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The 1/4 wavelength vertical antenna project, initially designed for 20 meters, has evolved into a versatile portable solution covering 10 through 60 meters. K0BXB details its construction, emphasizing a bottom-loaded design with a tapped loading coil and four 10-foot counterpoise wires. The author shares personal experiences and field results, including **18 QSOs** during a park activation on 17m and 30m with 10 watts, and a **2,435-mile** contact with a contest station in Bonaire on 20m using 5 watts. Comparisons are drawn to commercial offerings like the _Wolf River Coils TIA_ and _QRPGuys Triband Vertical_, highlighting the DIY antenna's small footprint, light weight, and ease of tuning for POTA activations. The resource includes insights into using test equipment such as the _NanoVNA_ for SWR optimization and discusses various radiator lengths, from 17-foot wire to a 102-inch whip, demonstrating adaptability for different portable setups. Construction tips cover coil winding, tap placement, and connecting feedlines and radials using common components.

VU4W online log for Andaman Islands DX pedition 2022

Learn how to optimize your keyboard setup for CW contesting in amateur radio. Discover the importance of macros, keyboard combinations, and single keys for efficient contesting. Find out how a mechanical key system like the Lenovo full-sized preferred pro 2 keyboard can enhance your contesting experience. Explore tips on avoiding accidental key presses and maximizing your speed during contests. Dive into macro setup details, including key functions like STOP, CQ, and X. Improve your contesting skills and efficiency with the right keyboard setup tailored for CW operators.

The behavior of a straight dipole and its L-form is examined in terms of impedance and SWR. By adjusting the feed point or bending angle, impedance variation is observed. Impedance shifts symmetrically as the feed point deviates, leading to recommendations for optimal ratios. Model simulations aid in understanding and fine-tuning, crucial for achieving a 50 Ohm match. Practical tuning guidelines ensure efficient antenna performance.

Beam Controller Interface Project. The control system will be via the internet and consist of a Rig-Expert WTI-1 interface which provides access to CAT commands, PTT, and Rx and Tx audio.

Demonstrates the construction of an **ATU-100 (N7DDC)** automatic antenna tuner, detailing the assembly process from component arrival to final enclosure. The resource covers winding the tandem match transformer, connecting the OLED display, and integrating optional control buttons. Specific attention is given to modifying the EEPROM settings for **QRP operation**, reducing the minimum tuning power to 1 Watt, and addressing potential RF interference with CPU by adding capacitors to button connections. The build log includes practical tips such as adapting RG58 coaxial cable strands for PCB mounting and utilizing a repurposed Macbook Pro cover for the custom enclosure. The author references external GitHub pages for comprehensive information, R0AEK's resources for additional details, and a video by MW0SAW for EEPROM configuration across different ATU-100 variants. Future plans involve field testing the completed tuner during SOTA or other portable activations.

Explores the addition of a reflector to the traditional Hentenna design for 6m band, providing construction insights, performance comparisons, and modeling data

Learn how an experienced ham radio operator rebuilt his trap dipole antenna for 30, 40, and 80 meters after a storm damage. Discover the process of upgrading to a short trap dipole for 40, 80, and 160 meters using double-wound traps made from RG-58 coax. Follow along for construction details and tips on building this unique classi.

Learn about Permeability Tuned Oscillators (PTO) and why they are useful for ham radio operators. This page covers the mechanics of PTO tuning, the components involved, and how to wind the PTO inductor. Written by Andrew Woodfield ZL2PD, this resource provides a detailed guide for building and using a PTO oscillator in your amateur radio projects.

Learn how to hack an IR turret to track the International Space Station (ISS) as it passes overhead. Discover the basics of the ISS and how to use simple tools to point an arrow at the ISS without looking at a phone. Find out how to calculate the azimuth and elevation angles to locate the ISS in the sky and enjoy watching this habitable space craft orbit the earth at a speed of 28,000 km/h. Take your hobby to the next level by bouncing radio signals off the ISS or even talking to the astronauts on board. Turn stargazing into an interactive and educational experience with this fun and practical project.

The history of the radio is a fascinating one that changed how the world connected and communicated from distances both far and near. History of the Radio from Inception to Modern Day

A voice keyer for Morse Code written for Arduino

The UV-K5 HF Fullband receive firmware version 0.3 introduces enhanced SSB capabilities using the SI4732-A10 chip. Released separately from UV-K5 CEC firmware, it offers improved HF reception, mode changes, frequency fine-tuning, and user modifications. New PCB designs and detailed usage instructions are included.

If you need a non-standard resistor value you could probably realize a close match using two resistor. If you use two resistor in series it is quite easy to figure out which values give the best match; on the other hand, using a parallel connection it is not so easy (at least for me) to find a good combination. This resistor calculation tool shows which combinations of two resistors (series or parallel) gives a match better than the closest standard value, for the E12 (10%), E24 (5%) and E96 (1%) series.

Come learn why it is very difficult to predict propagation on the top band. Ionospheric Variability, Time Variations of Ionospheric Parameters, Atmospheric Gravity Waves, Ionospheric Absorption and The Role of Negative Ions.

Amateur radio website dedicated to six meters band with dedicated pages on 50MHz propagation and DXing

A blog post about experimenting AI on writing blog post and creating pictures. This page includes also a youtube video by VE4VR experimenting ChatGPT over ham radio bands.

A low-cost Arduino project expanding on the button tutorial, where three inputs act as "buttons" generating Morse code on a WOTDUINO. This keyer, costing around £4, offers learning potential and hints at more complex ham radio applications.

Learn how to enhance your 160 meter reception by building and using a custom band pass filter. Discover how this filter can reduce interference from strong AM broadcast signals, improving the overall performance of your receiver. Find out about the challenges of creating a filter that balances signal loss and attenuation at specific frequencies, and how it can benefit hams operating near powerful transmitters. Whether you're experiencing IMD issues or looking to optimize your 160 meter setup, this article provides practical insights and solutions for ham radio operators.

Assembling a QRP Station for Field Operation

This program simplifies the complex jumper calculations for the PRF1520 radio, which can be a pain to determine manually. It supports common crystal frequencies and channel spacings, advising if a desired frequency is achievable. A recent feature allows determining unknown frequencies of a newly obtained radio by setting the jumper positions and other parameters.

Online impedance calculators grouped by types like Wire inductances, Toroid incuctances, Plane, PAD, Strap inductances, but even Core and Coax Inductances. Air core inductances and mutual inductance groups are also availbale. All these calculators let you input specific paramenters based on the inductor selected and will calculate specific incutance and related dimensions.

This article explains the trick of how to shorten and lengthen pairs of radials to make a 2-band ground plane antenna. Included is a "Table of Multi-Band Possibilities" covering the range of 6 to 40 meters.

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.

Operating amateur radio repeaters involves understanding frequency offsets, CTCSS tones, and the basic signal flow through a repeater system. This resource details the fundamental concepts of repeater operation, including the distinction between input and output frequencies, the role of **CTCSS (Continuous Tone-Coded Squelch System)** for access, and the typical frequency bands utilized for local communication. It clarifies terms such as "simplex" versus "duplex" operation and provides a diagram illustrating the signal path from a handheld transceiver to a repeater and back to another station, emphasizing the range extension repeaters offer. The article further explains practical aspects like identifying a repeater's offset (e.g., +600 kHz for 2-meter band) and the necessity of programming the correct tone. It compares the operational benefits of using repeaters for local communication over direct simplex contacts, highlighting how repeaters overcome line-of-sight limitations. The content is structured to assist new licensees in confidently making their first repeater contacts, providing a foundational understanding of how these critical infrastructure components facilitate wider area coverage for VHF/UHF amateur radio.

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

This project presents a compact QRP SWR meter featuring a 0.96" OLED display (128x64 pixels) for high-contrast visibility, updated with software fixes for display compatibility, improved low-power performance, and support for ATtiny45/85 microprocessors. A 1.3" OLED version accommodates visibility needs. Designed for HF QRP transmitters (3-15W), it uses a Breune coupler with germanium diodes for accurate SWR measurement. Powered by a AAA battery, the meter offers a standalone solution for impedance matching, with a 3D-printed enclosure enhancing portability.

Delta loop antennas, particularly the 30 meter variant, offer unique advantages in terms of vertical polarization and omni-directional coverage. The construction process detailed by VE3VN highlights common mechanical and electrical challenges faced by amateur radio operators. Key design considerations include minimizing interaction with existing contest band antennas, achieving low elevation angles for DX chasing, and ensuring the antenna remains off the ground for agricultural clearance. The article provides specific measurements, such as the loop's height and feed point impedance, which are critical for optimizing performance. The use of NEC modeling software illustrates the importance of accurate resonance calculations, revealing how proximity to the tower affects both pattern and impedance. This practical account serves as a resource for hams looking to build effective antennas while navigating typical construction hurdles.

The K5USS 6 Meter Hentenna Project page on Hamuniverse provides detailed instructions on how to build a 6 meter directional antenna with 3.5 dBd gain. The project is presented with permission from K5USS, Charlie of Richardson, Texas. This directional antenna is a full wave loop on 6 meters, horizontally polarized but mounted vertically, with a 50 ohm impedance, ideal for 6 meter SSB operations. The page is useful for hams looking to construct their own directional antenna for improved performance on the 6 meter band.

This blog post from KA7OEI covers the author's initial exploration into the world of Arduino, a popular open-source electronics platform. The post likely discusses the author's experiences, challenges, and successes with Arduino projects, particularly in relation to amateur radio or other technical hobbies. It may provide insights, tips, or inspiration for hams interested in incorporating Arduino into their own projects. The content is likely informative, personal, and geared towards amateur radio operators or electronics enthusiasts.

Learn about the ZRS QRP-808 kit system for hams from the 1980s. Discover the improved features of the QRP-808 compared to the QRP-805, including the electrical diagram and assembly instructions. Explore the nostalgic journey of building and tuning this iconic amateur radio station, as shared by experienced ham radio operators. See original photos and insights from enthusiasts like Janko S55WT and Mirko S52PC, offering a glimpse into the history of amateur radio technology. Access PDFs for detailed views and immerse yourself in the world of DIY radio equipment construction and tuning.

M2 CW decoder Kit, is an Arduino based morse code decoder, kit produced and delivered by WB7FHC

Repair of a Yaesu FT-1000 MP Mark V probably struck by lightning.

This page discusses the potential risks and safety concerns related to antenna installations for ham radio operators. It emphasizes the importance of following electrical codes and regulations to prevent property damage, injuries, or even loss of life. The author shares personal experiences and advises against using trees for antenna support near power lines. The content serves as a cautionary resource for hams planning antenna setups to ensure safety and compliance with regulations.

Explore VK5DJ's experiments with the si5351a frequency synthesizer, a versatile device capable of generating frequencies from 8kHz to 200MHz. Learn how this I2C configurable clock generator can replace crystals and oscillators in various applications, providing stable and precise outputs. Discover how to program the si5351a for your own signal generator projects and repeater site setups. Utilize the affordable and efficient Adafruit module for reliable performance. Enhance your understanding of PLL/VCXO architectures and fractional dividers for frequency generation. Join the PDS Forum community in experimenting with this innovative technology.

This page discusses the construction and design of a shortened 2-element Yagi antenna for the 40-meter band, focusing on the driven element. The author shares insights on adding hats to the coil to reduce losses and improve performance. The article also mentions the use of EZNEC modeling software and an AIM4170 analyzer for tuning. Amateur radio operators interested in such antenna design and optimization for the 40-meter band can find useful information and practical tips on this page.

The ICOM IC-705, a popular QRP transceiver for portable operations, often presents unique challenges for field deployment. This resource details practical solutions for common portable setup issues, particularly for _Parks on the Air_ (POTA) activations. It describes a custom bracket for connecting antennas to the IC-705 through a backpack's antenna flap, utilizing a BNC female-to-female chassis mount connector to mitigate cable tangles. The author shares experiences with a DIY magnetic loop antenna, noting its ease of tuning with the IC-705 and successful CW contacts on 40 and 20 meters over distances exceeding **1000 miles**. Another modification presented is a strain relief solution for the microphone cord, replacing the standard spring clip with an easier-to-attach method. The page also mentions using a _Wolf River Parks antenna_ for POTA activations and references the QRPGuys DS-1 antenna as another portable option. Firmware updates and integration with an LDG Z11-Pro II auto-tuner are also discussed.

Icom IC-R75 tabletop HF communications receiver came onto the market back in 1999 and was taken out of production in late 2015. Frequency coverage is from 30 hz right to 60 MHz. This allows one to catch the 6 Meter amateur band as well.

Moto-QRP setups offer compact, weatherproof QRP transceivers for portable ham radio use, ideal for motorcycle and backpack operations. The YouKits HB1A MKII, a 5W CW rig, is paired with a lightweight long-wire antenna and an Elecraft T1 tuner for efficient field communication. This setup fits in panniers, enabling operators to explore parks and remote locations. Accessories include a durable Morse paddle, FCC documentation, and essential logging tools, making it a perfect choice for adventurous QRP enthusiasts.

Use of the band as Amateur Radio is secondary in this band to federal radiolocation systems, industrial, scientific and medical devices, federal fixed and mobile systems and the M-LMS. Bandplans for hams. Allocation in 902 - 928 MHz

The purpose of the Moon tracking DLL is to provide an easily used platform for the calculation of the position of the sun or the moon and to provide the associated information often required for amateur radio operators interested in EME. DLL works with any of Windows versions of Delphi, Visual Basic, C and versions.

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.

A simple realization of a panadapter conntected to a custom build IF PanAdapter output added to the Yeasu FT-DX1200. The IF output has been provided by adding a G4HUP PAT board to the transceiver.

Program cooperating with Logger32 and 4 QRZ servers with http method for personal data . Program is very quickly. Correct field QSL_VIA from QRZ , that you can put it on a QSL . Also show if present QSL Bureau for a country de sp9auv

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.

This page provides basic information about SWR (Standing Wave Ratio) and its importance for ham radio operators. It explains what SWR is, how to measure it, and why it is crucial to have a good SWR reading. The content covers the impact of SWR on antenna efficiency, power transmission, and potential interference issues. It clarifies common misconceptions like the impact of coax length on SWR. Suitable for hams looking to optimize their radio setup and avoid performance issues due to SWR issues.

Detailing a Yaesu FT-857 and ATAS-120 installation in a 1997 Toyota Tacoma, the author used Polar Plot to map signal strength. Using a hand truck with a laptop, FT-817, and an Iron Horse antenna, they circled a chalk-outlined 100-foot diameter, revealing potential nulls towards the truck's rear and through the cab, offering insights into antenna performance.

The Beam project offers various features for controlling antenna rotators, including support for 2 or 4 line LCD displays, software or hardware clocks, open collector drives for azimuth and elevation control, and internal calculations for tracking the sun and moon. It can also track satellites and supports "Flip Mode" for inverted antennas. The 4-line version provides detailed readouts while the 2-line version offers a more compact display. New versions now support PWM and I2C H-bridge modes for adjustable speed control at the end of a move.

This page provides a detailed review of the ZB-4, 4 Band CW QRP Transceiver designed for QRP ham radio operations. It includes information on features, performance, and user experience with the ZB-4. The review aims to assist hams in making informed decisions about this transceiver model, highlighting its strengths and potential drawbacks.

A versatile digital VFO design utilizing the Silicon Labs Si5351a oscillator chip and Nokia 5110/3310 graphics LCD display, operating from 1-160MHz with dual VFO capability. This microcontroller-based system, powered by an ATmega328 processor, features rotary encoder tuning, selectable step sizes, RIT control, and comprehensive band memory functions. Drawing less than 40mA at 3.3V, it significantly improves upon previous DDS designs' power consumption while offering advanced features like S-meter display, VFO lock, and programmable BFO/CIO offsets. The design achieves flexible functionality through simple hardware implementation and efficient software architecture, making it particularly suitable for QRP and portable amateur radio applications.