ELANAG

I have the most wonderful friends in the world! This analog computer, which is one of the most beautiful portable analog computer I have ever seen, was donated by my friend Frederic Fournis. I am deeply indebted to him for this incredible gift.

The pictures below show details of the machine. First of all it is mounted in a custom made, sturdy carrying case which features some connectors on its rear.

The top lid holds the power cord as well as the very special patch cords as seen in the picture on the left. The picture on the right shows the patch panel of this wonderful machine:

The analog meter mounted in the middle of the machine can be used to measure voltages during a computation as well as for setting up the coefficient potentiometers using a compensation method (which unloads the potentiometer being set thus eliminating any setup error due to load current). The picture on the right shows the internals of the computer. The bottom half of the enclosure holds the main transformer on the left and a rather large choke on the right. The four printed circuit boards are voltage regulators. The top half contains the ten computing elements: Five summers and five summers/integrators (the mode of operation can be selected by switches).

The picture below left shows a closeup of three of the summer/integrators. Clearly visible are the foil integration capacitors and the AD 106C operational amplifiers. The relays are for mode control (initial condition, operate and halt). The picture on the right is a closeup of the patch panel showing the special plugs and jacks. Please note that the patch cables have a plug and a jack on their respective ends. As strange as this may seem, it is a brilliant idea as it makes it impossible to patch an electrically erroneous program. It is (more or less) impossible to connect two outputs.

More pictures and descriptions will follow as soon as this beautiful machine will be restored and put back into operation.

12-JUL-2015, ulmann@analogmuseum.org