dvisory Group), 22/25 regulatory influences, 11/11-12 Teleservices, over ISDN, 44/4-5 Talk back paging, 45/6 services and technology, 11/13-18 Teletext transmission, 57/14-15 Talker echo, 30/5-6, 30/9 simplified model, 11/3-4 Teletraffic, Tandem switching, 31/6 USA, 11/6-7 Erlangs, 31/8 TB (Transmission Bridge), 31/12 Telegraph channels, multiplexed, 29/3 routing and queuing, 31/9 TC97 of ISO, 22/13 Telegraph signals, 10/5-6 service grades, 31/8 TCD (Technical Co-operation Telegraphy, invented, 11/14 theory, Department) of ITU, 22/5, 22/7 Telephone cables see Cables dynamic routeing strategies, 5/11-14 TCM (Trellis Coded Modulation), Telephone exchanges, multiple priorities and trunk facsimile equipment, 60/9 AXE system concept, 32/12-18 reservation, 5/4-6 TCP (Transport Control Protocol), 16/19, DMS System, 32/19-24 network bounds, 5/10-11 16/20-1 hierarchy, 31/3-4, 31/6-8 network models, 5/6-11 TCS (Traffic Control Subsystem), AXE System, 12 32/7-12 single link models, 5/3-6 system, 32/16 TXE analogue, 32/3-7 TUs (Traffic Unit), 31/8 Index/23 Television, statistics gathering, 61/12-13 Transition probability matrix, 4/6 bandwidth and sidebands, 57/5-6 voltage and impedance, 61/5 Transmission, colour and luminance, 57/4-5 Text to speech conversion, 37/8 2 wire/4 wire working, 29/8-10 conference by satellite, 51/18 Thermal noise, 10/10 digital video, 57/14 digital, 57/11-14 FDM, 20/10 Transmission bridge, telphones, 31/4, digital audio with, 57/15-17 repeaters, 20/21 31/10 Enhanced HDTV, 57/10, 57/23 Thermal power generation, 24/3-4 Transmission equipment power plant, 24/9 fundementals and standards, 57/3-5 Thermodynamic/information theory Transmission line loss, microwaves, 50/5 HDTV, 57/10 comparison, 4/3-5 Transmission loss, 30/4, 30/9, 30/13 NICAM, 57/12, 57/16, 57/17 Thin overlay networks, SDH, 42/25 Transmission planning, 30/1-14 signals, 10/6 Thin route satellite telecommunications, analogue telephony, 30/3 systems, 57/6-10 51/17-18 delay, echo and stability, 30/5-7, by country, 57/6 Three-way calling, 330/