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Circuit designs for IC audio amplifiers by N1HFX

A fully documented restoration project of a Hallicrafters SX99 receiver

The purpose of this article is to provide radio amateurs with enough background information to understand the technical challenges involved in small-station digital EME on the 144 and 432 MHz bands.

Bearing Info uses an extract from the VKLogger.com web site Op-Info to make it easy to find a callsign and hence bearing and distance information. It is written specifically for VK operators for use in Field Days although it could be considered a general purpose amateur radio utility, mainly for Aussies by VK4ADC

A DIY aluminium push up mast project. The final mast includes 7 aluminium tubes with 6 cable clamps

Tutorial about writing a software SSTV modulator/demodulator using slant correction and several improvements. It requires programming language knowledge and programming skills.

The Shoddytenna is a 160 meters band vertical antenna intended for portable use. This antenna takes just 15 minutes to erect on site, can be carried by hand and is ideal for local groundwave work.

A multi band antenna for HF band capable to operate from 10 to 80 meters band depending on wire lenght loaded with a small inductance neat the feed end.

Use your Smartphone as an Oscilloscope to visialize signals from 150 Hz to 15kHz and as a Signal Generator to generate sinusoidal, square and triangular signals up to 15kHz

DTMF Keypad for radios without one. A project with picture and schematic diagrams to homemade a DTMF keppad

How to make a Morse Code Oscillator

Constructing a basic multimeter involves integrating a 0-1mA meter movement with various shunts and multipliers, selected via a switch, to create a versatile instrument capable of measuring DC volts, current, and resistance. The design outlines two main units: a primary unit handling six DC current ranges up to 1 amp and eight DC voltage ranges up to 1000 volts, alongside an internal battery for an ohms range up to 200,000 ohms. This approach allows for a practical, hands-on understanding of meter operation. An add-on unit further extends the multimeter's capabilities, incorporating a meter rectifier and switched series resistors to provide four AC voltage ranges up to 100 volts. Additional shunt and series resistors, designated Ra and Rb, are included to expand the instrument's range to 10A and 5kV, demonstrating how modular design can enhance functionality. When this add-on is in use, the main instrument is set to measure 1mA FSD, connecting via specific lugs. Component selection emphasizes precision, with 1% tolerance high stability resistors for series elements and Eureka resistance wire for shunts. The design specifies values calculated for a meter with 60 ohms internal resistance, noting that these would require modification for different meter characteristics. Experimental adjustment of shunt values is recommended to ensure accurate readings against a calibrated reference meter, reinforcing practical calibration techniques.

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

A 3.2m EME dish project that provides a better performance on 1296 MHz (10+dB sun noise vs. 6dB with my 432 array) and an even better performance on 2304 MHz

This project takes after the VGA-to-Scope converter by using composite video rather than VGA signals to create a display on an oscilloscope.

PropNET is an ad-hoc 2-way (and potentially, "more-way") RF-based digital communication network whose activity is reported on the Internet. As participating stations periodically ID and exchange data, they report their activity to an Internet data-collection hub for presentation through this web site.

An universal antenna tuner interface, the Kenwood Remote LDG Tuner Interface by af6sa

It is possible to add a very small Bluetooth transmitter to the 3.5mm headphone jack and then use a pair of Bluetooth headphones around the shack. In this article Author provides some tips on choosing the proper Bluetooth interface.

Build a digital AC voltmeter to measure the output range from 0 to 150VAC with reasonable accuracy

A 3CX1500/A7 8877 144mhz W6PO amplifier, that running a little over 4kv on the plate, this Amp will do over 2kw out.

Homemade an external T/R switch for your vintage RTX by KB8OJH

HM-36 Modification to make it work with an IC-7200 and the IC-7600

Schematic diagram of a two tone audio oscillator by VK3YE

Building the Three-Element Hex Beam. A project and construction phase of an HF hex-Beam antenna using trees to hang the antenna and a Channel Master antenna rotator.

This DIY vertical multi-band Windom antenna offers a practical and effective solution for amateur radio enthusiasts seeking a versatile and compact antenna for HF communications. Its simplicity of construction, multi-band capability, and favorable performance make it a valuable addition to any radio shack. The article provides detailed instructions on constructing the antenna and balun, along with diagrams and component specifications. Field tests demonstrated successful contacts with stations across Europe and North America on 14, 18, and 28 MHz. The antenna exhibited comparable performance to a W3DZZ dipole and outperformed a Cobweb antenna on 18 MHz. Low noise levels were observed, effectively suppressing background noise.

This antenna is an off-center fed spiral dipole for 40 meters. The spiral dipole is very compact, making it well-suited for limited space (like an apartment patio), while the off-center feed gives the antenna some multiband capability.

While transistors have many uses, one of the less known uses by amateurs is the ability for bipolar transistors to turn things on and off

An experimento of a 40 meter delta loop antenna both in horizontal and vertical polarization and several elevation angles with interesting notes about the effect of the radial field under the antenna.

A homebrew project about a bluetooth interface to connect a transceiver to an audio headset.

Converting a computer\'s VGA output for an oscilloscope

A page with pictures of the Ameritron AL-80B Amplifier, including the inside box where is possible to see the 3-500ZG tube capable to provide 800W in CW.

A discharge circuit which you could use to cycle the batteries

Fox Controller, designed by VE2JX and VE2EMM includes schematic diagram to build the transmitter.

A new ham radio shack desk made of a solid core oak door.

Mirage BD-35 2M/70CM RF amp high SWR, how to troubleshoot

A Fox transmitter by VE2EMM with construction details part list and schematic diagram

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)

Launch of a hybrid rocket from high altitude by untsville Alabama L5 Society

A WSPR beacon project based on Arduino nano (atmega328P) based microcontroller

Network Analyzer on an Arduino Shield which covers from 0-72MHz using an Analog Devices AD9851 DDS chip

Operating in the Caribbean, the Jamaica Amateur Radio Association (JARA) provides a central hub for amateur radio enthusiasts on the island. The association details its **repeater network**, including IRLP node 7673 and ECHOLINK access, alongside information on band activity and packet radio operations. Members can access specific documents like the JARA Membership Form and the JARA Disaster Plan, while general visitors can review the full JARA Regulations and learn about the club's history. The site features a photo album and outlines various radio activities, including what constitutes a JARA Field Day. It also provides essential resources such as the Reciprocal License Form and Jamaica Amateur Radio Regulations, crucial for visiting operators. The **WINLINK Project** and Radio Voice Procedure are also covered, offering practical guidance for communications. JARA maintains affiliations with international bodies like **IARU Region II**, ARRL, and RSGB, and lists important organizations such as SATERN 14.265, Jamaica Red Cross, and the National Hurricane Center. The website also includes links to other amateur radio clubs across North America, the Caribbean, and Central and South America, fostering regional and international connections.

The online Morse code translator and decoder provides functionality for converting plain text into Morse code and decoding Morse code back into text. Users can input text directly into a designated box for translation to Morse, with the tool ignoring characters that lack a Morse equivalent. Conversely, Morse code can be entered using periods for dots and minus signs for dashes, requiring a single space to separate letters and a forward slash to delineate words. The interface also supports direct Morse input via a button, where a half-second pause separates letters and a 1.5-second pause separates words. The resource details the historical context of Morse code, noting its invention by _Samuel F.B. Morse_ in the 1830s for telegraphy, and its continued use by amateur radio operators for recreational purposes and emergency signaling, such as the **SOS distress signal**. Guidance on learning Morse code suggests using online translators for practice and listening to amateur radio transmissions. The tool offers an audio playback feature for translated Morse, allowing users to hear the code at various words per minute (WPM) settings. It also includes a visual chart to aid in memorizing the dot and dash sequences for the alphabet.

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.

An end-fed half wave antenna matching unit made of 3:24 turns ratio on a FT140-43 toroid with a 150pF capacitor across the input.

A project to turn a Raspberry Pi into a very versatile tracker, digipeater and an iGate

The home page of WSJT-X Improved, an enhanced version of WSJT-X, the popular tool for hams interested in digital modes such as FT8 and JT65. The software provides enhancements and improvements to the original WSJT-X program, making it easier and more efficient for ham operators to communicate digitally. Whether you are a beginner or an experienced operator, this download can help enhance your digital communications capabilities. Free downlaod and full description of improved features.

Presents various amateur radio topics through blog posts, detailing operational experiences and technical insights from the perspective of SV2YC. The content frequently discusses antenna projects, such as a **portable 20m/40m dipole** designed for rapid deployment, and explores the performance characteristics of different wire configurations in varied field conditions. Observations on propagation and band activity across the HF spectrum are also regularly documented, providing practical context for fellow operators. Specific entries often include detailed accounts of **DX contacts** and participation in minor contests, outlining station setup, power levels, and antenna choices. The blog also covers modifications to commercial transceivers and homebrew accessory construction, offering practical advice on improving station efficiency and functionality. Further posts delve into software applications for logging and digital modes, sharing configurations and operational tips for maximizing their utility in daily amateur radio activities.

Wireless Society of Southern Maine Projects, instructions and photos for many ham radio projects and experiments, including antenna construction and modelling, kit building, station setup, restoration and more

Ham radio, amateur radio, satellite communication, radio, radios,antenna, antenna design, yagi, cross yagi, power divider, splitter, Brisbane.