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A complete guide on using the HF amateur radio bands, and the differences with VHF, using filters, influence of solar weather, the split mode and phonetic alphabets.

This article dives into a budget-friendly, DIY antenna option - the multiband half wave end-fed antenna (HWEF). Forget expensive radials; this design uses just wire and a transformer. While the 2012 approach might be dated, it provides a solid foundation for understanding HWEF concepts. Explore how different coil setups can target specific bands (40m, 20m, 10m) for optimal radio communication.

This is a project aboout compact and portable a QRP antenna tuner for use in the HF ham radio bands from 3-30 MHz, even if it's a compact and efficient project this small antenna tuner will not match any possible load.

Thsi article describes a microcontroller driven semi-automatic antenna tuner capable of handling power levels up to 150 watts. The device is a low pass filter tuner manually tuned by setting the optimized L/C combination by hand and then storing the values into the EEPROM of the mictrocontroller to recall them later (seperately for each band from 80 to 10 meters including WARC bands)

A not-for-profit organization incorporated to promote ham radio operation on the bands above 50 MHz in the southeastern United States.

Gimme Five reloaded, a compact 5 band QRP SSB transceiver in SMD technology. This unit covers 5 bands within the amateur radio spectrum (3.5, 7, 14, 21 and 28 MHz). Receiver is a single conversion unit with an interfrequency of 9 MHz. Transmitter uses 5 stages and has got a power level of 10 watts PEP output.

Dipole antennas are some of the simplest antennas to build in addition to being very efficient and solid performers. I wanted to make a simple dipole antenna for QRP portable operation that could be used on multiple bands.

A numbers station, also known as a one-way voice link (OWVL), is a special type of unusual radio broadcast, generally on the Short Wave (SW) radio bands

This project details the construction and testing of a M0PLK Delta Loop antenna for the 20-10m ham radio bands. Inspired by positive reviews highlighting its reduced local QRM compared to Cobweb antennas, the author built the antenna using aluminum tubes, DX-Wire FS2 wire, and a 1:4 balun. A mix of custom 3D-printed parts and careful assembly ensured stability and performance. Initial VSWR measurements met expectations, and test QSOs demonstrated success across multiple bands. Future enhancements include adding a lightweight, remote-controlled rotator for directional capabilities.

This channel is all about radio listening and dxing. I will be covering frequency bands like longwave, AM/MW and shortwave. I'm embarking on my renew interest in this hobby since my childhood.

This guide explores different radio bands that hobbyists use to talk to each other worldwide. It explains how these bands work and what they're used for. From low-frequency to high-frequency bands, each has its own unique features for people who enjoy communicating through radios

The KGD antenna is an option for those with space restrictions. The idea behing this project is to provide a short dipole antenna for HF Bands and to allow operations on HF bands when its not possible to setup large antennas, using these short base loaded dipoles.

Personal web site by Joe PS8ET an active amateur radio operator from Brazil very active both on HF bands and on Ham Radio Satellites.

F5NPV explores the construction of a cost-effective 1KW dummy load for radio enthusiasts. Purchasing a commercial dummy load can be expensive, but with basic materials such as a metal can, resistors, mineral oil, and a heat dissipator, you can build your own. The article provides a simple guide to assembling the load, including the importance of testing for inductance. The DIY dummy load yields impressive performance, with an SWR of 1.2:1 across multiple bands and the ability to handle up to 1KW of power. This budget-friendly solution is a valuable addition to any radio shack.

The ICOM IC 7300 SDR radio has a very nice receiver for ham bands, but outside these bands the reception is not 100% reliable. This is due to the ADC aliasing phenomena of SDR receivers.

This is the mobile version of the DK0TE WebSDR providing HF ham radio bands coverage.

A table that summarize all known amateur radio emission modes, with reference to software and platform available for digital modes

OpenWebRX online radio receiver from Olsztyn Poland 10-15 meters bands, 50 MHz VHF UHF bands.

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.

Amateur Radio enthusiasts who are interested in the LF and MF bands may be familiar with WSPR and WSJT JT9. Used as a propagation probe or beacon, WSPR allows very weak signals to be detected, frequently as weak as -27dB SNR.

A new SDR radio concept developed by N6QW as an experimental 5W SDR transceiver for the 40 meter bands. Radio and Rig (RADIG) is a term conied by the author.

Choking balun for lower HF and MF bands. (1.8MHz - 10MHz). Requiring a choking balun to isolate the potential RF pick up on the coax cable as it runs past equipment such as computer within the radio room at lower HF and MF frequencies a simple method of winding RG58 coax onto a Powdered Iron Toroid Core was constructed.

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

Utilizing snap-on ferrite cores and practical insights, the author enhances their shack's cleanliness against electromagnetic interference. With meticulous experimentation and installation, they improve noise levels across HF bands, reflecting on the effectiveness of their filter in minimizing common-mode disturbances. Updates underscore ongoing refinement and cautionary advice for optimal filtering and radio reception amid changing RF environments.

A ham radio home made preamplifier for 50 MHz and 70 MHz bands

DXSPOTS is a Telnet connection program. It allows radio amateurs with a lot of DX traffic to know instantly the status of the bands and to know which DX are currently on the air. Following the Packet-Clusters where data was transmitted on VHF/UHF via dedicated relays and sometimes on HF at a very low speed (300Bds on HF), the Internet has taken over and is now transmitting DX information via the computers in most shacks. Translated with www.DeepL.com/Translator (free version)

This article presents an innovative homebrew antenna design utilizing surplus ladder line as a receiving antenna for HF and MF bands. The Ladder Line Antenna (LLA) transforms standard 450-ohm ladder line into a directional, bidirectional, or omnidirectional antenna system through different termination methods. The design, which requires minimal space and height, achieves 6-10dB front-to-back ratio on 40-160m bands using a 33-foot length. This DIY wire antenna project offers an efficient, low-profile solution for amateur radio operators, featuring broadband operation without ground radials and easy installation below fence height.

Modification to an old cellular phone base station modules, with a fairly reduced output power (10 watts or so), the stock power amplifier modules will cover the 2.3 GHz and 2.4 GHz amateur radio bands.

The "DIY Telescopic-V Antenna £35" project showcases the creation of a budget-friendly, portable telescopic V-shaped antenna inspired by commercial designs. Using eBay-sourced telescopic whips and custom mounting solutions, the author documents their process, testing, and adaptations. Despite challenges like weather and missing tools, the antenna performed well across multiple bands, enabling successful QSOs. Future improvements include exploring loading coils and testing in better locations. The compact design offers versatility for amateur radio enthusiasts seeking an affordable and practical solution.

Construct the Peaberry, a SoftRock-compatible SDR transceiver. This project is aimed to build an amateur radio transceiver that operates on the medium or short wave bands

Extended Double Zepp measurements for all ham bands, and online calculator. The antenna is constructed much like an ordinary Dipole antenna but with 5/8 Wavelength Elements matched with an added Impedance Matching Section of balanced feed line

HF digital mode transmissions, voice transmissions in HF and VHF Bands collected in several XLS files by Relic Radio communications

Transformers can be used as part of a hybrid combiner or as phase inverters for an RX antenna array.

A basic introductionto APRS on HF Bands for radioamateurs and how to setup an APRS tracker using Argent Data Systems T3 Mini TNC device, configured and assemble ready for portable operations.

The J-Pole antenna is a common omnidirectional antenna used in amateur radio, particularly on the VHF and UHF bands. This article is an attempt to explore how the J-pole antenna transforms feed-line impedance to free-space impedance, all the while providing gain found only in the more expensive commercial products.

This article describes the construction of a three-band vertical antenna for the WARC bands (10, 18, and 24.9 MHz). Unlike a previous design using thin wire requiring a complex matching device, this version uses a telescopic set of pipes, reducing reactances and simplifying the matching device to two coils and two capacitors. The article provides details on the antenna model, the matching device circuit, and tuning methods, including the use of frameless coils and variable capacitors. With proper tuning, the antenna achieves a VSWR not exceeding 1.3 across all bands, demonstrating a practical and efficient design for amateur radio enthusiasts.

Get DX spots from S50CLX Live DX Cluster in real time on your device showing all the current and recents Amateur Radio spots on all bands and modes.

Since 2012, the RTL-SDR is the simple and cheap way to give Software-Defined Radio a try. For about 25 euro you get a receiver covering much of the VHF and UHF range, and by either adding an upconverter, or using the direct sampling option, also the HF bands. They are so cheap because they are mass-produced as DVB-T receivers.

This page provides a fully customizable band plan. You can easily customize the frequency limits, scale, define custom windows for modes and activities, adding or removing bands. You can tehn Export to PDF or print the bandplan to distribute the document to help hams operating within the designated spectrum efficiently. Useful for both new and experienced hams looking to produce their custom bandplan.

The database of Chinese ham radios. We are here to show you that you do not need expensive kit from big brands to have fun with ham radio. With the explosion of open source designs, cheap manufacturing, and global delivery, you can now get on the bands and explore for less than ever before.

The Sputnik regenerative receiver is a compact and efficient project for amateur radio enthusiasts, tailored to the 40m band and adaptable for other HF bands. Designed for beginners, it supports AM, SSB, CW, and FM reception. The project emphasizes simplicity while delivering reliable performance, incorporating innovative features like diode tuning and a smooth regeneration control. Its small size, efficient power usage, and flexible design make it a popular choice for experimentation and learning in the homebrew radio community.

This page provides detailed information on various antenna designs specifically tailored for hams operating on the 80m and 160m bands. The article covers the pourpose and usefulness of each design, helping hams optimize their radio communication capabilities on these popular bands. Whether you are a beginner looking to improve your setup or an experienced operator seeking new ideas, this page offers valuable insights to enhance your ham radio experience on the 80m and 160m frequencies.

This project involves constructing a dual-band Moxon antenna, optimized for ham radio enthusiasts, with functionality on both the 10-meter and 6-meter bands. The antenna is designed to operate using a single 50-ohm feedpoint, acting as a mini-beam on 28 MHz (10 meters) and as a 2-element Yagi on 50 MHz (6 meters). Performance-wise, it offers a 4.0 dBd gain on 10 meters and 4.3 dBd on 6 meters, with impressive front-to-back ratios of 30 dB and 11 dB, respectively. Builders like Aleks (S54S) and Marcio (PY2OK) have successfully brought this design to life using the provided specifications. Aleks noted that bending the corners of the structure proved especially useful during assembly. The project comes with a detailed parts list, highlighting the use of aluminum tubes with different diameters and lengths to form essential components like the reflectors and radiators. For those looking to fine-tune the antenna, adjustments can be made by altering the length of certain parts that fit into larger tubes. The feeding system is equipped with a balun to accommodate different power levels, making the design versatile enough to handle outputs of either 300 watts or 1 kilowatt.

The T41-EP SDT is an open-source software defined transceiver designed by Albert F Peter (AC8GY) and Dr. Jack Purdum (W8TEE) with contributions from others. This detailed guide covers the design, theory, and assembly of the transceiver, making it suitable for both beginners and experts in SDR. Learn about Digital Signal Processing and how it is implemented in the T41-EP, as well as the modularity of its internal design. Kits are available for easy assembly, and a supportive community on SoftwareControlledHamRadio Groups.io provides additional resources for users. Note that software support for additional bands is in progress, offering potential future upgrades.

A 70cm / 432 MHz Transverter Project transverter circuit is an electronic device that converts a radio signal from the 2 meter to the 70 centimeter band and vice versa, allowing a single transmitter/receiver to be used for both bands. It consists of an IF stage, local oscillator, frequency multiplier, and amplifier. The circuit must be designed for minimal signal loss, noise and intermodulation distortion.

System Fusion is Yaesu’s implementation of Digital Amateur Radio, utilizing C4FM 4-level FSK Technology to transmit digital voice and data over the Amateur radio bands

The HB9CV antenna calculator aids amateur radio enthusiasts in designing antennas for VHF and UHF bands. By inputting the working frequency, users can obtain crucial dimensions like dipole lengths and distances. The tool, based on the HFSS antenna model, provides data on impedance, VSWR, and gain, optimizing front/back radiation ratios. It includes tips for fine-tuning using a Г-matching balun and compensating capacitor, ensuring effective performance and minimal VSWR for enhanced radio communications and direction finding.

Amateur radio enthusiast Jean-Paul Suijs discusses combating manmade noise (QRM) in radio signals using AI. Detailing experiments with phase-shifting techniques and the self-learning nature of AI, he explores AI-based audio processing apps for real-time noise cancellation during radio contests, demonstrating results on both medium wave and shortwave bands.

Experimenting and testing vertical antenna for HF bands on mobile operations.

The J-pole antenna calculator helps users design custom J-pole antennas for specific frequency bands. It provides dimensions for key antenna sections based on the chosen frequency and material’s velocity factor. The calculator also offers insights into J-pole antenna mechanics, velocity factors, and mounting tips, making it ideal for enthusiasts creating antennas for amateur or mobile radio communications.