elephone networks, 29/4-5 packet capture, 61/13-15 Transfer functions, 2/11-12 Trunked mobile radio, 46/5-7 PCM, 61/3 Transform coding, 57/25 TSC (Trunking System Controller), PMR, photometric, 7/5-6 Transformers, impedance matching, 33/5 protocol, 61/14-19 Transforms, TSS (Technical Support Service), 22/19 pulse shape, 61/4 Fourier see Fourier analysis TSS (Trunk and Signalling Subsystem), radiometric, 7/4, 7/6-7 Laplace see Laplace transforms AXE system, 32/16 in service standards, 61/11 Markov equations see Markov TST (Time-Space-Time) switching, 31/14 software, 25/14-17 methods, queuing theory, 3/8-12 TT&C (Telemetry, Tracking and Index/24 Command) antenna, 17/14 V.32 modems, 39/6-7 transmission, 57/20-1 TTC (Telecommunications Technology V.42 modems, 39/9 videophony and videoconferencing, Committee) Japan, 22/26 V series transmission standards, 39/5-9 57/27, 57/29-34 TTF (Transport Termination Function), VAD (Voice Activity Detection), PCN, over PSTN, 57/33 SDH, 42/17 48/11 see also Television TTM (Trunk Test Module), System 12, VADIS (Video Audio Digital Interactive Virtual circuits, packet switching 32/10 System), 57/3 see SVC TUA (Telecommunications Users Valve regulated sealed acid battery, 24/13 Vision see Optics and vision Association), 22/23 VANS (Value Added Network Services), Viterbi decoding, 14/10 Tubular element battery cells, 24/13 EDI, 38/3, 38/6, 38/7 VLCs (Variable Length Codes), 57/25 TUGs (Tributary Unit Groups), 42/11-12 Varicap controlled filters, 46/3 VLR (Visitor Location Register), 32/18, Tuned circuit discriminators, 18/9 VC (Virtual Call), packet switching, 40/12 47/10, 47/13, 48/8 Tunnel diode amplifiers see TDA VC (Virtual Channel), ATM, 41/11 VLSI (Very Large Scale Integration), 21/8 TUs (Traffic Units), 31/8 VCC (Virtual Channel Connection), exchanges, 32/7 TUs (Tributary Units), SDH, 42/10, ATM, 41/9 Voice channel performance, analogue and 42/11-12 VCI (Virtual Channel Identifier), ATM, digital, 50/11 TV see Television; Video 41/4, 41/5-6, 41/11 Voice compression, 56/6 TVE (Tran