The MADDIDA (Magnetic Drum Digital Differential Analyzer) was a special-purpose computer developed by Northrop in the late 1940s. It was designed to solve systems of ordinary differential equations for guidance systems. It was a digital computer using Boolean algebra and used voltages to represent data bits.

These two brochures describe the MADDIDA system. The first is a MADDIDA preliminary report from May 1950. Click on the image to view the PDF. The second is the MADDIDA brochure.

These photos of the the MADDIDA system all feature a Tektronix Type 511AD oscilloscope. This first photo is a customer demonstration of the MADDIDA system.

Photo courtesy of Northrop

This photo shows two  MADIDDA systems.

Photo courtesy of Northrop

This photo shows a MADDIDA system and Sally Stephens operating a Marchant calculating machine. Note that this is the first version of the Type 511 oscilloscope which has the external graticule lamp and the single sweep speed dial.

Photo courtesy of North American Aviation