 term beat mean in CATV parlance? 7. Define composite triple beat. 8. A signal level is measured at 0.5 volts rms. What is the equivalent value in dBmV? 9. What dBmV level can we expect in the CATV minimum noise model? 10. When calculating S/N for TV reception on a CATV system, what is the common value of the noise weighting improvement factor? 11. If the C/N of a CATV system is 40 dB, what is the equivalent S/N? 12. There are 10 identical CATV broadband amplifiers in cascade. Each amplifier has a 7-dB noise figure. What is the thermal noise level in dBmV at the output of the tenth amplifier? Use Eq. (15.8). 13. What is an acceptable level down (below wanted signal level) for Xm? 14. A certain CATV system has 22 amplifiers in cascade with an Xm per amplifier of -89 dB. What is Xmsys? 15. Why are levels on feeder systems usually higher than mainline trunk systems? 16. What does tilt mean when discussing coaxial cable (CATV parlance)? How do we overcome the tilt? Give three advantages of a HFC CATV system over a straight coaxial cable system. What is a tap? 19. Differentiate and give advantages/disadvantages of AM and FM fiber links as part of an HFC system. 20. From a bandwidth viewpoint, why is upstream disadvantaged over downstream? 21. Why is upstream at a disadvantage over downstream from a noise viewpoint? 22. What is ingress noise? List at least four telecommunication services that the DOCSIS specification supports. 24. What is the purpose of ranging? 25. What are the two types of modulation that may be used on the upstream DOC- SIS network? List at least four different impairments we might expect to encounter in the DOCSIS upstream environment. REFERENCES 1. W. O. Grant, Cable Television, 3rd ed., GWG Associates, Schoharie, NY, 1994. 2. K. Simons, Technical Handbook for CATV Systems, 3rd ed., Jerrold Electronics Corp., Hatboro, PA, 1968. 3. E. R. Bartlett, Cable Television Technology and Operations, McGraw-Hill, New York, 1990. COMMUNITY ANTENNA TELEVISION (CABLE TELEVISION) 4. D.N. Carson, "CATV Amplifiers