Edgar Gretener

He studied electrical engineering at Swiss Federal Institute of Technology (ETH Zurich), where he received his Ph.D. in 1929.

There he got in contact with Fritz Fischer (physicist), another Swiss engineer, working as a manager at the central research labs of Siemens.

When Fritz Fischer got the call to become professor at the ETH Zurich in 1932, he made Gretener his chief assistant a few years later.

When World War II started, the Swiss authorities asked Gretener to develop an encryption device for teleprinters.

The untimely death of Gretener in 1958 led to the renaming of his company, which continued under new ownership as GRETAG AG.