D4a

Small computer D4a in the Heinz Nixdorf MuseumsForum

Magnetic drum storage of the D4a - the large drum (vertical with tangled cables ) comes from the ZRA1 , the D4a modification based on the same construction principle is at the front and bottom across.

The small computer D4a (a for "disarmed") was a type of computer from the GDR .

Like its predecessors D1 , D2 and D3 , it was developed and manufactured at the TU Dresden under the direction of Nikolaus Joachim Lehmann .

The D4 was entirely transistor based . He had about 200 pieces with which he could perform 2000 operations / second. Its drum memory had 4096 memory cells with 33 bits each . The D4a had an integrated keyboard and punched tape reader as input devices, and a tape printer was used for output. In the D4a version, the computer was one of the first desktop computers in Europe.

From 1966 about 3000 pieces of the D4 / D4a were produced in series by VEB Büromaschinenwerke Zella-Mehlis .

Web links

• Miniature computer D4a , association for the technical collections in Dresden
• D4a on robotrontechnik.de