Valley residents may have experienced problems with some of their favorite stations from about 7 a.m. to 8:30 a.m.
Phoenix police received a call at about 8:30 a.m. that someone had damaged some of the electrical panels at the antenna farm on South Mountain's summit, said Phoenix police spokesman Sergeant Vince Lewis.
Cops detained one person on suspicion of trespassing during their investigation of the incident, but haven't released the person's identity.
(UPDATE: Police later identified the suspect. See below.)
Stations affected included Channel 8 (KAET-TV), Channel 12 (KPNX-TV), and Channel 33 Univision (KTVW-TV), he said, plus stations managed by Hubbard Radio.
Hubbard owns several radio stations in the Phoenix market, including KUPD and KDKB. A message left with the company wasn't returned. Channel 12 also didn't return a message.
"Fortunately, I think it had minimal impact," said Mark Lodato, an assistant dean with Arizona State University's Walter Cronkite School of Journalism and Mass Communication, which runs Channel 8. "It's now in the hands of Phoenix police."
Viewers of Channel 8 who subscribe to Cox cable or other subscriber services weren't affected, he said.
A statement by KAET released on Wednesday said a portion of Channel 8's viewing audience experienced an outage from about 7 a.m. to 8 a.m.
"Our broadcast engineering team worked quickly to resolve the situation and get Arizona PBS back on the air," the station reported.
The 42 antennas on the summit of South Mountain broadcast most of the area's TV and radio signals. They're among the most prominent landmarks in metro Phoenix; their glowing red lights can be seen at night from almost anywhere in the Valley.
UPDATE: Sergeant Lewis sent a release late Wednesday night naming the suspect as Micheal Preston, 41.
Preston was found by police "inside the fenced area where No Trespassing signs are posted. He was detained," Lewis said in his statement. "Inside the fenced area, where several broadcast radio and television transmitters are located, several power junction boxes and other equipment had been manually shut off or damaged causing several radio and television stations to experience outages or service interruptions. Preston was booked into jail on one count each of commercial burglary, criminal damage and trespassing."
UPDATE 2: Preston, who is homeless, was released on his own recognizance at 2 a.m. Thursday by Maricopa County Court Commissioner Sigmund Popko, records show.
Preston promised to appear for court hearings on March 2 and March 8. He will be assigned a court-ordered attorney.
Officers found six individual tower facilities that Preston had tampered with, court records state:
* The tower for KUPD, KSLX, KDKB, KAZG, and KDUS had seven power boxes damaged, which shut off power to the stations and cut off their signals.
* The tower to Channel 3 (KTVK-TV) and Channel 5 (KPHO-TV) had the power shut off, but no damage.
* The tower to KHZZ, SPOT, and KBACH had the power shut off but no damage.
* The tower to Univision had the power shut off, interrupting service to Tucson.
* The Tower to "I Heart Media" had the power box damaged, shutting off the power to the tower and cutting off the broadcast.
* The tower to Channel 12 (KPNX) and PBS had three power boxes shut off and one power box damaged, cutting power to the tower.