Magnetic film storage units

The thin magnetic film has now become a very attractive addition to the ferrite toroid and plate matrix as storage and switching elements in digital computers. Five types of film unit are being investigated: Nickel-iron vacuum evaporated on insulating and conducting substrates. Nickel-iron electrochemically deposited on conducting substrates. Nickel-cobalt chemically deposited on insulating substrates. Nickel-iron deposited by cathodic sputtering on insulating substrates. Ferrite films on insulating substrates or self-supporting. Of these, the first has been the most extensively examined. The rest are alternatives attempted as possible improvements over the first type. Advantages offered by thin-film storage units are small size, small power required for switching and very high switching speeds. The main disadvantage is the small Output signal of the film, making the design of sensing amplifiers used in the computer circuit more critical.