WSJ sees issue with AM HD interference
Well, we've certainly brought up the problem (6/9/04 RBR #112).
Now The Wall Street Journal sees it as an issue, too (excerpts from a 3/2 story):
"Digital Signals Spark Static From AM Radio; Bill Harms of Elkridge, Md., likes to listen to Frank Sinatra crooning on Vegas Radio, which broadcasts at WTRI-AM 1520, a Washington-based station. But over the past year, he's had trouble tuning in to Vegas as he drives through certain neighborhoods. As he complained to WTRI owner Buddy Rizer in an email, ''there's a hiss, a hiss that did not exist in the past.''
A growing number of radio listeners are encountering similar interference -- hisses, whistles or static -- on their favorite AM stations. The problem for WTRI began about a year ago, when Bonneville International Corp.'s WTOP, the AM station at 1500, began using a digital signal that interfered with WTRI's analog signal in some broadcast areas. It's one of the unexpected consequences of the radio industry's transition to digital broadcasts.
Big radio companies, such as Clear Channel Communications Inc. and CBS Corp.'s CBS Radio, have raced to embrace digital broadcasting, adding digital signals and rolling out new programming. But that has left behind many smaller AM stations that are still broadcasting only an analog signal. They are experiencing so-called side-channel interference -- a phenomenon brought on in part by the fact that AM stations are packed tightly onto the dial, with only 10 kilohertz separating each one.
The AM stations most affected are those whose neighboring stations - - nearby on the dial - - add a digital signal. In most cases, including Mr. Rizer's, the interference doesn't stretch into a station's core coverage area, as defined in its Federal Communications Commission license. But in fringe areas, signals can be fuzzy, or lost entirely.
The problem for stations like WAGS and WTRI is likely to expand before there's any resolution. As of the end of 2005, there were 4,757 AM stations and 8,903 FM stations in the U.S.; 700 had added a digital signal. (Stations don't substitute digital for analog signals, because most listeners still have only analog radios.) That number will grow as more listeners buy digital radios, and more stations broadcast to them. Radio engineers hope to find new technologies that will assist small AM stations, but there isn't much yet.
For some small AM operators, it adds insult to injury that the only company licensing the digital broadcast technology is one backed by the small stations' deep-pocketed competitors: Ibiquity Digital Corp., based in Columbia, Md., is the only company selling the "in-band, on-channel," or IBOC, technology, that allows digital signals to be broadcast alongside analog signals. Investors in Ibiquity, a closely held company, include most of the major radio companies, including CBS and Clear Channel, as well as automotive companies such as Ford Motor Co., communications equipment makers such as Harris Corp., and venture capital and private-equity firms such as J.P. Morgan Chase & Co.'s J.P. Morgan Partners.
Still, many small AM operators worry that Washington might someday mandate a switch-off of analog to create more room on the radio spectrum or to simplify the transmission of digital signals. The financial pressure would, "in effect, squash the small station,'' says Mr. Jenkins, who runs the bluegrass station
Mr. Rizer and his partner, Martin Sheehan, didn't anticipate the digital problem when they bought WTRI, a former Korean-language station, in 2004. They quickly built a fan base in Washington's western suburbs. While the signal remains clear in WTRI's core coverage area, it's now harder to pick up in towns like Potomac or Rockville, Md. For the moment, Mr. Rizer has resigned himself to focusing on his core area around Brunswick, broadcasting on the Internet, and hoping to upgrade to digital himself one day."
Good Morning - Gain a personal edge on today's business day. Are you reading this from a forwarded email?
