Hubbard Radio’s “The Gamut” WWFD Frederick, MD (820) has become a real-world laboratory for digital radio. It became the first AM station to go all-digital two years ago and then late last year it moved to begin testing multichannel broadcasting for digital AM. Now Hubbard has asked the Federal Communications Commission to extend its experimental authorization, permitting WWFD to conduct more testing of all-digital AM – even as an Indiana station is also becoming a radio laboratory.

“WWFD’s all-digital experiments over the past two years have sparked widespread positive interest in the radio industry,” said Hubbard in a request filed with the FCC this week. Based in part on the “groundbreaking” engineering experiments that have been conducted at the station, Hubbard said other broadcasters have sought the ability to also power down their analog signals and offer only a digital on-air product.

Xperi, which licenses HD Radio technology to broadcasters, still has plenty of things that it wants to use WWFD as a real-world laboratory for in order to improve digital radio. The company told the FCC that it would like to continue using the station to expand the testing of an HD2 multicast audio service for AM stations, the addition of different data services, testing new emergency alert services, and examining the performance of digital radio versus analog radio in a variety of all-electric vehicles. Xperi also has several engineering tweaks on its list of projects, including testing different audio bitrate sizes and audio formats, reducing the power level of the unmodulated pilot carrier level, and various moves to help improve building penetration.

Hubbard said that if its experimental authorization is extended for another year, it plans to continue testing various digital radio equipment, methods, and techniques, and conduct signal coverage assessments as it works with the National Association of Broadcasters’ PILOT program, Xperi, Kintronic Laboratories, and the engineering firm Cavell, Mertz & Associates.

WWFD has been operating as a digital-only AM station since July 2018 under experimental authority granted by the FCC. The blow to analog listeners has been softened by the continued simulcast of the AM on the Frederick, MD-licensed translator W232DG at 94.3 FM. Hubbard said if it is granted more testing time it plans to continue providing that simulcast so listeners without a digital radio can hear “The Gamut” programming. Yet through the continued testing, Hubbard said that WWFD would also help assess the “increasing potential” for the public to receive all digital AM transmissions with commercially available receivers already in use.

New Digital AM Test In Indy

Even as Hubbard Radio looks to keep its Maryland test of digital radio up and running for another year, the FCC has approved another test. The Media Bureau has green-lighted a request filed by Urban One gospel “AM 1310 The Light” WTLC Indianapolis to turn off its analog station and offer engineers another real-world site to determine the feasibility of all-digital AM, along with emerging multicast channel programming for digital AMs.

Audio Division Senior Deputy Chief James Bradshaw said in the decision that the test “is not likely to cause interference to any other station” and that “the public interest would be served by the knowledge gained through further testing” of digital radio. There was one small catch. “At this point, we are not authorizing the rebroadcast of the (second) multicast channel on an FM translator station,” Bradshaw said.

Urban One’s “The Light” format will not go dark for listeners who only have an analog receiver. That’s because the station is also relayed on a pair of FM translators – the Indianapolis-licensed W224DI at 92.7 FM and the Frankfort, IN-licensed W236CR at 95.1 FM. Urban One says W224DI puts a 60dBu signal over 78% of the market’s population and W236CR covers 69%, meaning the risk of losing listeners is low for the company.

Meanwhile, another request for an all-digital AM remains pending. Fort Wayne, IN owner Brian Walsh has petitioned the FCC in May to allow him to power down his analog transmitter and operate WIOE (1450) using only a digital signal for the next year. Like most of the other test sites, WIOE has a translator –the Ft. Wayne-licensed W282CH at 104.3 FM – which would keep the station on the analog dial if the plan is approved.

Nine all-digital AM tests were previously conducted between 2012 and 2014, spanning a variety of station types and geographic locations prior to the WWFD test. Based on what have so far been positive reviews from many broadcasters, primarily those operating in smaller markets, the Commission voted last November to open a formal rulemaking (MB Docket No. 19-311) on the all-digital AM proposal. The idea has the backing of the National Association of Broadcasters. But some of the largest radio groups have said digital receiver penetration remains too low and it could further hurt AM’s long-term future with consumers and carmakers.

Xperi said more than 70 million digital receivers have shipped since the first units became available in 2005. The vast majority – 60.9 million – are installed in vehicles. Xperi also reported that as of Feb. 1 there are more than 2,500 digital radio stations nationwide, with fewer than 250 AM stations operating in hybrid mode.