Early Development in Solid State Devices
Early Electronics Research - Velvet Glove - Transistors
Early Electronics Research/ Velvet Glove
At the new Electronics Laboratory, the first task was a thorough study of Service needs in the field of electronics research to determine important requirements which were common to more than one Service. This study, conducted under the guidance of Mr. J.W. Cox, concluded that one of the most important tri-service requirements was the development of a multiple-channel, multi-frequency communication system capable of operating at ranges of up to 200 miles and, which would be smaller, simpler and lighter than the ones already in existence. Accordingly, work was begun on this project and the progress made during 1950 and 1951 was satisfactory, but in 1951 the Defence Research Board undertook the development of the "Velvet Glove" guided missile and the main emphasis at the Electronics Laboratory had to be shifted to support this program. Dr. Irvine Paghis was placed in charge of the team of scientists at the Electronics Laboratory who were developing the warhead fuse for "Velvet Glove"; and for the next four years the largest scientific team in DRTE was exclusively devoted to supporting the guided missile project. The fuse development was successful and by the time the "Velvet Glove" program was turned over to industry, an industrial team from Canadian Westinghouse had been trained at the Electronics Laboratory to continue the work.
Apart from the development of the electronic systems for "Velvet Glove", the scientists at the Electronics Laboratory were concerned with research on radar, navigational aids, and general electronics. Some of these projects, such as the work on electronic counter measures and on detection systems against aircraft and ballistic missile threat were of a secret nature.
Studies were related to methods of interception, jamming, or deflection. In addition to this secret work, the Electronics Laboratory was also concerned with the development and improvement of more conventional electronic systems used in defence.
Considerable research was done on transistors, those tiny electronic devices which rapidly replaced the larger vacuum tubes in so much modern (for the time) electrical equipment, and on related solid state devices. This research into circuitry frequently involved entirely new mathematical and physical developments and, since it was a relatively new field, the prospects of improvement were virtually unlimited. At the time, it was believed that transistors would revolutionize the electronics industry. The size and weight of every type of electronic gear was being drastically reduced, while the operational uses to which electronics could be put was being altered and increased. Transistors promised higher reliability than vacuum tubes, which meant that more complicated electrical equipment could be developed without the risk of component failure. At the time, an Electronics Laboratory scientific team under Mr. N.F. Moody was continually studying and testing the many new transistors which were being produced, selecting those which promised the highest performance for military purposes, suggesting modifications and improvements to industry and re-designing radio circuits on Service equipment to take the fullest advantage of new development. Representatives from Canadian industry attended instructional courses at the Electronics Laboratory in transistor techniques and the uses of transistors in general, so that DRB knowledge could be shared with Canadian firms who manufacture Service electronic equipment. Related to this transistor program is the broader task of reducing the weight of electrical equipment by means of new, lightweight material and other techniques.
Field Effect Transistor Amplifier
About the middle of 1973, a U.S. company ran into problems with the 12 GHz Transferred Electron Amplifier, which the company was building for inclusion in the payload of Communications Technology Satellite (Hermes). CRC microwave specialists were asked to look at the problem and agreed with the manufacturer that it was unlikely that the difficulties could be overcome quickly. As a result, the decision was made to use a Field Effect Transistor Amplifier instead. A field effect transistor amplifier is a solid state device used to obtain amplification at microwave frequencies. It first became available in the early 1970s. This case history refers to the first use made of a field effect transistor amplifier in a spacecraft. After this time, field effect transistor amplifier devices were used widely, not only in spacecraft, but also in the ground stations of space systems.
None of the U.S. companies active in the field were prepared to guarantee performance and schedule and to accept a fixed price contract. Since CRC had a better microstrip technology base and a greater microwave capability than existed elsewhere in Canada, it was agreed between RCA and CRC in October 1973 that the amplifier be built by CRC, with a May 1975 completion date. CRC attempted to integrate engineers from RCA Limited which was building the spacecraft transponder in the development work.
Fairchild was the only supplier of completely packaged devices. However, when a number were bought and tested it became clear that the company, at the time, could not measure the performance adequately. Meanwhile, Plessey in the United Kingdom, was willing to supply devices in chip form. Samples produced on a laboratory, rather than a production line basis, were made available by Plessey. CRC designed and produced the chip package. Work at CRC on the Fairchild device and on the Plessey device amplifiers continued in parallel. As Fairchild supplied a packaged device, progress with this was quicker and the first operational amplifier was available in April 1974. However, the narrower gate structure used by Plessey provided a better device and, although the device was not packaged, the amplifier design proceeded quickly. By the fall of 1974 the first engineering model using a Plessey device was followed by a qualification model using a Fairchild device. Eventually CRC produced engineering, qualification and protoflight amplifiers using Plessey devices and the same amplifiers with Fairchild devices. All this was done in eighteen months by a design team which totalled nineteen people at its peak, including two RF design engineers and three technicians, with good support in packaging and power supply design and in reliability analysis. This technical team could not have achieved such remarkable results without full administrative support and the help of the Department of Supply and Services in expediting requisitions.
Redundant Field Effect Transistor amplifiers, each using either the Plessey or the Fairchild device, were flown on Hermes. In its life in space of nearly four years, the Hermes satellite used only the Field Effect Transistor amplifiers with the Plessey device and no abnormalities in performance were reported.
No licensable or patentable technology was developed at CRC in the course of this development work. Generally, circuit techniques are not patentable, although a good deal of technological innovation was involved. For example, the use of kovar to design packaging capable of meeting the temperature specifications was highly innovative. Much was learned on RF design, including the design of butterfly bias networks, filtercons and the failure mechanisms which can lead to degraded reliability. All the knowledge which had been acquired at CRC was made available to RCA and contributed to the success the company had in designing field effect transistor amplifiers for use in the RCA Satcom (6/4 GHz) and the Anik B (6/4 GHz).
The use of field effect transistor amplifiers in the construction of RCA Satcom and the Anik B satellite. Another spin-off occurred in 1975, when a contract was rewarded to SED Systems Limited to establish itself as a supplier of microwave components for earth stations to be used in satellite communication systems. As a result, SED built 4 and 12 GHz low noise amplifiers using field effect transistor amplifiers. In the course of this development, CRC personnel spent time at SED and SED engineers made visits to CRC to make use of the knowledge acquired in the design of the field effect transistor amplifiers for Hermes.
Goodspeed, Captain D.J. A History of The Defence Research Board of Canada. Ottawa; Queen's Printer, 1958.
Bhaneja, B., Lyrette, J., Davies, T.W. and Dohoo, R.M. "Technology Transfer by Department of Communications: A Study of Eight Innovations." MOSST Background Paper. Ottawa; Supply and Services, 1980.