Yes he was, I remember my father watching his shows on TV in the 50's. I was daddy's boy and would watch bits and peices of the shows.
(Interesting theme song he had on the TV series, in fact I just heard it this week on a classical radio station, I believe it is titled "Funeral March of the Marionettes", fitting for Hitchcock.)
I loved his shadow on the wall in the "Psycho" remake. That was classy of that director to do that.