Museum for the historical development of calculator, computer and communication technology

Exemplary programmable second-generation calculators

Second-generation calculators did not have integrated circuits yet. This made it difficult to build efficient calculators, so programmable calculators of that species are technically especially interesting. Already in 1966, DIEHL put such a calculator on the market. The operating system is "booted" from a metallic paper tape and application programmes are stamped on paper tapes that can be read in again. Probably the Stone Age of programmable calculators! Such complete installations are very rare.

Diehl Combitron

Diehl Combitron

The Combitron is the first operating programmable desk calculator that was built and sold in Germany. On the right you can see the DIEHL Dilector (paper tape reader) and to the left is the DIEHL ELS 830 (paper tape puncher). The system is fully operational. The delay line memory serves as storage media (capacity ca. 1000 bits).

Olivetti Programma 101

In the same year the Olivetti Programma 101 came onto the market. For the first time in EDP history, engineering offices were able to buy a "small" calculator on which you could quickly save own programs on magnetic cards. This machine with many mechanical parts, became a big seller. However, the device was very expensive, but the price of 14800 DM + fees (ca. 8000 Euro) paid for itself in saved manual calculating time.

Programma 101

The legendary PROGRAMMA 101 by Olivetti. In the middle you see the magnetic program card. Delay line memory was used as storage media.

WANG 320

The WANG 320 is an outstanding machine in the collection. It was built in 1967 and is extremely rare nowadays. The system can be programmed using punched cards and features multiple keyboards, a sensational feature in its time.



In 1966/1967 the WANG 320 SE was a flagship calculator. Two of its features were truly sensational for its time: It could calculate logarithms and anti-logarithms quickly (in fact this took less time than the calcultion of a square root) and up to four keyboards could be connected to a single calculator unit; thus the machine was in fact a time sharing system. Further more the system could be programmed using punched cards – running programs were suspended for a short period of time to allow interactive users access to the machine. The 80 column punched cards could be prepared manually using a stencil. These features made the calculator a perfect match for schools and universities. While the slide rule was in use in most of these places, this machine allowed them to enter the field of computer science.
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Hewlett Packard HP 9100


HP 9100

In 1968 the first desktop calculator made by HP hit the market and was a truly outstanding machine. All of its internal logic is implemented using discrete transistor logic without a single integrated circuit. The machine supports a wealth of mathematical and scientific functions and employs a magnetic core memory, so even after a power off the contents of memory (data and programs) are preserved. Magnetic cards serve as external storage media. The printer shown on top of the HP 9100 is an optional device. The heart of the display is a CRT on which the contents of three internal registers are displayed. The character generation is controlled by a wired ROM. This technological marvel indeed had its price – with a price of 23 000 DM for the basic version it was not affordable for individuals.
Only two years later WANG brought the WANG 700 to the market in direct competition to the HP 9100.

display of the HP-9100

Closeup of the HP 9100 tube display

Read further details at the tabular overview of desk calculators