R500/7T computer was built by Christof Traber. It is built from about 500 electromechanical relays and performing about 7 instructions per second. The computer was developed and built between 2001 and Oct 2006

Dr. Christof Traber is a former professor of computer science at the Swiss Federal Institute of Technology and currently a senior engineer at SVOX AG specializing in speech synthesis technology.

The computer is driven by 24 VDC. The power supply is a conventional 230 VAC to 24 VDC transformer-rectifier-condenser unit. Actually, the unit turned out to be somewhat oversized, since it could provide 20 Amps @ 24 VDC, whereas the computer does never consume more than about 4 to 5 Amps. Most people are surprised to hear how small the power consumption of the machine is (only around 100 Watts at maximum).

Computer architecture: