Ronald B. Lee

The Digital Spectrum-compatible HDTV Transmission System

The authors describe the digital spectrum-compatible (DSC) HDTV (high-definition television) System, which includes a new modulation system, a new NTSC interference filter, and reduced radiated power compared to NTSC. The system is designed to operate in the existing TV bands at 100 miles minimum cochannel distance. The NTSC interference-limited service area is unchanged. A UHF example shows that the DSC-HDTV noise-limited and interference-limited service areas are equal to those of NTSC. >

TV Multichannel Sound--Encoding and Transmission

The Electronics Industries Association(EIA) has unanimously recommended the combination of the Zenith transmission system and the dbx noise reduction system for the broadcast of TV Multi-Channel Sound(MCS). This system which has been named the Broadcast Television System Committee(BTSC) system, permits the transmission of a 50-15,000Hz stereo TV audio signal along with a simultaneous separate audio program(SAP). This paper describes the hardware needed to broadcast the BTSC system and how to adhere to the FCC OST Bulletin No. 60 specifications as well as the EIA recommended practice to be issued by. an EIA subcomittee. Figure 1 shows a block diagram of the equipment needed to broadcast the BTSC system. The BTSC composite signal appears at the output of the summer and frequency modulates(FM) the television aural carrier. The composite signal is composed of four frequency multiplexed components which are illustrated in Figure 2 along with their respective peak injection levels. The four components of the BTSC composite signal shown in Figure 2 are: