The BYU coaches suspected it because the only plays that seemed to work at all were audibles. And UTEP was upset about overhearing BYU coaches talk about the AL and NL playoffs. Back then, I believe the calls were relayed from the press box to the field over a low-frequency FM channel so everyone was "on their honor" to stay off the other team's frequency. (Are the frequencies secure today?) Apparently the winless UTEP staff didn't have much honor. I can't find the report, so maybe it's just rumor or articles from 20 years ago aren't on the web. I remember something about a letter from the president of UTEP to President Holland. Bill Yung didn't coach again and went into insurance sales. It's been a long time, but I remember being very convinced that this happened.