ystems; PCNs CTCSS (Continuous Tone Controlled Cornea, eye, 7/9 Squelch System), 45/6, 46/9 Data windows, data truncation, 2/17 Correlation, 1/6 CTM (Clock and Tones Module), System Datagrams, packet switching, 40/12, Correlation detectors/receivers, 19/6 12, 32/10 54/12, 54/14 Correlative response codes, 28/11 CTRs (Common Technical Regulations), DataSpan, 35/5 Corti's organ, 8/5 22/19-20 DATV (Digitally Assisted TV), 57/9-11 COS (Corporation for Open Systems), CTS (Clear To Send), modems, 39/4 dBmV, dbV, dbu, dBA, 8/5 OSI, 16/8, 22/14, 22/22, 22/26 CTS (Conformance Test Services), DC line signalling, 43/4-5 Cost estimating, software, 25/18-19 22/19-20, 22/22 DC power plant design, 24/9-12 Costs, Customer perception, DC power systems see power supplies mutipoint systems, 52/11-12 telecommunications industry, 11/13 DCC (Data Country Code), 29/15 power systems, 24/15 Customer systems, power supplies, 24/14 DCCEs (Digital Cell Centre Exchanges), telecommunications industry, 11/11 CVD (Chemical Vapour Deposition), 29/11 teletraffic, 5/8-10 optical fibres, 15/9 DCD (Data Carrier Detect), modems, 39/4 Council of Ministers, EEC, 22/15 CVSD (Continually Variable Slope DCE (Data Circuit-terminating Coverage, Digitalisation), 37/8 Equipment), 54/4, 54/6, 54/7-8 CT2 cordless telephones, 49/6 CVSDM (Continuously Variable DCF (Data Communication Function), PMR, 46/5, 46/6 Slope Delta Modulation), 19/20,56/6 TMN, 16/17, 16/18 CPA (Co-polarised path attenuation), 6/19 Cyclic codes, 14/6-9 DCR (Dynamically Controlled Routing), CPS (Central Processor Subsystem), APZ Cyclic Redundancy Check see CRC subsystem, 32/16 DCS (Data Communications Subsystem), CRC (Cyclic Redundancy Check), APZ subsystem, 32/17 cordless telephones, 49/12 D2-MAC television audio, 57/8 DCT (Discrete Cosine Transform), layer2 ISDN, 44/9 D2-NTSC/525 digital composite 57/11-12, 57/25 modems, 39/11 standard, 57/13 DCX (Digital Cross Connect), PCNs, 48/6 PMR, 46/11 D2-PAL/625 digital composite standard, DDI (Direct Dial In), 29/15, 31/6 in service measurements, 