Thursday, August 11, 2005
HD Radio means HIGH DESTRUCTION-Fewer Stations!
1 Billion Radios in North America will be obsolete!
The NRSC-5 HD radio specification submitted to the FCC puts the digital signal on 2 channels on both sides of the existing analog signal, occupying a total of 5 channels. This can be clearly seen on spectrum analyzer photographs, from engineering studies, and even in the NRSC-5 HD proposal itself.
For example, here in Philadelphia, assigned channels of 103.9 and 104.5 are only 3 channels apart, (there are only 2 channels between them). The two signals both originate only hundreds of feet apart from antennas in the Roxborough antenna farm. There are only 2 (guard band) channels between these 2 existing analog stations. It is proposed to put the part of the digital signal from both stations on the same 2 intervening channels.
Under NRSC-5 HD radio, the 2 digital signals from Philadelphia stations assigned to 103.9 and 104.5 will overlap and jam each other. Digital signals from the 2 stations that will be on the guard band channels 104.1 and 104.3 will overlap with destructive interference. The 104.1 and 104.3 frequencies are necessary to prevent the signals from combining in the radio receiver causing interference.
This is not an unusual circumstance with NRSC-5 HD radio. Popular stations in Wilmington, Trenton, Reading, suburban Philadelphia, New Jersey will be jammed and, in return cause jamming, in large destructive interference zones, where the 2 digital signals will mix and interfere. This will be dominant in interference zones created in nearby suburban areas. In these interference zones neither station's digital signal will be clearly received. Traveling between these cities and listening to either digital station will be difficult if not impossible.
A large interference zone will be created in northern New Jersey by digital signals emitted by WBEB 101.1 Philadelphia and WCBS-FM 101.1 New York. Popular station, New Jersey 101.5 will be jammed by the new digital signals and in addition the 101.5 digital signal will jam the two 101.1 signals.
This will be common in large metropolitan and suburban areas where most listeners are located.
The FCC is aware of the jamming, but is being influenced by well financed political lobbying efforts by organizations and corporations who will benefit from the sale of the expensive new digital radios.
By causing digital interference to existing analog FM and AM radios and stations, the NRSC-5 promoters hope to obsolete the over 1 billion AM and FM radios in North America, and influence people to buy their expensive, proprietary new HD radios.
NRSC-5 HD digital radio system uses the guard bands between stations for the new digital signals, interfering with all existing analog FM and AM radios.
Impartial engineering studies clearly warn of the impending digital disaster if the seriously flawed NRSC-5 HD radio system is adopted.
Fortunately, there are alternative proposed digital FM and AM broadcasting systems, that are compatible with our current analog radios, and don't have the serious defects of NRSC-5 HD radio.
The NRSC-5 HD radio iBiquity system needs to be sent back to the drawing board and completely revised.