Toroid is the most complete iron powder core program on the market today. It was designed by microwave engineers to provide filter, radio,microwave and Ham radio engineers with all relevant information of an inductor and core at his or her finger tips. We hope this tool serves you well.source

MiscEl or Miscellaneous electronic calculation is the program contains a lot of pages with different electronic calculations. Each page contain one or more different calculations including OHM’s law, 3 Phase, Color codes, LEDs, Power supplies, PCB calculations, and many others. It also has some related to weather, geometry, photography and sound. It runs under windows.The program is free to download and use.source

Electronics Assistant is a Windows program that performs electronics-related calculations. It includes a resistor colour code calculator, resistance, capacitance and power calculations and more. Details of calculations can be saved or printed. It provides all the functions found in the calculators section of this site and more in a stand-alone user friendly program.

features:

• Updated user interface
• Extra calculators for inductance and frequency
• Calculation of nearest preferred resistor values with a choice of 5 series from E12 to E192
• Links to open Windows Calculator and up to 3 user-defined programs from Electronics Assistant
• Information panels can be toggled on or off to save space when not required
• Built-in automatic new version update check
• Various bug fixes and enhancements

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With firgen you can design Digital FIR (Finite Impulse Response) filters for the DSP (Digital Signal Processing) starter kits from Texas Instruments and Analog Devices.The program calculates the impulse and frequency response for a requested frequency curve and window function. The result is plotted and can be saved in source code for the TI or AD assembler.Usage is quite simple, first choose ‘New filter…’ from the File menu. Then enter the filter type, number of taps, window function and frequencies. Some filters work only with an uneven number of taps. source

THERMISTOR CALC is TEMPERATURE COMPENSATION CIRCUIT DESIGN SOFTWARE FOR NTC THERMISTOR / RESISTOR NETWORKS.A professional tool for design professionals.Graphically displays inverting, non inverting, and passive network only results .You can Analyze NTC thermistor networks with 1, 2 or 3 resistors.Extend the linear range of low cost NTC thermistors.Easy to use. Nothing to learn. source