АҚШ-қа қуатты радиосигнал тарататын XERF станциясының тарихы

IMER radio station in Ciudad Acuña, Coahuila

Prior to , XERF retained the Wilson and Howard Radio Advertising Agency to handle its United States ad sales. In that year, Bósquez and González formed a Texas corporation called Inter American Radio Advertising, Inc. which was located on Pecan Street in Del Rio, Texas. While XERF's concession remained with Compañía Radiodifusora de Coahuila, the actual control of the airtime and the management of the facilities in Ciudad Acuña were under the control of Inter American Radio Advertising. The Texas company purchased a 250000 RCA transmitter to broadcast an omni directional clear channel signal on AM 1570, which originated some distance from the old XERA facilities within three new prefabricated concrete buildings with flat roofs. The sales brochure for XERF offered this explanation about the operation of the station (emphasis and wording shown as in the original text):
There is, of course, one BIG difference between U. S. and Mexican Stations, and that is a matter of POWER; American Stations are limited a maximum 50000 a limitation that does not exist under Mexican regulation. X. E. R. F. for example, is licensed to operate on 250000 power, and the Department of Communication and Public Works of the Mexican Government has authorized a power increase to 500000. Such power could result in serious interference if wave lengths were not strictly maintained, but the equipment with which X. E. R. F., operates assures its signal to stay "right on the beam." This is something constantly checked by FCC monitor stations, a degree of regulation by the U. S. Government alike that is imposed upon U. S. Stations. Operating on a clear channel, X. E. R. F. is heard nightly in all parts of the fifty States in the United States, Canada and Latin America. Although reference was made to a power increase, the station only had an RCA 250000 transmitter.

The booming bass voice of Paul Kallinger was used to sell many of the products on XERF. At night, his recorded spots between the different sponsored shows served as a jingle break. Kallinger remained on the Texas side of the border and recorded his spots at a studio in Del Rio, because he did not want to become embroiled with the lawlessness that swirled around the XERF studio and transmitter on the other side of the border. In between the different religious programs, Kallinger would tell XERF listeners in various versions that:

It’s always good to know that we have some fine people out there listening to the most powerful commercial voice in the world From alongside the beautiful Rio Grande, this is XERF, Ciudad Acuña, Coahuila, Mexico. Our mailing address is Del Rio, Texas. This is Paul Kallinger. As Mexican law required stations to identify in Spanish, the portion identifying the station's call letters and the station's location in Mexico, was then repeated in that language. Kallinger, along with fellow XERF alumni Bill Mack, were inducted into the Texas Country Music Disc Jockey Hall of Fame in in recognition of their influence on the development of country music. Mexican authorities intervened, stationing federal troops to guard the station. In testimony, employees said they were chased, and that one armed man threatened Kallinger with a .45 pistol. After a legal dispute, a judge found in favor of Saúl Montes, the station's administrator, who put the station back on the air. In , a gun battle at the station left a 50 year old man dead; his body was found on an adjoining ranch. Station personnel broadcast panicked pleas for help, prompting local residents to notify the authorities. After the second gun battle, Bob Smith decided to leave for XERB, a border blaster in Tijuana and listenable in Los Angeles, California. It was this station that George Lucas featured in the movie American Graffiti. Meanwhile, XERF reverted to selling time according to the old format devised by Dr. Brinkley. It featured paid programming, most of it from American fringe evangelists, right wing political groups and Black Nationalist messages from the Nation of Islam. In , a pastor sued the station for removing him from its air, alleging that the contract he had signed was for the duration of its broadcast concession. In the early , the station faced another lawsuit over contracts for airtime on XERF. In early , station employees who had been seeking back wages for 13 years, since the gunfight, won a victory in Mexican court, and Montes was appointed the sole administrator of XERF. With the advent of FM stereo radio broadcasting, interest in the static prone mono AM signals of XERF began to wane and its signal was switched from the 250 RCA transmitter, which was never paid for and which consistently kept breaking down, to a new 50 transmitter. Its program schedule consisted of primarily religious shows, and it did not broadcast during the day.

In , Bob Smith (Wolfman Jack) ran into a radio engineer friend named Mike Venditti, and he told Venditti that no one had been able to get XERF back on full power with its old RCA 250000 transmitter, because RCA did not have any manuals relating to the equipment. Venditti then approached González with a business proposition.

In exchange for restoring the main RCA transmitter to active duty, Venditti asked González to lease him the daytime hours from to Because the station was only operating on a fraction of power from the 50000 transmitter, XERF was not on the air during the day.

However, one Mexican group was highly interested in taking control of XERF for itself. In , the federal government created the Instituto Mexicano de la Radio (IMER, lang es), which initially owned all of the radio stations which the government had come into owning through other agencies. Given XERF's geographic location, transmitter power, and status on a clear channel, the Mexican government considered XERF of strategic importance to acquire. On , IMER purchased the assets of Compañía Radiodifusora de Coahuila, S. A. and immediately took over operations of XERF. Five days later, in a special shareholders' meeting, Compañía Radiodifusora de Coahuila voted to dissolve itself. The concession was formally transferred to IMER on However, once IMER acquired XERF, it was left with the old, broken transmitter, for which there were no parts, and a second, 50000 transmitter, which was also having problems, and XERF operated with only 15000. In , IMER began a modernization project nationwide. Special attention was paid to XERF, where IMER launched "Proyecto Ciudad Acuña" to improve the station's technical facilities and strengthen its vision for XERF. With the acquisition of a new transmitter, XERF raised its power to 100000 in On , President Vicente Fox formally dedicated XERF's new facilities. The goal of XERF under IMER is to provide a broadcast service that links migrating Mexicans to their original communities.

XHRF began broadcasts in HD Radio on October 28, 2012. The HD2 stream relays XHOF FM Reactor, while HD3 features XHIMER FM Opus, both IMER stations in Mexico City.