental factors. The product listings detail specific features such as direct-to-Wi-Fi connectivity, rainfall tracking, and temperature insights, enabling informed decision-making for various amateur radio operations. The platform categorizes products by application, featuring weather stations tailored for home and backyard use, as well as more robust systems for farm and agriculture, which can be critical for field day operations or remote station monitoring. It also highlights _Made in USA_ options, emphasizing local manufacturing and support. Beyond weather instruments, the site also presents related surveillance technology, such as the _Waggle solar CCTV camera_, designed for outdoor reliability with an IP65 weatherproof rating. This integration allows for comprehensive monitoring of remote ham radio shacks or antenna sites, combining environmental data with visual oversight.

When a broadcast antenna is to be placed on top of a building, there are special problems of feeding and grounding. The radiator is usually electrically short, that is, much less than one-quarter wavelength high.

The N0QBH QRSS project page, a couple of projects using available kits for improved frequency and timing stability. A configurable DDS VFO 100mW transmitter with LCD display and a modified Hans Sommers 40m 100mW transmitter

Soldering Tips and tricks by George Szymanski, DU1GM

A 15-pin data switch, typically a rotary-knob type designed for DB-25 connectors, forms the basis for this microphone selector project. The resource details the conversion process, which involves replacing the original DB-25 connectors with **RJ-45** or **RJ-12** jacks to accommodate modern amateur radio microphones. It specifically addresses wiring for radios like the Icom IC-706 series (including the IC-7000 and IC-703) and Yaesu transceivers such as the FT-857, FT-897, FT-817, FT-7800, FT-7900, FT-8800, FT-8900, FTM-100, and FTM-400. The design ensures all microphone lines are switched straight through, with separate contacts for external speaker/headphone jacks, allowing simultaneous switching. The project emphasizes the practical application of switching between a headset for net control and a hand mic for rag-chewing without repeatedly plugging and unplugging cables. It highlights modifications to the original concept, such as eliminating a separate PTT jack by integrating PTT into headset cables and building the external speaker cable directly into the selector. The article provides guidance on managing the non-color-coded wiring often found in these data switches by soldering wires one by one from old to new connectors, ensuring correct pin alignment. This approach simplifies the conversion, making it accessible for hams seeking a functional and cost-effective mic switching solution.

Have you measured the SWR at the antenna?

Delta Electronics Manufacturing, a global manufacturer, specializes in _RF connectors_, adapters, and cable assemblies, providing custom interconnect solutions with superior performance. Their Advanced Vertically Integrated (AVI) global facilities emphasize efficiency, quality, flexibility, and cost control across their product lines. The company serves diverse industries, including broadcast and audio, test and measurement, military, aerospace, and public safety communications. For instance, Delta supplies RF interfaces for military aircraft, satellite launch vehicles, and missiles, maintaining a long-standing QPL supplier status. Their field-tested RF interconnects are also crucial for two-way radios, base station equipment, and antenna systems in public safety applications, ensuring reliable performance in critical communication infrastructure. Delta's solutions extend to commercial aircraft and semiconductor manufacturing, where their RF interconnects power etch equipment, deposition equipment, and chip testing systems worldwide.

The RBN S-Meter visualizes real-time HF propagation data from the Reverse Beacon Network (RBN). It processes thousands of automated spots per hour, providing a real-time picture of active RF paths on HF bands. Users can set their vantage point using _Region Mode_ or _Grid Square Mode_. Region Mode allows selection from broad geographic areas like E. North America or Europe, while Grid Square Mode uses a Maidenhead grid square and radius for more precise data. The app displays eight region panels, each with horizontal bars for bands 160m through 6m, indicating signal strength with a color ramp from green to red. A dimmer trail shows peak hold values, and an S-unit readout provides additional detail. The app is a free web application accessible on any device, offering a practical tool for ham radio operators interested in CW, RTTY, and FT8 signals. It features a Progressive Web App installation option for enhanced usability on mobile and desktop platforms. Users can install it on Android, iOS, and Windows devices, providing a native app-like experience. The app replaces the previous Windows standalone executable, incorporating user feedback to improve features like grid square mode and automatic location detection.

_AT Auto_ is an automatic antenna tuner designed for amateur radio enthusiasts seeking efficient and reliable tuning solutions. This device automates the tuning process, allowing operators to focus on communication rather than manual adjustments. The tuner is compatible with a range of transceivers, enhancing its versatility in different shack setups. Its design incorporates advanced circuitry to ensure optimal performance across various bands. The _AT Auto_ tuner is particularly useful for those operating in HF bands, providing seamless transitions between frequencies. Its integration capabilities with other shack automation products make it a valuable component for modern amateur radio stations. The tuner supports multiple modes, including _SSB_ and _CW_, catering to diverse operating preferences. Its robust construction and user-friendly interface contribute to its appeal among both seasoned operators and those new to the hobby. Kessler Engineering's focus on innovation and quality is evident in the _AT Auto_'s design. The tuner is part of a broader product line that includes shack automation solutions, reflecting the company's commitment to enhancing amateur radio operations. Despite the website redesign, the tuner remains a key offering in their product portfolio.

Hot Springs Village AR

W8TN article on repairing an Alpha 87a power amplifier

The K5BSA Venturing Crew 73 resource, intended for a ham radio club based in Richardson, Texas, currently presents a 404 "Page Cannot Be Found" error. This status indicates the original content, which likely detailed club activities, membership information, or amateur radio projects, is no longer accessible at the specified URL. The page provides general information about _QSL.net_ hosting services, noting it supports over 30,000 websites for amateur radio operators and organizations. The error message suggests contacting the website owner directly or using an internet search to locate the intended content. It also clarifies that QSL.net cannot assist in finding specific missing pages hosted by individual users, as each site is independently maintained. The platform offers its email and web services without cost to the amateur radio community. Despite the error, the page includes links to general QSL.net resources such as "About QSL.net," "The Help Page," and "EMail Mailing Lists." It also features a prominent "Make a Donation" option, emphasizing that while services are free, user contributions are encouraged to support the hosting infrastructure.

A multi-band off centre fed dipole, designed to operate on all bands from 40m (7MHz) to 6m (50MHz). Author claims it will operate on 40, 30, 20, 17, 15, 12 and 10m without an ATU (SWR <3:1) plus 6m with an ATU.

This resource, despite its title, does not provide information relevant to amateur radio operations or the W1BD Central Vermont Amateur Radio Club. Instead, the content focuses on commercial topics such as vinyl lettering, business signage, and brand recognition strategies. It details the application of _transfer tape_ for graphics, the importance of pre-masking in vinyl cutting, and the use of squeegees for smooth decal application. The site also discusses various types of business signs, including monument signs and awning signs, highlighting their role in attracting customers and establishing brand presence. Further sections delve into home maintenance tasks like gutter cleaning, offering advice on using power washers and the importance of safety measures when working on ladders. The content also explores strategies for building brand recognition and customer loyalty, emphasizing consistent marketing efforts and excellent customer service. It touches upon the use of custom-printed bags and digital displays, such as LED signs, for enhanced visibility and engagement. The site's articles include practical tips for kitchen renovations, such as upgrading cabinet hardware, adding pendant lighting, and repainting cabinets to achieve a fresh look without significant expense. The content is entirely unrelated to amateur radio activities, club information, or technical aspects of radio communication.

A document describing the reparing and restoration of an old Heathkit SB-101 power amplifier

This article is about two excellent small helical antennas for the two meters band. With performance close to that of full sized antennas, these small helical antennas are low in profile but high in efficiency.

Welcome to our line of Low Frequency, Natural Radio Research, Broadcast, Marine and Shortwave products. Our evolving product line is the result of our dedicated research efforts primarily in the areas of LF, VLF, MF, and HF.

If you thought you knew everything about balun performance characteristics, there is an important figure of merit you may have neglected

A tutorial on setting up a Low Cost QRP (FT8, JT9, WSPR etc) Monitoring Station with an RTL-SDR V3 and Raspberry Pi 3

Homemade a custom programming cable that can works with Kenwood TM-V71A or TM-D710A

A blog dedicated to military communications shortwave intercepts, sponsored by the Teak Publishing

Drake Radio Service & Repair, Refurbishing Services

Multi-sensor real-time temperature monitoring and logging system using Arduino

The project in this article illustrates how to do this in a simple and low cost way so that you can easily access the microwave bands using the existing HF or HF/VHF transceiver as IF.

Replacement high voltage metering resistors procedure

Complete microphone wiring handbook for most popular radio transceivers provided by Astatic Microphones.

Complete plan for making a 2-meter J-Pole antenna. This drawing in PDF File includes a detailed list of the parts needed to assemble the Jpole antenna for 144 MHz.

Have you been looking for an easy way to measure power or SWR at 1296 MHz? One thing is certain, it is not easy - simply because the normal range of SWR meters that most of us have is not up to 1300 MHz.

Calculate distance, bearing and more between Latitude/Longitude points. This page presents a variety of calculations for lati­tude/longi­tude points, with the formulas and code fragments for implementing them.

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

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.

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

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.

Microwaves101 provides an extensive repository of information covering fundamental principles of microwave design, targeting engineers and radio amateurs interested in the higher frequency spectrum. The site features a detailed _encyclopedia_ of microwave terms and concepts, alongside practical design considerations for various components and systems. It serves as a foundational reference for understanding RF propagation, transmission lines, and active/passive microwave circuits. The resource includes numerous calculators for impedance matching, filter design, and other critical RF parameters, facilitating hands-on project development. Discussions on **10 GHz** equipment and **24 GHz** projects highlight practical amateur radio applications, extending to operations up to 134 GHz. Content spans from basic theory to advanced topics like MMIC design and antenna characteristics, supporting both educational and practical endeavors in microwave technology.

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

The goal of this interesting project is to monitor a particular set of frequencies for a set period of time. In this article your will find instructions to build and operate an all-band WSPR node using cheap hardware and free software. At the end of this you'll have a Raspberry Pi, connected to an RTL-SDR dongle that monitors all of the WSPR frequencies rotating randomly every 15 minutes.

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.

Operaring portable during field day by VK4ADC

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.

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

Repairing a KAM interface changing two capacitors and transistors by IK5PWC

The basics of through-hole soldering, the tools needed, go over techniques for proper soldering.

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