VVB RFT Radio und Fernmeldetechnik
Leibzig, GDR

The RFT-Kombinat of the former GDR (German Democratic Republic) produced already in 1973 the first electronic calculators. Most of the
early calculators based on designs introduced by Texas Instruments or Toshiba. Later products were OEM-products from Japan supliers. 

Source : Joerg Woerner, Datamath Calculator Museum