Free and not so free software for electronics and PC's.

electronics tutorials for ham radio

Shop for software at



atlc - Arbitrary Transmission Line Calculator

atlc is a computer aided design (CAD) package for the design and analysis of electrical transmission lines and directional couplers of totally arbitrary cross section and an arbitrary number of different dielectrics. By analysis, it is assumed one requires finding the electrical properties of a transmission line or coupler, where the physical dimensions of the device are known. By design, it is assumed one requires a transmission line or coupler to have certain electrical properties and one wishes to find how to physically realise such a structure.

atlc likely to be of use to radio amateurs, professional RF engineers, students and academics.

From the author - Dr. David Kirkby

"I found your site at and are writing to ask if you would like to add a link to a free UNIX or Linux program for analysis and synthesis of transmission lines of arbitrary cross section."

"The code is very portable and have even been run on a Sony Playstation 2" - by someone else, not me!!

"It should work on any UNIX or Linux system and will support multiple processors if the computer has more than one CPU."

Get it here -



suggest us to a friend

NTE QUICKCrossTMVersion 9.0

NTE Cross Reference Software. NTE require completion of a registration form but that's no burden and the software is FREE

NTE Cross Reference Software

suggest us to a friend


Stricly speaking not a download but a helpful calculator page where you enter the numbers. "This calculator is designed to model the common configuration where a transmitter which is designed for a particular load impedance, is connected to a an antenna of that impedance, over transmission line of the same characteristic impedance".

VSWR Calculator

suggest us to a friend

Motorola Impedance Matching Program - FREE

Motorola's Impedance Matching Program is a specialized form of CAD specifically developed for RF power amplifier circuit design. It provides a simple environment for entering and analyzing impedance matching circuitry regularly employed in RF Power amplifier design.

Data sheets for RF devices contain large signal impedances (measured at a single combination of frequency, voltage, power level and power dissipation). These impedances must generally be transformed to another set of impedances (50 W or the input/output impedance of another device). To do this, MIMP provides a standard library of passive circuit elements; including various combinations of capacitors, inductors and transmission lines in both series and shunt configurations. It also contains a unique, DISTRIBUTED CAPACITANCE ELEMENT that models a capacitor distributed along a transmission line. - 119K

suggest us to a friend

Micrometals RF Design Software

Micrometals FREE RF design software, RF-Toroid was written as a supplement to the Micrometals RF Application catalog. Much emphasis was put into calculating the location of the Self resonate frequencies for series and shunt inductors. RF-Toroid is for use DC to 300 MHz. Much research went in to the calculation and corrections from the standard formulas for low perm & phenolic cores to better predict the RF style of winding and application. Some features include SRF for series and shunt cores, peak Q curve ranges and 200 & 360 degree coverage to achieve the best product possible for the microwave designer who needs accurate and abundant information at the finger tips to compare one core to another simultaneously. The custom core feature allows for custom shaped cores, stacking cores side by side , ferrite cores and machining custom phenolic cores from plastic, wood, ect... Micrometals hope this tool will serve you well.

Download Micrometals RF Design Software - 397 Kb

suggest us to a friend

Copyright Ian C. Purdie © 2000 - 2001 - 2002, all rights reserved. URL -

All material at this site may be used by private individuals for their own non-commercial purposes. Single copies of my pages or files may be distributed to other private individuals at no charge, unless other requirements are noted on the relevant page. However, all material remains the intellectual property of Ian C. Purdie, individual contributors, or other sources who gave permission for use of their material at this site. All copyrights and trade marks are reserved by myself or the respective owners. Material may not be republished without prior written permission, nor may it be mirrored on another server without my prior written permission. Other than as provided in these pages or permissions given, translation into another language other than english and hosting pages in another country is stricly prohibited.
Commercial use prohibited without the prior written permission of

Created 20th January, 2002

Updated 30th May, 2003

contact webmaster