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A PIC16F876 based, automatic 1.8 to 60 MHz Digital SWR/WATTmeter capable of displaying both the SWR and P.E.P.power values, with a bar graph on the second line tracking the instantaneous power.

SWR and RF power meter for home usage, 8 different RF probes with different characteristics and power ranges by OK1DX

A Portable Low Frequency Antenna Analyzer, For those of us who like to play with antennas on the ham bands, one of the handiest tools to have around the shack is an "antenna analyzer". These gadgets combine a signal generator and standing-wave ratio (SWR) sensor in a small battery-powered unit.

Contruction manual to build a 4:1 balun, it has good performance from 160 through 10 meters.

Converting Computer Power Supplies (PSU) to stabilized 13.8 V DC 20 A

This little gadget is that it allows you to tune up at full peak output power, whilst limiting the average power to a fraction of the peak, thereby protecting the PA from meltdown

This high antenna require a large ground composed by 40 radials. It's not very handy expecially in windy situations but is very powerfull in pile-ups. In italian

Over 75 years of engineering expertise underpins Bird Electronic's offerings in RF power measurement, critical for maintaining peak performance in amateur radio stations and professional communication systems. The company specializes in a range of test equipment, including wattmeters, SWR meters, and antenna analyzers, essential for optimizing antenna systems and ensuring efficient power transfer. Their product line extends to various RF components such as filters, cables, and connectors, all designed to meet stringent technical specifications for reliability and accuracy across diverse frequency bands. Bird Electronic's instruments, like the _Bird 43_ Thruline Wattmeter, are widely recognized for their robust construction and precise measurement capabilities, providing hams with confidence in their station's operational parameters. These tools enable accurate assessment of forward and reflected power, SWR, and modulation characteristics, which are vital for troubleshooting and maximizing radiated power. The company's commitment to innovation ensures that its products remain relevant for modern RF challenges, from HF through microwave applications, supporting both traditional analog and advanced digital modes.

PC power supply conversion for ham radio use. Slide show overview showing how convert PC Power supplies to ham radio use presented at the August 2007 FSARC meeting.

Gi7b is tube designed for microwaves but working good as HF amplifier. Idea is to build cheap, reliable HF amplifier covering 160 meters band.

When one operates at low power on SSB, speech processing becomes almost essential to get through the QRM. The circuit is a low cost speech processor that will perform well with a minimum of construction effort.

Details a practical QRP wattmeter construction, leveraging a simplified SWR meter design by JA6HIC. The project focuses on a forward-only power measurement circuit, providing a functional instrument for RF power levels from milliwatts up to 5 watts. It maintains a 50-ohm input and output impedance, suitable for typical QRP transceivers and antenna systems. The resource includes the schematic for the "VSW" (Very Simple Wattmeter) and outlines a six-step alignment procedure. This calibration process involves using a known RF source up to 5W, setting full-scale deflection, and marking power increments. It also addresses minimizing frequency effects on readings with a 100pF trimmer capacitor, noting that measurement error is highest at the lower end of the scale. Construction notes mention using a piece of RG-213 coaxial cable for the inductance and coupler, with the wattmeter assembled in early 2003. The author provides an example measurement showing 0.8W into a dummy load and 1W into a 3-element beam.

Inline RF Power & VSWR Meter. A DIY meter 0 to 30 Watt with Average and Peak. Circuit Description, Arduino Nano software code and part list to DIY your own Digital SWR Meter

The "Tenna Dipper" is a low power antenna analyzer and ATU tuning aid. With this handy accessory, you can determine the 50 Ohm resonance frequency of antennas or you can adjust your antenna tuner for a 50 Ohm match without generating QRM

PA3FWM's software defined radio (SDR) page documents his extensive hardware and software development efforts between 2004 and 2009. Initial experiments utilized a direct conversion receiver with 90-degree phase difference, feeding a PC soundcard at 48 kHz sample rate, covering 24 kHz of spectrum around a 7080.5 kHz local oscillator. This setup, similar to AC50G's QEX 2002 article, allowed for basic I/Q signal processing to distinguish signals above and below the LO frequency. Limitations included fixed crystal frequencies, 16-bit dynamic range, and narrow bandwidth. Subsequent hardware iterations aimed for enhanced performance, incorporating external 24-bit ADCs with 192 kHz sample rates, connected via 10 Mbit/s Ethernet. A **MC145170-based PLL** and programmable octave divider provided a 58 kHz to 30 MHz tuning range. The **Tayloe mixer** was employed, with differential outputs feeding a PCM1804 ADC. An ATmega32 microcontroller handled serial data conversion to Ethernet frames, though without CRC calculation due to processing constraints. Later designs integrated AD7760 2.5 Msamples/second ADCs and a Xilinx Spartan-3 FPGA, enabling direct reception of 0-1 MHz spectrum and eventually 2.5 MHz bandwidth across the shortwave spectrum. Software was refactored to use an initial 8192 non-windowed FFT for efficient high-bandwidth processing. The project culminated in a two-way QSO on 21 MHz using the developed hardware and software, demonstrating transmit capabilities with a D/A converter. The system exhibited a 2.5 MHz wide spectrum display and a zoomed 19 kHz display, capturing signals like ionospheric chirp sounders and RTTY contest activity. Challenges included noise leakage from digital circuitry and cooling for high-power dissipation components.

Build a Low Power 4:1 Balun , by Charles Greene, W1CG with full-color, full-resolution graphics from the pages of QRP Homebrewer

Well documented Amateur Radio HF/VHF antenna projects, high power Russian GS35B RF amplifiers, mobile RFI solutions, related accessories, vintage radios, Six meter equipment, and useful techniques by K8CU are inside.

An easy to make HF low pass filter form high power

Free Russian hamradio server special for radiofanats from CIS. Search engine on callsigns, electronic circuits and hamradio programs in www powered with knowledge base.

80m hexfet power amplifier by W7ZOI

The best way to describe a go-box is a complete amateur radio station in a box. An example is described in this article. The project describes building a portable amateur (ham) radio station, known as a "go-box," housed in a durable orange Pelican case. The go-box contains all necessary radio equipment except for external power and antennae, which are carried separately. It includes items like a Yaesu transceiver, power supply, antenna tuner, speaker, and a clock. The case is designed for mobility and visibility, with a vertical layout to allow in-vehicle operation. Future upgrades might include cooling fans, an LED lamp, and built-in antennae for better functionality in various conditions.

Amateur radio accessories, power supplies, tvi filters, speakers, microphones, swr meters, preamplifiers, switches, cable and connectors,

Rolling your own transformers and chokes. Rewinding salvaged power transformers, considerations and step-by-step guide

VHF power amplifiers made in germany

The Powerpoint presentation below was given by Fred Hopengarten, K1VR, at the 1998 Dayton Hamvention Antenna Forum

The K8ZT website provides a curated collection of amateur radio resources, encompassing software tools, informational articles, and external links relevant to various aspects of the hobby. It features utilities for _log analysis_, insights into QRP operations, and guidance on obtaining vanity callsigns. The site also includes sections dedicated to shack design principles and general ham radio information, reflecting a broad interest in practical station setup and operational enhancements. Specific software offerings are presented alongside discussions on their application, such as tools for analyzing contest logs to identify operational efficiencies or areas for improvement. The content often integrates personal experience with technical explanations, providing a practical perspective on topics like antenna selection for low-power operations or optimizing station workflow. The resource distinguishes itself by combining software recommendations with contextual information, aiding operators in making informed decisions about their station's technical and operational aspects.

The Emtech ZM-2 Antenna Tuner is a nifty little portable transmatch for QRP (low power). It utilizes the well-known Z-match circuit, which is especially useful for balanced antennas (like dipoles and loops).

The Radio Component Database offers a structured collection of technical documentation for various radio components, primarily focusing on those relevant to CB-Radio and general transmitter/receiver equipment. It categorizes components such as RF Bipolar Small Signal Transistors, RF FET Small Signal Transistors, RF Power Transistors, and Integrated Circuits, providing specific data for each type. The resource includes a "Shortform Transistor Catalogue" and a section dedicated to Variable Capacitance Diodes, detailing their characteristics and applications. A significant feature is the inclusion of cross-reference databases from major manufacturers like NTE Electronics Inc., ECG, Fujitsu, Motorola RF-Components, and Philips Components, which can be invaluable for component substitution or identification. Users can access specific technical data from manufacturers such as National Semiconductor, NEC Semiconductor, and Toshiba Components, with some data available in _PDF_ format. The database serves as a reference for hams and technicians working with RF circuitry, offering a centralized location for component specifications and alternatives, which can save considerable time during design or repair work.

Pictures and circuit diagramm to build this power amplifier for 2 meters

An RF power amplifier, providing 7 Watts output in HF bands, schematic by ON6MU

13.8 V / 15 A from a PC Power Supply in German

The article "Exploring the World of 10 Meter Beacons" by Ken Reitz, KS4ZR, provides an in-depth look at 10-meter beacon operations, focusing on their utility for propagation analysis. It details FCC Rules part 97.203 governing beacon stations, including license requirements, power limits (under 100 watts), and the specified band segment of 28.200-28.300 MHz for U.S. operations. The content highlights the diversity in beacon construction, from converted CB radios to home-brew QRP transmitters, and discusses the robust operating conditions these 24/7 stations endure. The resource presents several case studies of active 10-meter beacon operators like Ron Anderson KA0PSE/B, Domenic Bianco KC9GNK/B, and Bill Hays WJ5O/B, detailing their equipment, antenna setups, and typical signal report volumes. It also introduces the NCDXF/IARU International Beacon Project, which features 18 synchronized beacons worldwide transmitting on 28.200 MHz at varying power levels (100W, 10W, 1W, 100mW) to facilitate propagation testing. The article also covers the PropNet Project utilizing PSK31 on 28.131 MHz and the 250 Synchronized Propagation Beacon Project on 28.250 MHz. Practical advice for monitoring includes using the RST reporting method, understanding the impact of the solar cycle on 10-meter propagation, and tips for setting up a personal beacon, such as frequency selection and power output considerations. The IY4M Guglielmo Marconi Memorial Beacon Robot on 28.195 MHz is also mentioned for its automatic QSO mode. The article concludes with a list of other resources for 10-meter beacon information.

Daiwa Industry, maker of power suppliers, coax cable and antenna switches, power meters, SWR meters, DC-DC converters

Article about omega and gamma matching, related to bandwidth, loss and component failures, heating and power ratings

Splitting an antenna between two receivers or in use as the phasing harness in stacked antennas where there is a need to equally split the power from the transmitter between two antennas

It consists of a group of JavaScript driven web pages that are intended for use as a quick reference for Ham Radio operators or just anyone interested in electronics. Offer calculators for Resistors, capacitors, inductors, power supplies, filters, attenuators and antennas

Amateur Radio Ham Radio Maidenhead Grid Square Locator Map online. This map allow just a point and click to determine dynamically the correct six characters locator. Other functions allow to calculate the distances among two given locators, or coordinates. Hover over map, specify grid, or enter latitude and longitude to show grid and/or calculate distance. Map is powered by Bing Maps.

SDR-RADIO.com is a Windows console for SDR receivers and transceivers. Designed for the commercial, amateur radio and short-wave listener communities, the console provides a powerful interface for all SDR users. Many SDR owners have made their radios available over the internet. Just look at the Web Servers page for a list of the radios you can use. You do not need a licence to use this sodftware with RFSPACE, FUNcube Dongles, Soundcard (SoftRock) and low-end SDRs.

20/22 Ampere or 30/32 Ampere 13.8 volts power supply RE-PSF14A20 or PSF14A30 by ON6MU

144 and 432 Mhz GS35b High Power Amplifier

Managing extensive amateur radio contact logs efficiently requires specialized software that integrates various operational aspects. Aether provides a macOS-native logging solution, designed from the ground up using Apple's Cocoa, to streamline QSO entry, organization, and retrieval for Mac users. It supports modern macOS technologies and offers an intuitive interface, aligning with the user experience expected on Apple platforms. The application includes features such as automatic dupe checking, which quickly identifies previous contacts with a station, and awards tracking, indicating if a new contact is needed for specific operating awards. Aether also integrates rig control via RS-232, automatically populating frequency, mode, and power data from supported Elecraft, Icom, Kenwood, Yaesu, and some TEN-TEC transceivers. This automation reduces manual entry errors and speeds up the logging process. Furthermore, Aether offers comprehensive QSL management, including synchronization with eQSL.cc and Logbook of The World, and the ability to print QSO detail and address labels for paper QSLs. It also incorporates automatic callbook lookup from sources like QRZ.com and HamQTH.com, and calculates distance and beam heading, with Google Maps integration for visualizing contact locations. Full ADIF and Cabrillo import/export capabilities ensure compatibility with other logging software and contest submission platforms.

How to homebrew an hex beam antenna for 20 17 15 12 10 meters band by VA7ST

We offer a large selection of standard and custom High Power RF and Microwave amplifiers for broadband, general communication, matched band, and personal communication markets.

VU2RAR basic VHF power amplifier suitable for 144-146 Mhz output power can vary from 3 to 25 Watts.

HF power amplifier project by YB0AH

SDR Receiver a compact high performance HF software defined radio receiver designed to be used in fixed or portable stations. Version 2 of the receiver is now available. It now has an RF pre-amplifier using a power MOSFET and other revisions to improve it's performance both as a stand alone receiver and as an IF panadaptor with HF and VHF transceivers.

The Discovery series of amplifiers are designed and built in the UK by Linear Amp UK Ltd, one of the world's leading amplifier manufacturers, specializing in high power RF tube amplifiers. The amplifiers use large GS31 or GS35 ceramic triode tubes. Band coverage 6m, 2m and 70 cms

The RigPix database entry provides a comprehensive technical overview of the Icom IC-746 amateur HF/VHF transceiver, detailing its operational parameters and physical characteristics. It specifies the transmit frequency ranges across 10-160 meters plus WARC bands, 50-54 MHz, and 144-146/148 MHz, alongside receive coverage from 0.03-60 MHz and 108-174 MHz. The resource outlines supported modes including AM, FM, SSB, CW, and RTTY, noting a tuning step resolution down to 1 Hz and a frequency stability of ±5 ppm. Key electrical specifications are presented, such as a 13.8 VDC power supply requirement, current drain figures for RX (1.8-2 A) and TX (Max 20 A), and RF output power ranging from 5-40 W for AM and 5-100 W for FM, SSB (PEP), and CW. The entry details the triple conversion superheterodyne receiver system, listing IF frequencies at 69.01 MHz, 9.01 MHz, and 455 KHz, along with sensitivity ratings for various modes and bands. Transmitter section specifics include modulation systems and spurious emission levels. Additional features like a built-in auto ATU, electronic keyer, simple spectrum scope, DSP, and CI-V computer control are noted. The page also lists related documents, modifications, and an extensive array of optional accessories, including various filters, microphones, and external tuners, providing a complete profile of the IC-746.

ERP Calculator is an Amateur Radio software utility designed to perform a side-by-side comparison of two Ham Radio antenna systems. ERP Calculator comes pre-programmed with data files including published data for several popular brands and types of coax cable as well as several popular antenna system brands and models. ERP Calculator displays values of ERP, Antenna Power Gain, Antenna Feed point Power, Antenna System Gain in dB, Antenna Gain in dBd, SWR Attenuation in dB, SWR Power Attenuation, Coax Loss in dB, and Coax Power Loss

High-power 3-500 HF linear amplifier by Don Pinnock G3HVA