article · English
The Telefunken RA 770 Analog Computer
A first-person account (dated December 2007) of acquiring, restoring, and documenting a Telefunken RA 770 high-precision analog computer (accuracy 10^-4, weight ~550 kg). The article describes mechanical and electrical restoration after rodent damage, and covers major subassemblies including dual power supplies, the DBG 771 digital control drawer with oven-stabilized quartz oscillator, chopper-stabilized OP14 operational amplifiers, servo potentiometers for coefficient setting, non-linear network drawers (NNT 771), variable function generators (VFG 801), and the coaxial analog patch field.
analog computer restorationRA 770chopper-stabilized amplifiersservo potentiometers