Thursday, September 2, 2010

Among AM HD Users, Opinions Vary

Among AM HD Users, Opinions Vary
by Randy J. Stine, 09.02.2010

The experiences of broadcast engineers managing AM HD Radio signals appear to vary greatly.


Noncommercial WKAR(AM) in East Lansing, Mich., launched HD Radio in 2005 but turned off the digital carrier in 2009, according to Harold Beer, chief engineer for WKAR, which is licensed to Michigan State University.

“After years of encouraging listeners to get better quality wideband AM radios, we ended up degrading their listening experience with a 5 kHz bandwidth, –35 dB SNR analog signal once we turned on the IBOC digital,” Beer said.

“We also collected a number of negative comments due to the digital carrier, including complaints about the buzz that was always present, especially if a listener had an analog tuned radio that was slightly off-channel.” WKAR is a daytime directional AM operating on 870 kHz with 10 kW.