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

SimSmith is a highly interactive, real time Smith chart graphing program. Circuits are constructed using drag-n-drop. Load files can be imported from the EZNEC and CocoaNEC antenna simulation software and from the AIM4170 and miniVNApro antenna analyzers. Circuits and load files can be of any size. Key Features: SimSmith is one of the few Smith chart packages which models transmission line losses. SimSmith also allows the description of circuit elements using algebraic equations. SimSmith has only one screen and allows the screen to be resized to increase workspace or readability.

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

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

Enables Android users to operate various _miniVNA_ antenna analyzers via Bluetooth, USB, or Wi-Fi, providing a portable solution for RF measurements. The application supports full control over data acquisition, offering features like custom frequency range selection from 1 KHz to the VNA's full range, and automatic screen adaptation for diverse Android device resolutions. It facilitates intuitive, wizard-based calibration for both reflection and transmission modes, saving calibration data for different VNA types (Standard, Pro, Pro with Extender) to avoid repeated procedures. The software displays critical parameters such as SWR, |Z|, Return Loss, Phase, Rs, and |Xs| on 2-axis graphs or Smith charts, with multi-touch gestures for zoom and frequency shift. It includes a frequency generator mode with independent channels and attenuator control for the miniVNA Pro, along with a sweeper function. The cable data mode automatically calculates phase and loss, measures cable length from less than 1 meter to hundreds of meters, and includes a table of common coax cable velocity factors. An experimental X-tal mode measures resonance frequency, Rs, and Q. Data export options include CSV, ZPLOT, and S1P formats, with CSV import capability. The application also features an SM6ENG Audio mode for SWR tuning without visual reference and provides a miniVNA battery voltage indicator. It supports a wide frequency range, with the miniVNA Extender extending coverage up to **1500 MHz**. The application is compatible with Android version 2.2 and later, tested on devices like the _Galaxy TAB 7.7 P6800_.

Notes on installing the miniVNA PRO software, making a calibration standard, a trap tuning loop.

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.

VE2AZX's 2013 Radio Talk presentation details the technical aspects of baluns, including reasons for their use, various types, and methods for performance verification using an SWR analyzer. The document specifically examines 1:1 voltage baluns and 4:1 voltage baluns, outlining their winding configurations and typical impedance transformations. It presents empirical SWR measurements for W2AU 1:1 baluns and Unadilla 4:1 baluns, tested with both 50-ohm and 200-ohm resistive loads across the HF spectrum. The presentation further explores the measurement of ferrite impedance and their application in mitigating common-mode currents on feeders and household conductors. Key concepts addressed include balanced-to-unbalanced transformation, ensuring feeder independence from the antenna, and reducing unwanted feeder radiation. The content emphasizes practical testing procedures to ensure optimal antenna system performance and minimize RF interference. Discussions also cover open-circuit tests with SWR analyzers and VNAs to assess winding inductance, distributed capacitance, and insulation quality. The presentation differentiates between voltage and current baluns, explaining how current baluns, particularly those utilizing ferrite cores, reduce outer shield currents without affecting internal coaxial cable currents, thereby preserving the antenna's intended radiation pattern.