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Over 30 distinct shortwave (SW) receiver models are reviewed, offering insights into their performance, features, and user experiences. These evaluations, contributed by readers of the Usenet newsgroup **Rec.radio.shortwave**, cover a wide array of portable and tabletop radios, including popular units like the Grundig YB-400, Sony ICF-SW77, and various Realistic DX series models. Each review details aspects such as frequency range, tuning steps, SSB functionality, antenna performance, and construction quality, often comparing them to other receivers or ham transceivers like the Icom 725. For instance, the Grundig YB-400 review highlights its 144-30000 kHz AM/SSB coverage, direct keypad entry, and 40 station memories, noting its useful narrow bandwidth and tone switch for adjacent signal separation. It also discusses the **SSB mode** stability and the limitations of its 1 kHz frequency resolution for precise zero-beating. The review further details antenna performance, including the effectiveness of the built-in whip, the provided 7m reel antenna, and the potential for overload with larger outdoor antennas. Other reviews delve into specific issues, such as the Sony ICF-SW77's frequency display inaccuracies and timer malfunctions, or the Realistic DX-342's compact size and surprisingly good MW DXing capabilities despite its analog tuning. The collection provides practical, user-generated feedback on sensitivity, selectivity, audio quality, and ergonomic features, helping shortwave listeners understand the real-world performance and quirks of these receivers.

Homebrew project of a vector network analyser VNA by N2PK

This resource presents a technical guide detailing antenna measurement theory, focusing on the fundamental electromagnetic principles governing antenna operation and characterization. It delineates the three primary spatial regions surrounding an antenna: the reactive field (0 < r < lambda/2pi), the radiating near-field (lambda/2pi < r < 2D2/lambda), and the radiating far-field (r > **2D2/lambda**). The guide defines key antenna parameters, including polarization, input impedance, VSWR, directivity, gain, efficiency, Effective Isotropically Radiated Power (EIRP), antenna noise temperature, and the G/T parameter. Radiation patterns are discussed, with examples of both rectangular and polar forms, emphasizing the determination of patterns in the far-field region for constant radial distance and frequency, typically characterized by a main beam with **3 dB** beamwidth and sidelobes. The document further elaborates on the mathematical definitions of these parameters, such as the Poynting vector (E x H*) for electromagnetic waves and the relationship between antenna gain and directivity. It also introduces related terms like mixers, which are critical components in antenna measurement instrumentation for frequency conversion (fIF = fRF +/-nfLO). The theoretical framework provided supports the scientific analysis of antenna performance, applicable to various antenna types and operational frequencies. DXZone Focus: Technical Guide | Electromagnetic Theory | Far-Field Region | G/T Parameter

This project is an attempt to build a portable standalone VNA (Vector Network Analyzer).

This article describes a low-cost vector network analyzer that operates from 200 kHz to 100 MHz, and connects to a personal computer using a USB 1.1 interface By Tom McDermott, N5EG, and Karl Ireland

VectorFox is a software born to incorporate a PC into the fox hunting environment. VectorFox is able to take inputs from up to 5 sources, such as a 2m beam, a 2m signal meter, a TDOA, etc, and display the results on the screen. VectorFox also accepts Agrelo inputs. From these results the operator can choose which indication is best and have a line drawn on the map in the direction of the signal.

60KHz to 60MHz. laboratory quality Vector Network Analyzer project

A vector graphic antenna analyzer project page by DC2WK demonstrating a project realized by DG7EAO includes, part list, schematics, and videos.

Homebrew VNA capable of both transmission and reflection measurements from 0.05 to 60 MHz

Metro Vector Network Analyzer is a custom antenna analyzer designed and produced by IZ7LDG.

Demonstrates a range of specialized radio frequency equipment and consulting services for amateur and professional applications. The offerings include _Vector-Finder_ direction finding antennas, various test equipment such as _gate dip meters_ and RF sniffers, and communications receiving adjuncts. Additionally, the company produces satellite antennas for weather satellite reception, voice amplification devices like the _Flex-Mike_, and custom prototype circuit boards. The company's product line addresses needs for precise RF measurement, signal detection, and specialized antenna systems, particularly for direction finding and satellite communications. Their historical association with National Radio (HRO) suggests a legacy in radio technology. The site also highlights a subsidiary, Sierra Mountain Products, which offers outdoor recreational gear, indicating a diversification beyond core RF manufacturing.

DG8SAQ Vector Network Analyzer and VNWA multiband antenna analyzer

A 500 kHz to 5.5GHz 2-port vector network analyzer designed for use with any Linux, Windows or MacOS computer. High performance: up to 80 dB dynamic range in the MHz range; up to 40 dB in the GHz range

In this article the author analyze six different type of VHF handheld antennas and as result of his self training on his new vector network analyzer published this interesting report

Operating a modern amateur radio station, particularly for advanced digital modes or microwave experiments, often requires precise test and measurement equipment. This resource from NI (National Instruments), now part of Emerson, showcases a wide array of hardware and software solutions designed for demanding test objectives. Their portfolio includes modular instruments and configurable software interfaces, such as _LabVIEW_ and _TestStand_, which integrate AI assistance via _NI Nigel™ AI_ for code completion and sequence building. For those involved in RF and microwave work, the offerings extend to vector signal transceivers, RF signal generators, software-defined radios, and spectrum analyzers. These tools are crucial for characterizing antenna performance, optimizing transceiver circuits, or developing custom radio systems. The company emphasizes its 50 years of innovation, with 40 years dedicated to _LabVIEW_, highlighting a long-standing commitment to engineering solutions. The site also details products for data acquisition, electronic test, and wireless design, covering components like CompactDAQ modules for precise sensor measurements and various communication bus interfaces. Their events and perspectives sections offer insights into topics such as 5G technology and strategies for breaking out of testing silos, providing a broader context for their measurement solutions.

Times Technologies Vector Impedance Analyzer Review

Magnetism is manifested as a 'field of vectors', that is, any point in the magnetic field has not only a magnitude, but a direction in space. The four Maxwell equations describe how electric and magnetic vector fields behave and interact.

KC901S Handheld vector antenna analyzer RF ANALYZER 3GHz S11 S21 Fieldmeter RF Source Spectrum

A calibration kit useful when you need known reference impedances to properly calibrate your vector network analyzers.

The NanoVNA is a very compact handheld Vector Network Analyzer. The NanoVNA is tiny and portable analyzer, and it offers a high performance capabilities with an embedded lcd display.

Very Tiny Palmtop Vector Network Analyzer by edy555. This is the original GitHub firmware repository implementing the standard 50KHz to 300MHz model

A collection of ham radio clip art royalty free. Additional amateur radio clip art can be found changing the search terms.

The mini Radio Solutions miniVNA PRO is the only affordable vector network analyser (VNA) I know of that offers remote wireless operation. This is very interesting because it allows to measure the input impedance of HF antennas installed at height without having to deal with coax cable lengths, baluns nor common mode suppression chokes. However, to render the miniVNA PRO truly field proof, it requires a number of significant modifications.

This article details the design and construction of a compact 20-meter QRP SSB transceiver by Pete Juliano, N6QW, measuring just 2 x 4 x 2 inches—small enough for a shirt pocket. Inspired by a 1963 QST design and refined from a prior version, it employs bilateral circuits, a 4.9152 MHz homebrew crystal filter, switched-crystal VXO for 60 kHz coverage (14.160-14.220 MHz), and standard components like ADE-1L mixers and IRF510 PA for 1W output. Key innovations include a double-sided PCB skeletal frame for shielding and isolation, Vectorboard sub-assemblies, and ultra-miniature relays. The bilateral receiver/transmitter shares stages, omitting AGC for simplicity, while a W3NQN LPF and optional 10W external amp enable DX contacts. Tune-up focuses on crystal matching and bias for linearity. Videos on YouTube demonstrate performance, confirming excellent stability and audio. Total cost nears $100, prioritizing portability over features like CW.

This article published on QEX details measurements of tree conductivity and permittivity at HF frequencies, addressing a long-debated topic in amateur radio. N6LF conducted experimental impedance measurements on Douglas fir and maple trees using a vector network analyzer with rings of nails inserted into tree trunks. Results showed that tree conductivity increases with frequency while relative permittivity decreases, similar to soil characteristics. Measured conductivity ranged from 0.06 to 0.4 S/m at 10 MHz, aligning with values used in previous research. These findings validate that NEC modeling can reliably estimate trees' substantial impact on HF antenna performance.

A common mode choke/balun, essential for mitigating common mode current on antenna feedlines, is detailed in this construction and measurement guide. It utilizes eight Fair-Rite #2643167851 Mix 43 ferrites housed within a Hammond 1598JSGYPBK plastic case, with RG-8X coax cable forming the windings. The document references design principles from Ian White, GM3SEK's article on cost-effective ferrite chokes. Specific construction details include the layout of three coils to minimize inter-coil coupling and methods for securing the ferrites with foam tape. The resource presents comprehensive measured data, including isolation impedance (magnitude, real, and imaginary components), Q factor, inductance, and phase angle across various frequencies. It also covers the choke/balun's coax frequency response and return loss characteristics. Techniques for measuring choking impedance are thoroughly explained, focusing on S21 transmission measurements with a Vector Network Analyzer (VNA) and testing ferrite beads in both S11 and S21 modes. The guide describes a practical setup using an aluminum sheet or baking foil for measurements and outlines the calculation of series impedance from attenuation in a 50-ohm system. Additionally, it details a method for determining the balun's equivalent L and C around resonance by adding a parallel capacitor.

Facilitates interfacing with various NanoVNA models, including NanoVNA-H, NanoVNA-H4, NanoVNA-F, AVNA, and LiteVNA, to extract and display measurement data on a computer. The application supports splitting frequency ranges into multiple segments, increasing resolution beyond the standard 101 data points, with reported tests achieving up to 10,000 points for detailed analysis. Data averaging is also implemented to improve measurement accuracy, particularly beneficial at higher frequencies where noise can be more prevalent. Displays data across several chart types, such as Smith, LogMag, Phase, and VSWR charts, for both S11 and S21 parameters. Markers provide specific readouts for impedance, VSWR, Q factor, and equivalent capacitance or inductance at selected frequency points. Users can define and display customizable frequency bands as reference overlays on the charts. Developed in Python 3 (specifically >=3.10), the software leverages pyside6 for its graphical user interface, numpy for numerical operations, and scipy for scientific computing. This robust framework ensures stable performance and accurate data processing for amateur radio operators and electronics enthusiasts performing antenna and circuit characterization.

HamVNA presents an alternative Vector Network Analyzer (VNA) software tailored for the Hermes SDR RX/TX board, enhancing its utility for analyzing antenna systems and radio circuits. The software processes measurement data from two distinct sources: direct acquisition via the Hermes hardware, leveraging fixtures like Sam Wetterlin's Series Fixture or reflection bridge, or by importing existing TouchStone format files (*.s1p, *.s2p) from other VNA hardware. It operates on Win2000/WinXP/Vista/Win7 platforms, supporting both 32 and 64-bit architectures. The program incorporates standard Open-Short-Load calibration for reflection mode and Short Circuit calibration for transmission mode, with the capability to save and reload calibration data. A key distinguishing feature is its RLC Fit function, which automatically generates an equivalent RLC circuit matching the impedance-vs-frequency curve of the Device Under Test (DUT), a capability noted as unique among VNA software. This function allows control over circuit complexity via an 'Order' slider. HamVNA also supports remote calibration, enabling the removal of coaxial cable effects from measurements for clearer analysis, as demonstrated with an 80m vertical antenna example. The software is an open-source project, distributed under the MPL v.2.0 license, with both the installation package and source code available for download.

Presents a Windows software application specifically engineered to interface with NanoVNA vector network analyzers. The application's source code reveals modules like Calibration.cpp and GraphUnit.cpp, indicating robust functionalities for VNA calibration procedures and graphical visualization of RF measurement data. It supports various NanoVNA firmware versions, including NanoVNA H v1.2.24.dfu and NanoVNA H4 v1.2.24.dfu, ensuring broad compatibility across popular hardware iterations. Key components such as BatteryVoltageUnit.cpp, ColourPickerUnit.cpp, and SerialPort.cpp manage battery monitoring, user interface customization, and serial port communications, respectively. DataUnit.cpp handles measurement data processing, while SettingsUnit.cpp provides comprehensive control over application configurations, allowing hams to tailor the software to their specific analysis needs. The project integrates USB100.H and USBDI.H for direct USB connectivity and TCPIP.cpp for network-based communication, offering flexible options for connecting to NanoVNA devices. This software streamlines the process of analyzing and interpreting RF characteristics, making it a practical tool for antenna tuning and circuit analysis.