LOS ANGELES — The correspondents were on camera and on location in Mexico City, Washington, and Los Angeles. Rolando Nichols, the lead anchor, listened intently to the microphone in his ear as he stood in front of the bright red walls of the news studio.

But the news would have to wait: Engineers and producers in the control room were having trouble with the sound.

Fortunately, this was not a live news broadcast. It was a test run for MundoFox, the newest Spanish-language network in the United States.

On Monday, the network — a partnership between Fox International Channels, owned by News Corp., and RCN Television in Colombia — will debut in 50 cities, including Boston, Chicago, Houston, Los Angeles, Miami, and New York.

MundoFox will be entering a market long dominated by Univision and the smaller Telemundo as it tries to gain the attention of the millions of Latinos who watch Spanish-language programming. The effort is estimated to cost $50 million.

By the end of the year, network executives expect to be in 60 cities, reaching nearly 80 percent of Latino audiences in the United States. It is the first time RCN will be part owner of a broadcast network in the United States.

‘‘We aren’t anyone yet, even though we have an exceptional product,’’ Jorge Mettey, the network’s senior vice president for news, said in Spanish.

A few miles away, at Fox Studios, Emiliano Saccone, president of MundoFox, explained the network’s philosophy.

‘‘Right now we are as American as anyone else, and we have the political and financial power to essentially step up,’’ he said of Latinos in the United States. ‘‘It’s no longer about defending ourselves from perceptions or beliefs as much as it is about looking forward.’’

To that end, the network’s tagline will be ‘‘Americano Como Tu,’’ or ‘‘American Like You.’’