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Magnetic Tape Storage

Eckert-Mauchly Computer Corporation

Magnetic tape storage has not always been used for computing, it originally started as a means for audio recording in 1928. Years later, 1951 to be exact, it was developed by the Eckert-Mauchly Computer Corporation to record digital data, not just sound. The first magnetic tape for computers was the UNISERVO 1 to be used as an input and output receiver for the UNIVAC 1 in 1951. This was meant to replace the paper punch cards being used for input on computing machines as they are not very sturdy and quite susceptible to damage. About one year after the UNISERVO 1 was released, IBM began to use magnetic tape for data storage as a device called Model 726. IBM’s product was the first commercially available magnetic tape digital storage device. The original tapes could hold 1.1 MB on a single tape, while today they can hold up to 15 terabytes; that is more than a 13 million percent increase in capacity.
The tape was made from a phosphor-bronze material with the same mechanisms as what has been used in the past. The sections of tape are either charged or not create the binary 1s and 0s that we are accustomed to in computing. The tape held about 128 bits per inch that were run along a pulley type system in order to be read. This is quite a lot considering each reel had about 1200 feet of tape encased. The individual reels were actually quite heavy (about 25 pounds) considering the size and material; for comparison, the entire UNISERVO 1 machine was about the height of an adult male.
The nature of these products did not allow them to just be bought and sold to the public, but rather IBM rented their external storage device with the computers. The Model 726 on its own was rented by the company for $850 per month. Today, that would be a little over $8,915, which was definitely not affordable for the average consumer.

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