In 1963 he co-founded the medical instruments company Telectronics Pty Ltd in Sydney, and served as the company's Chief Engineer from 1963 to 1970 and Technical Director from 1963 to 1978. He was elected an Honorary Life Governor of Royal Prince Alfred Hospital, Sydney in 1982, and was appointed Officer Of The Order Of Australia in June 2000 "for service to the design of medical equipment, particularly in the development of the implantable cardiac pacemaker".
His accomplishments are remarkable in that he had no formal engineering training, finishing High School at year 8 to commence work as a radio and electrical repairman. At age 21 he passed the year 12 examinations by night study at the Adelaide School of Mines, while working as a senior technician at the Department of Supply Long Range Weapons Establishment in South Australia, and being appointed the same year on merit as an electrical engineer at graduate level by the Netherlands Philips company subsidiary T.C.A. Pty.Ltd.
In 1958-9 he studied application of the new technology of the transistor at Philips establishments in the Netherlands and England; being relocated after that to Philips' Sydney headquarters.
In 1964, after being co-founder of Telectronics Pty. Ltd. in 1963, the company was invited to participate in artificial cardiac pacemaker research in which co-founder and initial financier Noel Gray and he as head of research and development made significant contributions. His involvement as a director of Telectronics ceased in about 1982 when control of the company was gained by Nucleus Limited.
Subsequently, while continuing involvement in bio-engineering particularly in paediatrics, he studied aerodynamics and structural engineering, which led to construction of a fuel efficient light aircraft which was awarded the SAAA prize of the "Henry Millicer Best Australian Technical Innovation and Design" in 1998.
He was the recipient of the Institute of Engineers, Engineers Australia, 2007 "David Dewhurst Award " "In recognition of his outstanding contribution to the profession of Biomedical Engineering".
At age 77, he was the lead co-researcher of a team at Sydney's The Children's Hospital at Westmead developing and clinically trialling a new form of therapy for a childhood condition, funded by a A$330,000 Grant by the National Health and Medical Research Council.
He is the father of four children and has nine grandchildren (at January 2011)
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- Wickham, Geoffrey (1976-10-05). "Muscle stimulator". United States Patent 3983881. U.S. Patent Office. Retrieved 2006-11-11.
- Wickham, Geoffrey (1976-10-12). "Demand heart pacer with improved interference discrimination". United States Patent 3985142. U.S. Patent Office. Retrieved 2006-11-11.
- "Search Australian Honours". It's an Honour. Australian Government. Retrieved 2006-11-11.