XTRON

Electronics Expert System

© 1998-2018 by Tom Ahola

  0; Back to Tom's calculators
1: Voltage, current and power
2: Resistance
3: Passive AC and transient circuits
4: Power management
5: Transistor circuits
6: Operational amplifier circuits
7: RF and high-speed circuits
8: Components

Welcome to Tom's Electronics Expert System pages! I started making web based calculators for electronics in 1998. Previously I had made electronics calculation programs for my Sharp pocket computer/calculator. Javascript was more advanced than the Basic language in the pocket computer. In 2001 or 2002 I started using the Nokia 9210i Communicator. My calculators could be stored locally in the communicator and I made a special script that allowed pressing keys 0...9 to enter a menu item. This was handy because there was no touch screen and moving the cursor around the screen with the cursor keys was slow. This functionality is still there. Try it, if you have a keyboard, by pressing a number key to enter that menu item. You can use backspace key to get back from the calculator itself to the menu again.

I never made my calculators public. They were just tools for my own electronics design work. Now in 2018, 20 years has passed and to celebrate this I have finally made my calculators available for the public. In addition to these electronic calculators I have many more calculators for other topics such as unit conversion, mechanics and other handy tools for everyday use. Check them out too: Tom's calculators

Note that most of my calculators use SI units because that are the units I use in engineering. I don't know if I will later add a possibility to select imperial units, where needed. The values are always in base units but in most places you can add a suffix in the value field. For example to enter 56000 ohms, you can type 56k in the field. Or, 0.023 volts can be typed as 23m.