Elkus spent the first decade of his career at Ampex Corporation. As manager of the Educational and Industrial Products Division he wrote the original product plan for the home video recorder and headed the team that introduced the VCR to the world in 1970.
He served as chief executive and on the board of several high-tech companies: including Executive Vice President and General Manager of Geometrics, Inc., Director and Chairman of Pacific Measurements and Integrated Systems, Inc., Co-Founder, Chairman and CEO of Prometrix Corporation, Director and Vice Chairman of Tencor Instruments, Director of KLA-Tencor, Director of OnTrak Systems and Director of Lam Research, In addition he served as a Director of Tomex Corporation, Virage Logic, SOPRA-SA, and Cameca-France.
His professional affiliations, past and present, include serving as Chairman of the Selection Committee of the National Science & Technology Medals Foundation, member of the Board of Directors and executive committee of the National Science and Technology Medals foundation, member of the Board of the American Electronics Association, member of the Board of trustees for The Scripps Research Institute, member of the Board of Trustees of the Palo Alto Medical Foundation, member of the University of California (UC) President’s Board on Science and Innovation, and Board of Trustees UC Merced Foundation, Chairman of the National Science Foundation Panel on High-Definition Products and Systems, Co-Chairman of the American Electronics Association Committee on High-Definition Television, Vice Chairman of Government Policies Committee of the Defense Science Board and member of the Board of International Counselors for the Center for Strategic and International Studies.