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.
3 Element Quad for 50 MHz
Antennas/6M
A 14.12 dBi gain three elements cubical quad antenna for the six meters band.
This Quad Antenna design page include a MMA model available to download and dimensions for each element.
Top Amateur Radio Websites - Issue 2412
Space-Efficient Excellence: Inverted L Multi-Band HF Antenna, WSJT-X Controller, Introduction to HF Packeteering in the Modern Age, Emergency ham radio frequencies, AI Projections for Ham Radio Modes in 2023-2025, Yaesu ATAS-120A Portable Tripod: Enhancing Efficiency, Mapping the Australian Radio Landscape, FT 1000MP MK V and Keyclicks,
Mastering HF Communication: Decoding Space Weather Data
Propagation/Beginner's Guide
The article enlightens radio amateurs on utilizing real-time space weather data to optimize HF communication. Navigating through Hp30 index, MUF, f0F2, and eSFI metrics, it explains their significance in band selection and propagation forecasting. With essential links and practical insights, enthusiasts learn to discern optimal conditions for high-band DX, low-band DX, and NVIS operations. The author's observations and antenna optimization tips enrich understanding for effective HF operations.
ARRL Audio News March 22, 2024
ARRL Audio News March 22, 2024
Get Ready for the 2024 ARRL National Convention and Youth Rally
A full slate of programming has been committed for the 2024 ARRL National Convention, which will be hosted by Dayton Hamvention®, May 17 - 19, in Xenia, Ohio. Hamvention is the largest annual gathering of radio amateurs in the world. Coupled with the National Convention, this year promises to be a Hamvention not to miss. Building on a yearlong theme to "Be Radio Active," ARRL has planned exhibi...
FCC to Require Two Factor Authentication for CORES Users
The Federal Communications Commission (FCC) has announced an upcoming change to the Commission Registration System (CORES) that licensees use to pay any application or regulatory fees, manage or reset a password on an existing FRN, or request a new FRN. Beginning March 29, 2024, multifactor authentication will be implemented. Users will be prompted to request a six-digit secondary verification ...
International Marconi Day 2024
This year, International Marconi Day (IMD) is on April 27. Italian inventor and electrical engineer Guglielmo Giovanni Maria Marconi was born on April 25, 1874, and is credited for inventing the radiotelegraph system, creating Marconi's law, and sending the first wireless transmission over the open sea. IMD was created to honor Marconi and is hosted annually by the Cornish Radio Amateur Club, GX...
Build a Simple VHF Dipole Antenna for 2 Meters: A Beginner's Guide
Antennas/2M
This article serves as a beginner-friendly guide to constructing a simple VHF dipole antenna for 2 meters, perfect for novices in the hobby. With an emphasis on affordability and simplicity, it explains the basics without overwhelming technical details. Recommendations for coaxial cable and mounting methods are provided, offering practical solutions for effective communication. By following these instructions, novices can build a functional antenna without breaking the bank.
Homebrew uSDX TRX
Technical Reference/Software Defined Radio
The Homebrew uSDX SDR TRX is an experimental transceiver primarily designed for CW and Digital modes due to limitations in meeting FCC requirements for SSB. Developed from the QRP Labs QCX, it incorporates advanced SDR features while utilizing an 8-bit ATMEGA328P. The µSDX community fosters open-source development with various design streams and versions, encouraging collaboration and sharing among enthusiasts.
Prevention and Suppression of RF Interference to Audio Systems
Technical Reference/Radio Frequency Interference
In this study, the author builds upon Muncy's research, demonstrating that radio-frequency current on cable shields affects audio systems through the "pin 1 problem" and shield-current-induced noise (SCIN). An enhanced equivalent circuit for ferrite chokes is proposed, addressing dimensional resonance and inductor self-resonance. Field tests confirm that chokes reduce interference across 500 kHz to 1,000 MHz. Guidelines for diagnosing and mitigating EMI from various sources are provided for product development and field installations.
South Africa - SARL
South African Radio League
Chokes and Isolation Transformers for Receiving Antennas
Antennas/Receiving
Chokes and isolation transformers are essential for receiving antennas to mitigate common mode current, which induces noise and interferes with signal quality. Common mode chokes, formed by winding feedline through ferrite cores, block unwanted current effectively. Proper selection of core material and winding turns ensures resonance near the operating frequency, reducing interference. Isolation transformers further minimize interference, crucial for multi-transmitter stations.
Slovenia - ZRS
Zveza Radioamaterjev Slovenije
Measured Data For HF Ferrite Chokes
Technical Reference/Components/Toroids
FT-240 toroids measurements. The data was measured using well-calibrated HP instrumentation. All plots have been adjusted to a frequency range of 1-100 MHz on the horizontal axis and a resistance/impedance range of 10-1,000 ohms on the vertical axis. This adjustment facilitates comparison among different materials and aids in determining their suitability for use on the HF ham bands.
6O3T Somaliland 2024
DX Resources/DX Peditions/2024 DXpeditions
DX Pedition to Federal Republic of Somalia 2024
A52CI A52P Bhutan DX Pedition
DX Resources/DX Peditions/2024 DXpeditions
SP9FIH as A52P and SP6CIK as A52CI fm Dochula Bhutan ; 40-6m; SSB CW + digital 19th April till 4th May 2024
ARRL Audio News March 15, 2024
ARRL Audio News March 15, 2024
ARRL: Credit Card Processing Available Again
Updated 3/15/2024 at 7:58 PM EDT An update was completed for ARRL by its merchant services provider today. Credit card processing for all services has resumed. Thank you for your patience as we completed the system update. Members and prospective members can again access the following online services: www.arrl.org/join www.arrl.org/donate www.arrl.org/shop Updated 3/15/2024 at 2:37 PM EDT ARRL is wo...
Dayton Hamvention® 2024 Award Winners Announced
The recipients of the 2024 Hamvention Awards were announced on March 8, 2024. Special Achievement Award: Anthony Luscre, K8ZT Luscre is from near Akron, Ohio, and he was first licensed in 1981. He has been a low-power operator, contester, and teacher throughout his amateur radio career. He received his Amateur Extra-class license in 2000. Luscre is active on HF and VHF/UHF, and he operates on ...
Amateur Radio Stands Ready to Support Eclipse Operations
The upcoming April 8, 2024, solar eclipse has many excited about the opportunity to witness the darkness of totality. Spectators from across the country are traveling to the path of total darkness that will stretch from South Texas to Northeastern Maine. Some states are anticipating more than a million travelers for the event. In the impacted areas, schools will be letting students out early for...
2024 ARRL Field Day Theme: Be Radio Active
The theme for 2024 ARRL Field Day is "Be Radio Active." The event will run on June 22 - 23, and it will be one-part contest, one-part emergency communications exercise, and one-part open house -- and a great time. The theme encourages radio amateurs to take advantage of the peak of Solar Cycle 25, which we are nearing. Activity this year is likely to be extremely high thanks to favorable solar ...
Vertical bazooka antenna for the 40m
Antennas/40M/40 meter Vertical Antennas
A quarter wave vertical omni-directional antenna for 7 MHz. Formulas for dimensions in feet and meters are provided. Ideal radial angle is between 35° and 45°. Velocity factor (Vf) varies based on coax type.
Top Amateur Radio Websites - Issue 2411
Portable Half-Square Antenna, The Squid Pole Wire Antenna Re-visited, 50 MHz 300W Power Amplifier, TX5S Clipperton 2024, TX5S Log Online, Efficient 2-Element Quad Antenna for 2m, Propagation on 630 Meters and 2200 Meters, N1FD Nashua Area Radio Society
9M2PJU - Amateur Radio from Malaysia
Amateur Radio Full Disclosure
T32EU Online Log
DX Resources/Logs
On-Line log for T32EU DX Pedition to East Kiribati OC 024
A Simple Morse Code Project: The Tiny Keyer
Technical Reference/Arduino/Morse Code
In his journey to improve Morse code skills, the author developed a straightforward device named the Tiny Keyer using Arduino. Tailored for Morse code enthusiasts and ham radio operators, this project utilized the budget-friendly Arduino ATTiny 85 Kickstarter board. With straightforward setup procedures in the Arduino IDE, the Tiny Keyer's small size and low cost make it accessible for beginners and hobbyist clubs interested in Morse code exploration.
W7EK The Cascade Radio Club
Everett WA
ARRL Headquarters Closed Morning of Wednesday, March 13, 2024
ARRL Headquarters in Newington, Connecticut, will be closed from 8 AM to 12 PM EDT on Wednesday, March 13, 2024, for an employee communications meeting. There will not be a morning W1AW bulletin that day. During the short closure, members are encouraged to use the ARRL website, www.arrl.org, for membership renewals, publication purchases, and to access most benefits, services, and programs.
Spectrogram
Software/Spectrum analyzers
Spectrogram, a PC-based audio frequency spectrum analyzer available from Visualization Software, aids ham radio enthusiasts in aligning receivers like Elecraft K2. Versions are downloadable, with an intuitive interface and customizable parameters. Tutorials by experts like Tom Hammond and John Grebenkemper offer additional guidance.
WSJT-X 2.7.0 Release Candidate 4 available
WSJT-X 2.7.0 Release Candidate 4 has been officially made available to the public. This RC version brings improvements primarily aimed at Fox-mode operators and enhancements to the QMAP companion program.
T32EU East Kiribati
DX Resources/DX Peditions/2024 DXpeditions
13th until 27th March 2024, Kiritimati OC 024, CW and SSB and RTTY and FT8 DX Pedition
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