XETRA

"The Mighty 690" was a 50,000-watt, border blaster Top-40 station licensed to Tijuana, Baja California circa the early 1980s.  Even though it was based in Mexico, its huge signal allowed it to cover not only San Diego but all of Los Angeles as well.
A former XETRA intern runs an online tribute to "The Mighty 690" which can be found here.