Growing up, I read every Martin Gardner science book that I could lay my hands on. Janet even claims that I ignored her on our honeymoon in order to read Gardner’s Relativity for the Million (which is absolutely not true—it was The Ambidextrous Universe). Gardner was a colleague and friend of Asimov’s, which led to a series of sf puzzle stories beginning in the first issue of IASFM and continuing through November of 1986. There was a mention of tachyons in the Mar/Apr 1978 puzzle (“The Third Dr. Moreau”), and the May 1979 puzzle (“How Bagson Bagged a Board Game”) had a device to view the past, but the first actual time travel didn’t occur until February of 1980, quickly followed by another in July 1980 (which coincidentally was the month of the disputed honeymoon).
Somewhere in the text is a block of letters which taken forward spell the last name of a top science fiction author who has written about time travel.

Variants

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  1. Martin Gardner’s SF Puzzles by Martin Gardner, Asimov’s Science Fiction, February 1980.
    2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by Martin Gardner