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Very possibly, but the EMI-Marconi system was the first fully electronic television system to be used in regular broadcasting, which is to say that it was the first practical system.
Earlier systems may have been practicable, but they weren't used in practice.
I worked at EMI Central Research for a couple of years, and even got to talk to William S. Percival for a while, so I may be prejudiced.
-- Bill Sloman, Nijmegen