You can see another example of Summitone here.

     This XAM is a fabulous performer. It pulls in distant stations with ease, clarity, and it is LOUD.  Who would think of a name like XAM?

     In electronic tech circles, "x" is shorthand for "trans," as in "xistor."  How about shorthand for "Transam?" Or "Transistor AM?"  Kind of punny, huh?

     Some Japanese radios went through an American-sounding naming phase, coming up with  names such as Sportster, Americana, Trans-America, Hudson, Playmate, and even GM. (Credit to Michael Brian Shiffer, from his book "The Portable Radio in American Life," The University of Arizona Press, 1991.)