überarbeitet am 20.6.2014
The Dr. Edgar Gretener AG has been founded at Zurich -
Altstetten in 1943, they started business with a video
projection system called "Eidophor" developed together with
After Dr. Gretener deceased, the company has been renamed Gretag AG in 1958; and
the companies headquarters were relocated from Kleinstrasse, Zurich to new premises in Regensdorf ZH, where Gretag
resided for many years. They developed automatic encryption
systems as well as a colour separation system for the printing
One of the first developments was the famous
ETK, Einton - Kombinationsschreiber,
a combined letter printer. In contrast to the standard
teletypewriter Baudot code, this machine used a special code combining one letter
from several out of fourteen different segments, which made message transmission more
reliable, as letters remained still legible, even if one
or two of the segments were missing.
After he had settled down in Switzerland, the famous inventor
of ciphering machines Boris Hagelin, who had been living
in Sweden before, had a short time of cooperation with
Edgar Gretener in 1948, before he founded his own company
"Crypto AG" located at Zug in 1952, which is still in business today.
The Gretag developed a automatic ciphering machine matching
the fourteen segment ETK
printer shortly after, this was the automatic cipher machine
transmission quality was quite reliable over telephone lines -
when wireless connections were used, the automated encryption lost
synchronisation quite often, when the shortwave communication
suffered from fading.
This situation became much better, when Gretag came out with the very
Kryptofunkfernschreiber KFF, which provided
automatically encrypted radioteletype transmission with
automatic synchronisation, specially in connection with
Zellweger's compact SE-222 single sideband transceiver.
Any machines using the ETK fourteen segment code remained without
commercial success outside Switzerland, Gretag developed
the Telecrypto 61 ciphering
teletype messages using the Baudot code.
Later on, Gretag produced a large number of electronic
ciphering devices called "Gretacoder"
In the early nineties, the cryptology segment of Gretag AG has been
split off and became Gretag Data Systems, in 1995, it changed name to become
Gretacoder Data Systems AG.
The company has been taken over by an American investor and changed name
for Safe Net Data Systems AG, even with some new investments, this company
did not survive and ceased operation in late 2004.
Most patents of Greacoder AG went into possession of Omnisec, this company was
also resident at Regensdorf ZH.
© Martin Bösch, 26. Dez. 2011