Fans of the 15C want Hewlett-Packard to put it back in production. Find a list of reasons to bring it back, the reason it was discontinued in the first place, and an online petition.

The private collection of the Dutch collector Nico Baaijens of mechanical, electro-mechanical and electronic counting, adding and calculating machines. Many pictures and close-ups.

Webring designed to allow navigation between similar sites dealing with the hobby of collecting, and history of electronic calculators.

Technical information about many calculators, including chip pinouts and self-test sequences, and patent information.

A collection of early mechanical calculating machines and other calculating devices.

Technical information about hardware, interfacing, and programming of this vintage device. Includes a construction project for a storage device to emulate the original FA-3 cassette interface.

Calculators from the '70s, and famous home and personal computers from '80s. Photos, historic information and links to other resources.

Links to useful sites about the Curta. Also documents the full disassembly of one, with pictures.

An overview of the calculators manufactured by Texas Instruments Inc. from the famous Datamath (1972) to the modern Graphics calculators, with history and articles.

A source of information about the technology used in the construction of early electronic calculators. Includes a reverse-engineering project.