Z22 (computer)

The Z22 was the seventh computer model Konrad Zuse developed (the first six being the Z1, Z2, Z3, Z4, Z5 and Z11, respectively). One of the early commercial computers, the Z22's design was finished about 1955. The major version jump from Z11 to Z22 was due to the use of vacuum tubes, as opposed to the electromechanical systems used in earlier models. The first machines built were shipped to Berlin and Aachen. By the end of 1958 the ZMMD-group had built a working ALGOL 58 compiler for the Z22 computer. ZMMD was an abbreviation for Zürich (where Rutishauser worked), München (workplace of Bauer and Samelson), Mainz (location of the Z22 computer), Darmstadt (workplace of Bottenbruch). In 1961, the Z22 was followed by a logically very similar transistorized version, the Z23. Already in 1954, Zuse had come to an agreement with Heinz Zemanek that his Zuse KG would finance the work of Rudolf Bodo, who helped Zemanek build the early European transistorized computer Mailüfterl, and that after that project Bodo should work for the Zuse KG—there he helped build the transistorized Z23. Furthermore, all circuit diagrams of the Z22 were supplied to Bodo and Zemanek. The University of Applied Sciences, Karlsruhe has an operational Z22 which is on permanent loan at the ZKM in Karlsruhe. Altogether 55 Z22 computers were produced. In the 1970s, clones of the Z22 using TTL were built by the company Thiemicke Computer.