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



The technikum29 is quite versatile – beside all the communication and computer technology we also show very special exhibits: This is a fully executable pianola, year of manufacture about 1910-1915.

It's a great experience see and hear such old jukeboxes, typically made only of natural materials like leather, gum, wood, bone glue, felt, metal, paper, ivory and glas.
By assembling these elements on an intelligent way, one could build a simple mechanical machine which is especially impressive for today's people. Here at the technikum29, we will show you how this device works, we will explain the basic functionality and play challenging compositions. While having covers removed, you can even see the fascinating mechanics working.

Picture of the Pianola

Movie projector "Dresden 1"

Photography of the movie projector Dresden 1

The technikum29 has a movie projector from 1951 (there are more and even older projectors from the 1930s that are stored in the archive for lack of space).

Movie projectors have always been very complex devices. At that time, the bright picture projection was archived with an arc light which was generated between two carbon pencils. The waste heat was deflected via a chimney pipe! Since the pencils got shorter and shorter while the movie went on, they had to be moved continously closer together for producing a constant luminosity. Otherwise the light goes out.
We will repair this device to show an original newsreel from the 1960s.

Siemens Demonstration Computer

Siemens demonstration educational computer CPU

Siemens educational computer

This demonstration model was build in 1973, when personal computers were not invented for a long time yet. Engineers had to be trained to understand computer architectures. Therefore, this big education model was constructed. It is a giant implementation of a typical register machine where 126 lamps display all registers, control, ALU and RAM, including the data flow. Featuring a mutable clock pulse and only 4 bit word with, elementary opcodes could be reproduced in a very illustrative way. The device can be toggled to process one instruction or one cycle a time.
On the left side, the computer program could be directly "written" by plugging cartidges labeled with assembly instruction mnemonics or numerical values (immediate operands). On this cartiges the user could directly read the binary value of the machine instruction which will be the content of the corresponding random access field. As you might guess, the computer cannot change the program memory without user interaction, so this model actually implements an Harvard architecture, even though the (german) labels on the frontend suggest something different.
The picture above shows a currently running program that adds memory cells. It shows that computer word lengths do not limit the length of proccessable numbers.
It is a wonderful device that can even be used today to understand the elementary workflow of modern high end desktop CPUs.