Showing papers in "IEEE Transactions on Broadcasting in 1969"
TL;DR: The K factor of a 2T pulse waveform is usually determined by fitting the waveform into an oscilloscope mask at prescribed deflection factors, but quite often a mask is not available, or a picture of the wave form is given with amplitude and time coordinates only, and a method is presented which permits the K factor to be determined algebraically.
Abstract: The K factor of a 2T pulse waveform is usually determined by fitting the waveform into an oscilloscope mask at prescribed deflection factors Quite often a mask is not available, or a picture of the waveform is given with amplitude and time coordinates only For these cases a method is presented which permits the K factor to be determined algebraically
5 citations
TL;DR: The isocon camera tube as discussed by the authors is a development of the image orthicon, but produces a positively modulated output signal, which can be set to discharge highlights without materially affecting low light performance, thus giving very wide dynamic range.
Abstract: The isocon camera tube is a development of the image orthicon, but produces a positively modulated output signal. In the image orthicon, the output signal has negative modulation and the detection of weak signals is limited by the shot noise in the large return beam current. The isocon overcomes this limitation as the return beam current is small for small signals, and the signal-to-noise ratio is maintained to very low light levels. The scanning beam current can be set to discharge highlights without materially affecting the low light performance, thus giving very wide dynamic range.
2 citations
TL;DR: In this article, a critical analysis of all these factors with possible tradeoffs is presented and the station coverage is computed based on the present available FCC (50, 50) curves and a computer program.
Abstract: In the selection of a transmitting antenna, factors such as power gain, height above terrain, horizontal pattern directivity, amount of null fill, and beam tilt of the vertical pattern have to be taken into consideration to best satisfy the equipment availability and intended market coverage. A critical analysis of all these factors with possible tradeoffs is presented and the station coverage is computed based on the present available FCC (50, 50) curves and a computer program. A new variable, the maximum possible antenna gain to guarantee a minimum signal level over a certain area, is introduced. A set of curves relating the maximum possible antenna gain to distance, maximum radiated power, antenna height, and signal level is developed for the three TV bands.
2 citations
TL;DR: The specifications required to guarantee proper performance of a VHF television modulator or demodulator are relatively well-defined, but measurements associated with the specifications are somewhat complex and require techniques and equipment not normally available to Community Antenna Television (CATV) system engineers.
Abstract: The specifications required to guarantee proper performance of a VHF television modulator or demodulator are relatively well-defined. Measurements associated with the specifications are somewhat complex and require techniques and equipment not normally available to Community Antenna Television (CATV) system engineers.
2 citations
1 citations
TL;DR: In this article, the authors suggest methods of progranmning instructional broadcast satellites to reduce the cost of education, where a student can answer questions by resetting dials before him to choose the block he hears, and if he answers correctly, he branches ahead; otherwise, back. But the advantages of radio programnming are that, with no ground-to-satellite feedback, the student can: 1) be obliged to actively respond, 2) have feedback on his accuracy, 3) begin at his own level, 4) advance at a own pace, 5
Abstract: Half the cost of education is that of students' time; this paper suggests methods of progranmning instructional broadcast satellites to reduce this cost. For fixed satellite ERP and ground station cost, 200 audio channels could replace a TV channel. If a 100-hour course were broken into 30-minute blocks, each could be transmitted simultaneously. Students would listen through earphones and follow the course in illustrated workbooks. At the end of a block, a student would answer questions by resetting dials before him to choose the block he hears. If he answers correctly, he branches ahead; otherwise, back. Continuous 12-year sequences of math, science, and verbal skills instruction could be available. The advantages of radio programnming are that, with no ground-to-satellite feedback, a student can: 1) be obliged to actively respond, 2) have feedback on his accuracy, 3) begin at his own level, 4) advance at his own pace, 5) miss school and resume where he left off, and 6) spend extra time (weekends or evenings) without waiting for his class. Additional sections of the paper deal with frequency allocation, interference, and ground station design.
1 citations
TL;DR: Subjects now under discussion are methods of measurement of linear waveform distortion including the use of sine-squared techniques; 2) definition and measurement of dynamic gain; and 3) measurement of impedance errors using the return loss principle.
Abstract: The Video Signal Transmission Subcommittee 2.1.4 of the IEEE Group on Broadcasting is actively engaged in preparation of standards dealing primarily with the transmission and monitoring of baseband video signals. Subjects now under discussion are 1) methods of measurement of linear waveform distortion including the use of sine-squared techniques; 2) definition and measurement of dynamic gain; and 3) measurement of impedance errors using the return loss principle. The present status of this activity is reviewed and similar work done by other organizations such as the CCIR and EIA is surveyed.
1 citations
TL;DR: Analysis of the carriage of signals in the presence of a strong, ambient, co-channel field intensity generally results in interference between the desired signal delivered by the cable and a signal picked up by leakage either in the receiving set or the cable itself.
Abstract: The carriage, on cable television, of signals in the presence of a strong, ambient, co-channel field intensity generally results in interference between the desired signal delivered by the cable and a signal picked up by leakage either in the receiving set or the cable itself An analysis of this phenomenon suggests various techniques for detecting and measuring the interference
1 citations
TL;DR: The statistical approach employed in evaluating performance from data collected by regular sampling of key parameter values, and the subjects of confidence levels and of user and supplier risks when evaluating performance are discussed.
Abstract: The paper discusses the method used by the CBC to a) ascertain that the quality of long-line transmissions is maintained at the required high level, and b) assist in the control of short-term deviations of transmission performance It details the statistical approach employed in evaluating performance from data collected by regular sampling of key parameter values The subjects of confidence levels and of user and supplier risks when evaluating performance are also discussed
1 citations
TL;DR: The requirements for a fully satisfactory and reliable CATV system are analyzed and objective technical specifications which should be met are set forth by the equipment manufacturer and the system operator.
Abstract: Television distribution by cable is rapidly coming of age as a widely accepted public service. Equipment is now becoming available which will do much to bring about necessary improvements in system performance, life, reliability, and operating costs. This paper analyzes the requirements for a fully satisfactory and reliable CATV system and sets forth objective technical specifications which should be met by the equipment manufacturer and the system operator. References for requirements based on subjective evaluation are given.
TL;DR: In this article, a simple expression is derived which allows the quantitative evaluation of the unwanted effect of spurious AM caused by the resonators of the vision?sound combiner, and some considerations are made regarding the mechanical design criteria to be followed in order to improve it.
Abstract: The FM sound signal of a broadcasting TV transmitter is usually affected by spurious AM caused by the resonators of the vision?sound combiner. A simple expression is derived which allows the quantitative evaluation of this unwanted effect. Since the frequency stability of the resonators is the only factor which falls within the control of the designer, some considerations are made regarding the mechanical design criteria to be followed in order to improve it.