A cathode ray oscilloscope is essentially an electronic display device containing a cathode ray tube. It produces visible patterns that are the graphical representations of electrical signals. The graphs plot the relationships between two or more variables, with the horizontal x-axis normally being a function of time (sweep generator), and the y-axis (vertical amplifier) usually a function of the voltage generated by the input signal to the oscilloscope. Because almost any physical phenomenon can be converted into a corresponding electric voltage, the oscilloscope is a versatile tool applicable to most forms of physical investigation.

This unit is a differential type, permitting the pick-up of small signals in the presence of large interfering signals, which swamped the small signals in previous non-differentiating models. It also uses a sweep generation system, permitting very superior registering of infrequent pulses or widely spaced signals.

This unit is historically significant as it was one of the very first of its type to be manufactured. It was also one of the first of its type to be used in Australia. It was used as a general purpose recording oscilloscope in the Electronics Department at Macquarie University.

This unit makes an excellent addition to the Museum's small collection of older model oscilloscopes.

Manufactured by Tektronix Pty Ltd between 1963 and 1969. Tektronix is a United States corporation best known for its test and measurement equipment such as oscilloscopes, logic analysers, and video and mobile test protocol equipment. The company traces its roots to the electronics revolution that immediately followed World War II. The company's founders, C. Howard Vollum and Jack Murdock, invented the world's first triggered oscilloscope in 1946, a significant technological breakthrough.

Tektronix in Australia became NewTek Sales Pty Ltd in December 2001. NewTek no longer exists. The current representative of Tektronix in Australia is TekMark Australia Pty Ltd.

Purchased by the Electronics Department at Macquarie University. It was used as a general purpose recording oscilloscope before being donated by Macquarie University to Tektronix for its museum collection. The company in turn donated the unit to the Powerhouse Museum.

Oscilloscope, dual beam differential cathode ray, Type 502A, metal / plastic / glass / perspex, made by Tektronix Guernsey Ltd, Channel Islands, 1963-1969, used by Macquarie University, Sydney, New South Wales, Australia, [1967-1970]

An oscilloscope (sometimes abbreviated CRO, for cathode-ray oscilloscope, or commonly just scope or O-scope) is a piece of electronic test equipment that allows signal voltages to be viewed, usually as a two-dimensional graph of one or more electrical potential differences (vertical axis) plotted as a function of time or of some other voltage (horizontal axis). The complete apparatus comprises a cathode ray tube, which forms the measuring and indicating portion of the instrument, and a number of subsidiary units or circuits for providing suitable power supplies, for amplifying or attenuating the voltage to be measured, and for ensuring that the instantaneous values of that voltage are displayed on the screen in succession so that the trace takes the form of a graph in which the voltage is plotted against time.

Type 502A was introduced in 1963 by Tektronix Australia Pty Ltd. The unit has a maximum band width of 1 MHz, dual differential channels, X-Y curve tracing with one or two beams, single sweep operation, and plotting frequency of 100 kHz. It is a differential type, permitting the pick-up of small signals in the presence of large interfering signals, which would have swamped small signals in previous non-differential types. It uses a sweep generation system, permitting very superior registering of infrequent pulses or widely spaced signals. This oscilloscope has an operating range of 210-280 volts and 50-60 cycles.

Tektronix replaced the metal casing of this unit with perspex to reveal its electrical components.

Made: Tektronix Incorporated; United States of America; 1963 - 1969

Used: Macquarie University; Sydney, New South Wales; 1967 - 1970

Used: Tektronix Incorporated; Sydney, New South Wales; 1970 - 2007

'Serial 104092' inscribed on front, upper left corner. Manufacturer and logo inscribed on front, lower right corner.

2007/192/1

1963 - 1969

390 mm

596 mm

290 mm