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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

Easy Quad calculator, enter center frequency to get a quad antenna size

A circular waveguide calculator for designing cantennas include source code and windows executable by lincomatic

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

Various radio related software, including some antenna analysis, and impedance calculators.

This is a simple calculator for solving the antenna wire catenary between to end points given the design wind speed, mass per unit length of the wire, wire diameter and Gross Breaking Strength of the wire.

Simple implementation of the ARRL Antenna Book design equations for the axial-mode helical antenna.

Ham Radio 20 / 40 meter short Coax Trap dipole antenna designed with the coax trap design calculator program

LCF online Calculator, calculate relation between Frequency Capacitance Inductance and Reactance

Online calculator and construction instructions

Online Yagi Uda antenna calculator

This calculator computes the matched line loss for a transmission line using a model calibrated from data for the transmission line types built in to the calculator. It also gives an estimate of the mismatched loss if the mismatch is specified.

Yagi Calculator is a free Windows program that also runs well on Linux, Ubuntu 8.10 under Wine, to produce dimensions for a DL6WU style long Yagi antenna. Long yagis are commonly used from the 144MHz amateur band to the 2.4GHz band.

The easy way to calculate toroid cores.

Helical antennas invented by John Kraus give a circular polarized wave. They are one of the easiest to design. Find a tube with a circumference equal to one wavelength, and wrap wire in a helix spaced a quarter wavelengt

A simple online folded dipole antenna calculator

A magnetic loop antenna calculator made with an excel sheet that run also with open office, let you design mag loop antenna dimensions by AA5TB

Excel spreadsheet that help calculating dimensions of a high efficiency magnetic loop antenna for HF bands. Giving in input the loop perimeter, loop diameter and loop conductor will calculate electric characteristics, bandwidth, and efficiency

Online helix antenna designer, calculate size of helix antennas online

Computes the Standing Wave Ratio, given the power readings on a line.

Online antenna calculator for cubical quad antennas by EA1DDO / HK1H

Online calculators for toroid coil, air-core coil inductance, XL, XC, and more.

This calculator is designed to give the efficiency loss of a given antenna, based on the input of VSWR (voltage standing wave ratio) and other subsequent factors

This online calculator computes the great circle distance between two points on the earth's surface

This web based application will compute circuit values required for an L-C circuit to resonate at given frequency. Also it will compute the resonant frequency if given values for L and C.

Presents a dynamic, searchable database of shortwave broadcast schedules from around the world, enabling users to locate active stations or plan listening sessions based on scheduled transmission periods and frequencies. The resource details specific station names, such as _Radio Habana Cuba_, _Deutsche Welle_, and _All India Radio_, alongside their operational times and assigned kilohertz frequencies. It also incorporates a distance calculator, which leverages geographical coordinates to estimate propagation paths, though it notes occasional data inaccuracies leading to transmitters appearing in oceanic locations. The platform's development log highlights continuous updates, including the integration of new seasonal schedules like "A24 frequencies" and "B23 schedule," reflecting the fluid nature of shortwave broadcasting. It documents challenges with geolocation services, particularly concerning Google API changes that impacted distance calculations and required user-side browser configuration adjustments for optimal functionality. The site owner, VAXXi, frequently communicates these technical adjustments and database updates, often acknowledging user contributions and donations. Distinctively, the resource provides a historical perspective through its update archives, illustrating the evolution of shortwave listening over more than a decade since its inception in 2011. It also mentions specific events, such as the BBC adding shortwave broadcasts for Ukraine on 5875 kHz and 15735 kHz, demonstrating its responsiveness to global events impacting broadcast schedules. The site's commitment to user feedback is evident in its bug reporting and feature request mechanisms, contributing to its ongoing refinement.

HAMIC, is a program designed to simplify a number of calculations commonly used by HAMs. It is designed for the HAM radio hobbyist, but may be useful to others as well. HAMIC has a simple to use, but powerful graphical interface that allows solving simple circuits such as resistors in series or parallel, or more complex circuits such as L networks or T networks. As well, other calculations such as SWR and reactance conversions are supported. Windows shareware.

An inverted Vee antenna calculator that consider also minimun vertical height and horizontal spread by M0UKD

Unix or linux programme atlc calculates the impedance of electrical transmission lines of totally arbitrary cross section.

The Top-Rated Electrical and Electronic Engineering Calculator for Palm OS

Does your Amateur Radio system comply to the EMI rules ? (German values implemented)

Accurately determining an antenna's feedpoint impedance is crucial for optimal performance, especially when experimenting with new designs or making adjustments. While SWR meters provide basic information, a full complex impedance measurement reveals the resistive and reactive components, which are essential for proper matching. Modern antenna analyzers, like the _Palstar ZM30_ or MFJ259B, simplify this task, but measurements taken through a transmission line require careful interpretation due to impedance transformation. This resource details a calibration method to precisely account for the effects of the feedline. It explains how a transmission line can significantly alter the measured impedance, illustrating this phenomenon with a Smith Chart example where an 80m antenna's [22 + j6] Ohms feedpoint impedance transforms to [82 + j45] Ohms after a 10m line. The guide demonstrates using a transmission line calculator applet, such as the one by W9CF, to reverse this transformation. It outlines the process of calibrating a specific length of RG174 coax, showing how an initial 26ft estimate was refined to **25.85ft** to accurately predict a known 22 Ohm load, significantly improving accuracy over uncalibrated results.

A javascript online calculator for popular wire antennas, from the standard easy to build flat-top dipole, to the inverted V dipole, but also the Quad Loop, and the equilateral delta loop antenna

Calculate power loss depending on coax cable you use

This online microstrip patch antenna calculator determines the length and width of a microstrip patch antenna for a given frequency

Helix antenna online calculator with match calculator

An online J-Pole antenna calculator that need just to input the frequency and calculates in inch size of each element

Build an effective dipole antenna that needs much less space by adding two loading coils. This online calculator tells you how.

This calculator is designed to give the vertical length of a quarter-wave ground plane antenna, and the length of each of the four radials for the selected frequency you have entered

A windows impedance calculator software by VK3UM

Microstrip Patch Antenna Calculator determines the length and width in millimeters of a rectangular patch antenna.

Calculating HF helical whip antenna for mobile or portable operation

A page by 9A7PJT dedicated to HB9CV yagi antennas includes link to the HB9CV calculator program and some interesting plans

This calculator is designed to give resistor values for unbalanced T-pads, and for balanced H-pads.

This page allows you to calculate in the most accurate way high-Q inductor coils.

This calculator is designed to give the horizontal length of a particular dipole including Tees, antenna, or one side of it, for the frequency chosen. Enter the desired frequency and select the desired calculation from the drop box

An online javascript calculator for cubical quad antennas, simply input the resonating frequency to calculcate up to a five element quad antenna. This quad antenna calculator let you determine the total length of each element and spacing among elements.

Ever need a way to estimate the amount of wire to add to or remove from a center-fed wire dipole antenna to achieve resonance at a desired frequency? This article help to determine correct wire lenght.

W0FMS Two-Wire Beverage (SWA) Transformer Calculator

Constructing a compact, single-feed triband Moxon antenna for 20, 15, and 10 meters is detailed by DU1RZ, drawing from his personal experience with space-constrained antenna projects. Initially fascinated by cubical quads, the author transitioned to Moxon designs in 2005 after realizing his roof space was insufficient for a bulky quad. His first experimental monoband Moxon for 15 meters, built from repurposed materials, provided solid DX QSOs for seven years, despite being slightly below the 21 MHz band center. The project outlines the design process, including using the _MOXGEN Calculator_ for element dimensions and material selection, such as #14 AWG enamel copper wire and fishing poles for spreaders. DU1RZ shares insights from simulations with DL2GMS regarding insulated versus non-insulated wire performance, noting that insulated wire can shift resonant frequencies lower. The assembly instructions cover preparing wire elements, connecting feed points, and tuning the antenna, with initial SWR measurements taken at 10 feet and final readings on a mast showing excellent results: 1.0:1 on 14.225 MHz, 1.1:1 on 21.250 MHz, and 1.3:1 on 28.50 MHz. Transmission tests with 4F1BYN indicated a front-to-back ratio of approximately 2 S units with 10 watts output. The author emphasizes adaptability, encouraging builders to use readily available materials rather than strictly replicating his setup. Key observations from DU1RZ and DL2GMS highlight the antenna's strong performance across 20, 15, and 10 meters, good front-to-back ratio, full bandwidth on 20 and 15 meters, and its small turning radius of about 4.18 meters (13.54 feet), making it suitable for limited antenna space. Its lightweight construction and low wind load are also noted as significant advantages.