Most Popular Articles
NRSC Endorses AM IBOC for Daytime Only
Washington, DC - Mar 21, 2002 - The NRSC's AM IBOC working group will potentially recommend to the FCC that Ibiquity's AM IBOC is suitable for use during daytime hours only. The committee's results show that AM IBOC during the day yields performance comparable to that of FM IBOC. Nighttime operation of the AM IBOC system has outstanding issues due to first- and second-adjacent channel problems. Ibiquity has already stated that it does not expect AM IBOC to work via sky wave signals because of the three subcarriers that occupy the 15kHz mask. This means that AM IBOC will rely solely on ground wave propagation.
With ground wave coverage, the AM IBOC system provides satisfactory results to the 2mV/m contour and sometimes as far out as the 0.6mV/m contour. Stereo AM IBOC sounds like good FM stereo. As the AM IBOC signal degrades, it "glides" to sound like FM mono and then deteriorates from there. This may come as a big surprise to some if there is no nighttime operation. One has to ask if it will be worthwhile for stations to use the system only during the day.
Overall, the AM IOC signal is very robust, but it suffers from the usual AM problems and may limited by first- and second-adjacent problems. The NRSC committee will present its findings on April 6 at NAB for approval by the NRSC.
Acceptable Use Policy blog comments powered by Disqus
[an error occurred while processing this directive]
Today in Radio History
The history of radio broadcasting extends beyond the work of a few famous inventors.
EAS Information More on EAS
The feed provides feeds for all US states and territories.
Need a calendar for your computer desktop? Use one of ours.
Information from manufacturers and associations about industry news, products, technology and business announcements.
When Northern Community Radio set out to build a new community radio station in rural northern Minnesota 38 years ago, naysayers said that it would be broadcasting “only to a bunch of gophers
Browse Back Issues[an error occurred while processing this directive]
Also in the July Issue
- Trends in Technology: Robust IP STL
- LPFM on The March
- RF Engineering: Modern Modulation Techniques
- Field Report: Tascam TH-2000 Headphones
- Battery Maintenance: Testing and Charging