Wikipedia
XER-AM
XER (1932–1933) are the call letters of a famous border-blaster radio station licensed to Villa Acuña, Coahuila, Mexico, upon license application of Dr. John R. Brinkley of the U.S. state of Kansas. It first came on the air in 1932. It was forcibly shut down by the Mexican authorities in 1933 and the Villa Acuña Broadcasting Company was dissolved.