Maquina do Tempo
Amateur radio site from Brasil
A portable 3 element 6m Yagi
Antennas/6M/6 meter Yagi Antennas
A small Yagi antenna for camper van. It is made of aluminum tubing, breaks down for storage, and works well for communicating with others. He built it in an afternoon and it gets good signal. The antenna is lightweight and can be packed up to fit inside his van while traveling
QRP Cluster
DX Resources/Clusters
QRP self spotting Cluster, where every QRP broadcasting enthusiast can announce on which frequency they are working, in which mode, or with what equipment and power they are working.
QSL Card creator
Software/QSL
This webpage allows you to create custom QSL cards (confirmation of radio contact) as PDFs for printing. You can personalize them with images and information. The cards are standard size (5.5" x 3.5") but can be adjusted slightly for easier printing on regular paper. You'll need Adobe Acrobat Reader to view the PDFs. There's also an option to create a free account to save your information for future cards.
K4SWL Antenna Plus
Antennas/Portable
This project details building a multi-band antenna for park activations. The author constructs a random wire antenna with a 9:1 UnUn for improved performance. Winding the toroid core proved challenging, but the completed antenna shows promising results in initial tests with an analyzer. Further field testing is planned for a future activation.
Beverage Remote Switch
Technical Reference/Antenna Switch
The author describes building a remote switch box to control the direction of two reversible Beverage antennas. The switch uses a buried cable and relays to select the desired antenna direction from the shack. The design is simple and uses common components.
2024 ARRL Field Day Poster Released
A poster promoting 2024 ARRL Field Day has been released on the Field Day web page, www.arrl.org/field-day. The two-sided informational poster features this year's theme "Be Radio Active". It includes a space for clubs to fill in information about their planned activation so that members of their community can come visit the site. More resources for promoting 2024 ARRL Field Day are being develo...
An Overview of Beverage Receiving Antennas
Antennas/Beverage
This article explores Beverage antennas, a type used for low-frequency radio reception. Despite the mystique, they are relatively simple wire antennas placed near the ground. Their key benefit is improved signal-to-noise ratio by rejecting unwanted signals. While lengthier antennas offer better reception, even shorter versions (around 200 feet) can improve DX reception compared to traditional antennas.
Top Amateur Radio Websites - Issue 2414
DIY EMC/RFI Mains Filter for a Clean Shack, G4WIF End Fed Half Wave Antenna , Antennas for QRP Operation, Innovative 2m to HF Converter, Exploring the Spectrum From HF to UHF Frequencies, Boondock Echo 2 way ham radio recorder, Building an Enhanced APRS IGate with Debian 12 and Raspberry Pi, CB0ZA Robinson Crusoe Isl DX Pedition,
Register Now for the 2024 ARRL Youth Rally!
As part of the fun at Dayton Hamvention®, youth attendees are invited to participate in the 2024 ARRL Youth Rally on Saturday, May 18. The day will include a special agenda of activities and presentations intended to engage and inspire young hams and young newcomers to amateur radio. The Youth Rally is intended for students who are 11 to 21 years of age. While Hamvention offers free tickets for ...
ARRL Seeking Applicants for Assistant Education and Learning Manager
ARRL is working to engage the next generation of radio amateurs right in the classroom. Many young people have become active hams because of the ARRL Teachers Institute on Wireless Technology. This donor-funded effort brings teachers from across the United States together to get them excited about radio through hands-on experiments. The Institute then trains them on how to take that excitement b...
Repairing a dead Kenwood TS-850S
Radio Equipment/HF Transceivers/Kenwood TS-850
The author fixed a friend's Kenwood TS-850S radio, which suffered from Capacitor Plague, a common problem in 1990s electronics where capacitors leak and damage circuit boards. The CAR board, responsible for generating signals, was especially affected. The author cleaned the board, replaced the capacitors, and repaired a broken trace. Although the radio mostly functioned afterward, the "Slope Tune" control behaved abnormally. The cause seems to be a software issue, not a hardware one.
ARRL Audio News April 5, 2024
ARRL Audio News April 5, 2024
Ham Radio's Many Roles During Solar Eclipse
In one of nature's most spectacular visual displays, on April 8, 2024, the sun will align with the moon and the Earth, casting a shadow that will transit much of North America. Spectacular Display and Gathering Millions will gather along the path of totality - the section where the sun is fully blocked by the moon - to witness something that happens, on average, once every 375 years for any place...
Multi-Band End-Fed Antenna Design for Limited Space
Antennas/End-Fed
This document details the construction of a multi-band end-fed antenna, suitable for situations with limited space for larger antennas. The design utilizes a 1:49 to 1:60 impedance transformer to match a half-wave wire antenna fed at one end. Compared to a traditional dipole, this antenna resembles a highly unbalanced Windom antenna with one very long leg and a virtual short leg. The design eliminates the need for radials but relies on the coax cable shield for grounding. The document recommends using at least 10 meters of coax and installing a common mode filter at the entry point to the shack for improved performance.
Reversible 40 Meter Moxon
Antennas/40M
The author wants a compact, switchable antenna for 40-meter ham radio. They compare 3 designs: rectangle, short-tipped W6NL, and T-hat. All work well electrically, but mechanics matter for a large antenna. The rectangle needs strong support, while the T-hat is sturdier with slightly longer elements. The T-hat design wins for now, but the author will focus on its mechanical details next.
Reducing RFI from PoE Devices
Technical Reference/Radio Frequency Interference/Noise Reduction
Hams can be annoyed by noise from PoE cameras and access points. These devices and their long cables act like antennas, picking up and spreading unwanted radio signals. By wrapping ferrites around the cable will reduce this noise. It won't silence it completely, but it can make a big difference.
Beverage Lightning Protection
Antennas/Beverage
The article describes adding lightning protection to Beverage antennas, which are long wires susceptible to lightning strikes. The author reviews common lightning protection circuits and discusses their components. They then detail their design based on existing methods, highlighting choices for components and reasoning behind them. Finally, the author presents the completed design and its implementation on their Beverage antennas.
The Reversible BOGs
Antennas/Beverage
The author struggled with receiving antennas on his property. After a standard Beverage on Ground (BOG) antenna failed, he built a Reverse Beverage on Ground (RBOG) using telephone cable. He details construction and testing, finding the RBOG outperformed other antennas in noise level, signal strength, and reception pattern. Software modeling helped optimize the antenna length. Unfortunately, the project ended when telephone cable from the second RBOG was stolen.
40 meters band beverage antenna
Antennas/Beverage
The author describes his experience building and using a Beverage antenna for the 40-meter band. Despite encountering some challenges, the antenna offered some improvements in receiving stations compared to a 3-element inverted Vee antenna. The Beverage antenna showed a significant daytime signal-to-noise ratio improvement and received signals better than the Vee antenna. However, the front-to-back ratio was not ideal, and the transmit power seemed to affect the Beverage antenna. Overall, the author concludes that the Beverage antenna might be more suitable for locations with higher noise levels. The total cost of the antenna was around 30 Euros.
Beverage Transformers for HF Receiving Antennas
Antennas/Beverage
This FAQ covers building and buying transformers for loop-on-ground and Beverage antennas. Building one uses ferrite cores and thin wire. Buying is an option, with the DX Engineering BFS-1 being recommended. These transformers isolate the antenna from the cable to prevent unwanted signal pickup.
FunCube Dongle HF Upconverter: Expanding Reception Range
Operating Modes/Satellites/CubeSats
This article describes an HF upconverter for the FunCube Dongle Pro. Designed for radio amateurs, the converter extends reception capabilities to lower frequencies (0 Hz to 30 MHz) by mixing them with a higher oscillator frequency (100 MHz). This translates the desired signal into a range detectable by the FunCube Dongle (64 to 1,700 MHz). Key components include a double-balanced mixer and a low-pass filter to suppress unwanted signals. The project provides schematics, filter specifications, and design considerations for construction.
Creating a Custom IC-705 Paddle Mount
Radio Equipment/HF Transceivers/Icom IC-705
This article describes a DIY paddle mount for the Icom IC-705 radio. Dissatisfied with the high cost of commercial options, the author builds a mount from sheet metal and scrap materials. Construction utilizes hand tools and readily available supplies. The final design offers adjustable paddle placement and tool-free installation/removal. Initial testing shows promise for improved field operation.
QLog
Software/Logging
QLog is a free log book program for Amateur Radio users that works on Linux, Windows, and Mac OS. It's made with the Qt framework and uses SQLite for storing data. QLog tries to keep things easy to use while offering all the features you'd need in a logbook. It's not meant specifically for contests at the moment.
Top Amateur Radio Websites - Issue 2413
Budget-Friendly 5-Element Quad Antenna Design, Budget-Friendly QRP T-Tuner and SWR Bridge, A Guide for Seamless FT8 Operation - Time Sync, Building a Robust PL519 Tube HF Amplifier, GMA Maps, Adapting Standard Headset Mic for Yaesu FT-8900, Portable Efficiency: Building a KX3 Go-Box,
ARRL Audio News March 29, 2024
ARRL Audio News March 29, 2024
Amateur Radio Importance Highlighted at National Hurricane Conference
The National Hurricane Conference was held March 25 - 28, 2024, in Orlando, Florida. Amateur radio was well represented at the event. A series of workshops were held that focused on amateur radio's involvement in hurricane tracking, coverage, and recovery. Among the presenters was the Assistant Amateur Radio Coordinator of WX4NHC at the National Hurricane Center (NHC) Julio Ripoll, WD4R. Ripol...
New Training Course Offered by the ARRL Puerto Rico Section
The ARRL Puerto Rico Section has a new online training course for prospective amateur radio operators. Fifty-three students have enrolled in the course, taught by ARRL Technical Coordinator and Instructor Carlos Roig, WP4AOH, who draws from the ARRL License Manual and the National Conference of Volunteer Examiner Coordinators pool of questions for the Spanish Zoom course. The course is open to ...
World Amateur Radio Day is April 18, 2024
World Amateur Radio Day (WARD) is celebrated each year on April 18. The theme for 2024 is, "A Century of Connections: Celebrating 100 Years of Amateur Radio Innovation, Community, and Advocacy." The global event covers all of the International Amateur Radio Union (IARU) regions and spans 2 days: Thursday, April 18, 2024, 0000 UTC to Friday, April 19, 2024, 0000 UTC. On April 18, 1925, the IARU wa...
Southeastern Repeater Association (SERA) President Wade "Danny" Hampton Jr., K4ITL, passed away February 28, 2024.
While attending the North Carolina State School for the Blind (now known as Governor Morehead School for the Blind) in Raleigh, Hampton met several sighted friends involved in the amateur radio community and began attending radio club meetings with them. As a result, he became a licensed amateur radio operator at the age of 12, despite the requirement that an operator must be able to read, copy...
QSL Card Generator Online
Software/QSL
This app will generate a QSL card design based on the input paramters as a PDF. Fields marked by a * are required, but the rest are optional. The options at the bottom allow you to customise the look and feel of the QSL card. If you would like, you can also download the LaTeX source file and customise it.
UniBalun: Lightweight Balun/UnUn PCB for QRP Radios (1:1, 1:4, 1:49)
Antennas/Baluns
The UniBalun is a PCB for building a lightweight antenna transformer (Balun) or impedance converter (UnUn) for low power radios. By soldering jumpers and a toroid core, you can create a 1:1, 1:4 Balun or 1:49, 1:9 UnUn. The latest revision (1.2) includes improved pads and supports both BNC and SMA connectors. Build instructions are available for German speakers.
Build a Lightweight 15m Yagi Antenna: Simple Design for Impressive Performance
Antennas/15M
In this article, Steve G0UIH presents a straightforward guide for constructing a lightweight 15m 3 Element Yagi antenna with impressive performance metrics. With a focus on ease of construction and efficiency, the design boasts a nearly 8.2dbi forward gain and 30db front to back ratio. Utilizing readily available materials and a hairpin match for impedance matching, this Yagi offers broad bandwidth and simple tuning for optimal operation across the 15m band.
ARJAN-5 5 band SDR
Technical Reference/Software Defined Radio
This project enhances Arjan te Marvelde's uSDR-pico by integrating a waterfall display feature. By adding an ILI9341 240x320 2.4" TFT display and modifying the software, the goal is to provide a panadapter to the existing transceiver. Initially developed with Visual Studio, the code was later migrated to Arduino IDE for Raspberry Pi Pico compatibility. The focus remains on preserving the original software, primarily enhancing the dsp.c file for waterfall implementation.
Icom 706MK2G Repair
Radio Equipment/HF Transceivers/Icom IC-706
After years of reliable performance, a 26-year-old Icom 706MK2G exhibited an unusual deviation during FM transmission, with the actual frequency being 10kHz off from the displayed frequency. Additionally, the power meter showed a sharp dip during transmission. Upon investigation, it was discovered that the FM VCO voltage adjust variable had become dirty and sluggish over time. By adjusting the variable capacitor and cleaning it with switch cleaner, the issue was resolved, restoring stable power output and accurate frequency transmission.
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