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News Highlights

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IBM scientists generate worlds shortest pulses

IBM scientists at Yorktown Heights have madę and measured the world*s shortest pulses, an important step in de-signing the ultrafast electronic Computer components of the futurę.

Using a laser and a very fast switch, the scientists produced electrical pulses lasting only one half of a picosecond (one trillionth of a second). Until this experiment, researchers had never broken the “picosecond barrier” with an electrical device.

Today’s fastest experimental Silicon logie devices can switch on and off in about 30 picoseconds; gallium arsenide devices in about 10 picoseconds. But to investigate the electrical behaviour of these devices, researchers must be able to measure pulses at least 10 times faster than these switching times.

The techniąue used to make the half-picosecond pulses can measure electrical pulses up to 20 times briefer than the switching times of the fastest present-day devices. As a result, IBM scientists will be better able to understand how electricity travels through Computer components — transistors, chip connec-tions and transmission lines.

To generate the pulses, IBM researchers fabricated a transmission linę on a thin Silicon layer. The transmission linę consists of two parallel one-micron-wide aluminium strips two microns apart. During operation, a voltage is maintained across the aluminium lines.

A pulsed laser beam, consisting of a series of sub-picosecond light pulses, is split into two beams by a minor. Be-

Canberra FM station chooses Audiosound monitor speakers

Audiosound Laboratories recently supplied their latest 8045A Control monitors for the new 2CA studio in Canberra. They are to be used for the new FM station and the satellite service of Macquarie Broadcasting in Canberra.

The 8045A is a upgrade of Audio-sounds’ previous model the 8045, al-ready used by 2CA, 2GB and the ABC. The 8045A features a new vented magnet woofer, high temperaturę voicecoil and restyled all-timber veneered cabi-net. •

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cause the beams follow different paths it is possible to delay one light pulse stream.

The first light pulse strikes the Silicon between the two aluminium lines, short-ing them for a fraction of a picosecond and creating an electrical pulse that travels down the transmission linę. The electrical pulse is an ultrashortchange in the voltage that moves down the linę.

As the electrical pulse travels down the linę it passes a very fast optical switch, which samples it.

The second light pulse, time-delayed slightly by the longer optical path, drives the sampling switch, measuring the electrical pulse as it flies by. Researchers measure the time delay neces-sary to collect the electrical signal to determine the duration of the pulse.

Industry Briefs

•    Australian industrial robot designer and manufacturer Machinę Dynamics has been commissioned by the Ford Motor Company of Australia to supply two robot assembly Systems. The contract is worth morę than $5 million, and involves the design, manufacture and installation of 22 gantry robots with auxiliary gripping. tooling and positioning devices.

•    Dr Peter Crawford, former chief executive of the Sydney Water Board. has been appointed the new managing director of Amalgamated Wireless (Australasia). Former AWA chief scientist Dr Lou Davies has also been appointed to the board. to replace Mr E.B.Gosse. who has retired.

•    Local printed Circuit board maker Printronlcs has had its 18-layer PCBs tested independently by two overseas NATO contractors. who found them to meet both MIL-55110D and the even morę stringent BS 9000 quality standards. Printronics recently installed the Multiline registration system for multilayer PCBs. which produces tolerances previously thouaht unachievable.

•    Hobart-based antenna manufacturer Moonraker Australia has won contracts

worth about $500,000 to supply frequency agile HF antenna Systems to Codan, Australia's largest HF transceiver company. Moonraker has also won a contract i worth morę than $50,000 to supply marinę radio antennas to the Australian Navy.    I

• Australian manufacturer STC has been awarded a three-year $A50 million    i contract to supply PCM, digital multiplex and fibrę optic telephone exchange equipment to the New Zealand Telecom Corporation. STC chairman Bill Page-Hamfy says this is the largest contract for transmission equipment awarded

to an Australian Communications company for many years. For many years NZ s has purchased this type of equipment from Japan.    .

•    Crusader Electronic Components has been appointed Australian and New Zealand distributor for ITT Semiconductor's chips and SMD produets. According to Crusader’s managing director Des Connors this now gives his company a complete rangę of active and passive components for local manufacturers.

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ELECTRONICS Australia. September 1987