This Guy Built His Own Analog Computer
Markus Bindhammer fulfilled a childhood dream by building his own analog computer.
The entire world is built on digital computing — Boolean algebra represented by true or false, one or zero, and high or low. We settled on that because it is incredibly scalable; you can keep adding transistors to build as many logic gates as you want. That’s why modern processors have literally billions of transistors and are so powerful. But analog computing is also thing and absolutely fascinating, which led Markus Bindhammer to fulfilling a childhood dream by building his own analog computer.
Analog computers can be hard to understand. If I’m being honest, I don’t truly comprehend how they work in practice. But we had analog computers long before we had digital computers. Even the humble slide rule, which has existed for about 400 years, is a type of analog computer.
Bindhammer’s homemade analog computer is electric and something similar to what was being made in the 1960s and 1970s, just before personal computers became affordable. It seems to take particular inspiration from the Heathkit EC-1.
Functionally, this is all about comparing and manipulating analog voltages. To that end, the “displays” are a pair of needle gauge voltmeters and an oscilloscope. It would have been cool if Bindhammer had used a CRT (Cathode-Ray Tube) oscilloscope, but that wouldn’t have been very practical, so he used a simple and inexpensive digital model.
Like the Heathkit EC-1, the user operates the computer by running cables between points, similar to patch cables on audio equipment, and adjusting voltages with potentiometers. Those cables have banana plugs, so they’re easy to insert and, more importantly, can be stacked to attach multiple cables to single point.
To perform an operation, like adding, the user patches the reference voltage to a specific amplifier used for adding another voltage. The resulting sum voltage can be viewed on a separate multimeter, the built-in voltmeters, or the built-in oscilloscope.
Other functions are also possible, but we’ve already exceeded my understanding of analog computing. So, I’ll leave you to enjoy Bindhammer’s video for a better explanation.