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Microwaves101 provides an extensive repository of information covering fundamental principles of microwave design, targeting engineers and radio amateurs interested in the higher frequency spectrum. The site features a detailed _encyclopedia_ of microwave terms and concepts, alongside practical design considerations for various components and systems. It serves as a foundational reference for understanding RF propagation, transmission lines, and active/passive microwave circuits. The resource includes numerous calculators for impedance matching, filter design, and other critical RF parameters, facilitating hands-on project development. Discussions on **10 GHz** equipment and **24 GHz** projects highlight practical amateur radio applications, extending to operations up to 134 GHz. Content spans from basic theory to advanced topics like MMIC design and antenna characteristics, supporting both educational and practical endeavors in microwave technology.

This page details my building of a 100 Watt Power Amplifier for the 432 MHz Band based on two Motorola MRF646 transistors taking inspiration by Carlo Gnaccarini VK3PY, formerly VK3BRZ

An home made VNA made with Arduino Nano. This project features an LCD display 4x20 works from 1 MHz to 60MHz, can use bluetooth connection with Blue VNA android app.

The goal of this interesting project is to monitor a particular set of frequencies for a set period of time. In this article your will find instructions to build and operate an all-band WSPR node using cheap hardware and free software. At the end of this you'll have a Raspberry Pi, connected to an RTL-SDR dongle that monitors all of the WSPR frequencies rotating randomly every 15 minutes.

Mint tin transformed into a switched 9v battery to Anderson PowerPole

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

An optocoupled audio interface between PC and Transceiver for digital modes. The article includes full schematic of complete board and build instructions.

UHSDR stands for UniversalHamSoftwareDefinedRadio. The project provides the firmware to run standalone HAM transceivers. It currently supports STM32F4 and STM32F7 MCU based QSD designs.

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.

This article provides a step-by-step guide for assembling a Raspberry Pi-based Satellite Tracker Interface, designed to work with Green Heron Engineering's RT-21 controllers and MacDoppler software. The guide covers hardware assembly, SD card image installation, and system configuration for satellite tracking.

The MiniTioune receiver project, developed by Jean-Pierre F6DZP, consists of the home constructed MiniTiouner hardware which interfaces via a standard USB 2.0 port to a Windows PC running the MiniTioune software. It can be used to receive satellite broadcasts transmissions making it ideal for use on Q-oscar 100 Es hail-2 without any external frequency converters.

Analysis, design and construction of a simple & useful SWR meter from yesteryear! Schematic diagram, pictures and instructions to build a Monimatch style SWR Meter

The amateur radio listener for when you're not on the radio. Repeater-START, the offline repeater listing app for Windows, Linux, Raspberry Pi, Ubuntu, Librem Phone is available, Now with grid square display, topographical maps and frequency preferences

A multi-plaform CW-Trainer program (already tested on Windows and Linux Ubuntu, now testing on Raspberry Pi), multi-skin and it will provide different learning programs.

Explore the detailed setup, essential software, and operational nuances for Greencube (IO-117), a Medium Earth Orbit (MEO) satellite with a 70cm digipeater, offering DX possibilities for amateur radio enthusiasts. From antenna configurations to software choices, this guide covers everything for a successful Greencube experience.

Experimentin wire antennas on top band using several type of aerials. This includes a 40 to 160 meters EndFed Half Wave kite antennas and 160m/80m loaded vertical antenna.

This stacking offers a well known simple phasing technique. All elements can be fed in parallel by open wires provided that they are fed in phase. This can be achieved by twisting the open wire phasing-lines at 180 degrees.

In this article we share a useful and simple project to convert an unneeded car power cable to an Anderson PowerPole adapter.

A simple and cheap solution to monitor temperature of your repeater implementing a Raspberry Pi device with a set of popular tools made in python a database and RRD tool

A polarity checker is a very useful item to have around the shack and in a go-kit. This project, inspired by a QST article on powerpole connector protection illustrate how to build a polarity checker.

Mounting on roof at the right ground level can greately impact on antenna performances because will affect the radiated angle of energy.

This article discusses suitable first HF antenna options for amateur radio operators with limited space. It recommends an Off-Center Fed (OCF) Dipole and a Vertical Dipole, detailing the installation processes, considerations for stealth and ease of setup, and the characteristics that make them ideal for newcomers. Safety warnings and maintenance tips are provided to ensure effective and secure operation.

The MiniPA Linear Amplifier for HF page discusses the popularity of QRP for HF among ham radio operators, such as those using the Yaesu FT818 or low power SDR transceivers. It explores the use of cheap kits from eBay or Chinese suppliers to build a 70-100W SSB amplifier using IRF530 MOSFET transistors. The article provides a review of the MiniPA design, including its features, components, and assembly process. It also highlights the importance of using a heatsink and forced air cooling for optimal performance. This page is useful for hams looking to enhance their HF rig with a budget-friendly amplifier.

The author has build the Hermes-Lite SDR v1 and v2 versions describing with a very accurated text and picture the process. Additionally has documented measurements for each component

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

A portable loop antenna, made with a 3 meter loop resonates with the chosen capacitor from just below 7MHz to about 28.300MHz which makes it usable on the bands from 40m to 10m.

Remotely monitor the output power and SWR of your station via a web browser. WT32/ESP32 based project, combined with a directional coupler setup. It reads two voltages which are supplied by the directional couplers. From these, the respective power is calculated with the help of a calibration data table to be created by the user.

Paul McMahon presents a compact VSWR meter designed for QRP portable use, ideal for SOTA operations with rigs like the FT817. The device, constructed from readily available components, employs a simple resistive bridge for wideband performance from 1.8MHz to 52MHz, with diminishing accuracy at higher frequencies. Key features include no need for external power, simple calibration, and operation with low power levels. The design, detailed with parts lists, schematics, and construction guidelines, ensures a 2:1 worst-case VSWR to protect transceivers during antenna matching. Calibration points are set for accurate VSWR readings at various loads.

NPR (New Packet Radio) is a custom amateur radio digital protocol, designed by F4HDK to transport bidirectional IP trafic over radio links on the 70cm band. This IP protocol is optimized for point-to-multipoint topology, with the help of managed-TDMA. Bitrate is up to 500kbps. Home Made modem has a built-in ethernet port to connect to PC. To boost power a DMR amplifier is required to reach 20W. This project is an extension of HSMM - Hamnet - AREDN networks

How to easily receive and decode CubeSat telemetry

This blog chronicles the development of an 80-meter vertical antenna for amateur radio operation. The author constructs a top-loaded vertical using fiberglass poles, achieving significant performance improvements over their previous end-fed wire antenna. Comparative testing using the Reverse Beacon Network and on-air contacts demonstrates 8-10 dB gain on the east coast. The project evolved to include 40-meter capability through a modified design featuring a four-wire vertical cage, loading coil, and strategic guying system. Despite challenges with signal wobble during windy conditions, the vertical consistently outperforms the end-fed wire, particularly for reaching distant stations during nighttime propagation.

A Home made antenna tuner for QRP transceivers. This small tuner is the ideal for portable operations with random length wires or whenever you have not a resonant antenna.

A useful and simple project to convert an unneeded car power cable to an Anderson PowerPole adapter.

his article explores the construction of a PL519 tube amplifier, utilizing Ulrich L. Rohde N1UL's insights. Focusing on a modest 25W continuous output, the design ensures robustness with forced air cooling. The detailed breakdown covers input matching, screen grid voltage generation, bias adjustment, anode power supply, heater power supply, and monitoring circuitry, providing valuable guidance for ham radio enthusiasts.

Arduino Digital Transceiver (ADX) is a low-cost HF transceiver for digital modes. This Arduino-based project, inspired by QDX, features four bands, including 80m and 20m, supporting FT8, FT4, JS8call, and WSPR. Designed for simplicity and affordability, it uses an Arduino Nano, SI5351 module, and CD2003GP receiver. The ADX project emphasizes easy procurement, construction, setup, and operation, making it an accessible option for QRP enthusiasts. The firmware update enhances functionality, including CAT control support.

A simple DIY project for a remote cw key connected to your Flex Rig (actually it can be any other rig). On the remote side it uses and Arduino Uno board and a cheap HanRun Enc28J60 ethernet shield. On the local side it uses a key (better a keyer) connected to a serial port of your pc

The TangerineSDR is a Modular Software Defined Radio Project with the following objectives, Development of SDR radios that allow experimentation, provide support to unaffiliated other groups, to provide hardware modularity, to allow varying performance, To allow users to experiment with differing configurations.

The document details the construction and performance of a rotatable flag antenna designed for a small lot. The 7x14 feet flag, built with fiberglass poles and an aluminum hub, shows improved reception compared to the author's previous transmit antenna. Key components include a conventional transformer for impedance matching and a variable resistance termination system to optimize performance. Despite challenges like nearby objects affecting signal patterns, the antenna consistently provides better signal-to-noise ratios, making it a valuable addition for low-band listening in suburban areas.

PCB is an interactive printed circuit board editor for Unix, Linux, Windows, and Mac systems. This Software runs across multiple platforms such as Unix, Linux, Windows as well as Mac systems. This Tool is widely used for electronics as well as electrical circuit designing that comes with schematic capture. PCB offers high end features such as an autorouter and trace optimizer which can tremendously reduce layout time.

Arduino Flex Controller can be used with the new Flex 6000 Signature rigs. It is a DIY project and in these pages you will find all the informations you need to build and program your own. It is a perfect companion when used next to the official SmartSDR program but it can be used in stand-alone mode, without a PC.

Here are some hints and tips for construction of a good preamp for satellite work.

In this post, we describe how to make a pigtail cable to connect the Kenwood TH-F6A triband HT to a 12Vdc power source via an Anderson PowerPole connector.

This is a power amplifier project for a RF 600W 1.8 MHz to 70 MHz linear amplifier including a Low Pass Filter. Projects includes schematics, pictures, PCD design, fans details, note on PA ferrite chokes and assembling instructions

Removing disturbing RFI from the Behringer HA400 Headphone Amplifier, using ferrites and capacitors soldered in the main circuit board of the small amplifier.

The article details the C-Pole antenna project, emphasizing its portability and ease of setup for amateur radio operators. Key features include its compact design as a vertical half-wave dipole that requires no radials, making it functional at various locations. The antenna employs capacitive loading to reduce physical length while maintaining efficiency. It includes practical advice on resonance tuning, impedance matching, and construction materials, along with a calculator for determining dimensions based on desired frequencies. Overall, it presents a user-friendly solution for portable ham radio communication.

Wait to decode callsigns, then call them using UDP protocol. This utility auto respond to wanted call-signs it is a neat alternative for JTAlert. Automatic logging. Available for both MacOS and Windows (10+). Make sure to automatically call any Wanted callsigns specified. Can also be used to monitor band opening. Can handle callsign exclusions, can even handle wanted callsigns according to your worked before Rules. Works either with JTDX or WSJT.

This HF active antenna is a build of the PA0RDT Mini-Whip from a kit, it covers the entire HF band (3 to 30 MHz) and below (supposedly down to 10 kHz). It is powered by an external 12-15V supply, consuming about 50 mA.

Ulrich L. Rohde N1UL conceived an outstanding 2m to HF receiving converter with specific requirements, including 144-148MHz to 28-32MHz coverage, low noise, high IP3, and a unique modular design. The design decisions emphasize modularity, absence of preselection, stability, and a passive mixer, showcasing Rohde's distinctive approach.

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.

Program for do application and endorsement for all ARRL awards-30 awards-18 for DXCC -12 for others and 8 special querry (how long I'm waiting for QSL. You can merge several awards and endorsement in a one application and upload adif file to ARRL page by ON-LINE method. Offering optimization task for cost checking QSO.Cooperating CLUBLOG