POWERHOUSE COLLECTION

Sectioned cathode ray oscilloscope

Object No. 2007/192/1

German physicist Ferdinand Braun invented the cathode-ray oscilloscope (CRO) in 1897, and this one was made in Guernsey in the 1960s. Inside it, cathode rays (electron beams) move from the back of a vacuum tube towards the front, where they light up a phosphorescent screen. The variable of interest in an experiment is converted to a stream of electric voltages, which deflect the electron beam to trace a graph as different parts of the screen light up. The CRO is a very versatile, fast-response recording device. Debbie Rudder 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.