It’s easy to take technology for granted — students frequently take notes on their laptop or review material from their cell phone before an exam. And although this wasn’t always the case, Penn State created something that played a major role in helping us get there: the first digital computer built and operated on a college campus.
In 1953, Professor Harold Tarpley led a group of faculty and students in developing Penn State Automatic Computer (PENNSTAC). Tarpley had already supervised the construction of a five-analog computer during his time on campus. Once he saw digital computers replace five-analog computers throughout different computer labs, he quickly formed the idea to jumpstart PENNSTAC.
Tarpley and Arthur Waynick, head of the Electrical Engineering Department, decided not to buy a digital computer (which would cost $300,000 at the time). Instead, the pair decided to both design and build their own. Tarpley and Waynick were able to secure $25,000 in university funding, as well as $17,000 from the National Science Foundation for the PENNSTAC project. Companies such as IBM and General Electric also chipped in for the project by offering various donations. Eric Walker, Dean of Engineering at the time, once told close friend and IBM CEO Thomas Watson about the team’s struggles in constructing a magnetic storage drum. A little while later, a gift arrived for the PENNSTAC team — a new storage drum from IBM.
Alumni such as Dr. William Adams, former head of the engineering computer lab, recall students being paid fifty cents each hour for their labor on the project. The design and building process alone would lead to the writing over sixty graduate theses.
Although PENNSTAC took more than two years to build, the creation was unlike anything if its time. PENNSTAC weighed more than 3,500 lbs. and took up a whooping 80 square feet, not including the space for the air conditioning system needed to keep the unit cool. Even with air conditioning, the unit could only run for a few hours at a time or else it would overheat.
But PENNSTAC wasn’t just impressive by physical size alone — according to a 1957 Daily Collegian article, PENNSTAC “can perform 1,400 additions of 10-digit numbers in one second, and its magnetic drum can store 2,500 10-digit figures” — a notable amount for its time.
Researchers in disciplines such as chemical engineering, agricultural economics, and meteorology used PENNSTAC. The system solved numerous problems and computations, as well helped farmers predict season yields for the School of Agriculture.
Like many inventions of its time, PENNSTAC did not last long before eventually becoming obsolete. The project was a valuable Penn State tool for research until 1968 when it retired to make room for a new commercially-built computer. Today, you can find PENNSTAC on campus by visiting its historical marker sign outside Electrical Engineering West.