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Convergence Technology. MODULE 2 - LEARNING OUTCOME 5 Describe signaling and its importance to telecommunications and differentiate various signaling techniques involved in telephony. Voice Telephony Fundamentals. What Makes the Telephone Work? The hook switch The Microphone The Speaker
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Convergence Technology MODULE 2 - LEARNING OUTCOME 5 Describe signaling and its importance to telecommunications and differentiate various signaling techniques involved in telephony.
Voice Telephony Fundamentals • What Makes the Telephone Work? • The hook switch • The Microphone • The Speaker • ECHO
Speaker Microphone To Wall Jack Hook Switch Anatomy of the phone
Touchtone Keypad Speaker Duplex Coil Ringer Microphone To Wall Jack Hook Switch Telephone components with duplex coil and touch-tone keypad
Green wire Red wire Resistor 9 Volt Battery 300 Ohm Component Configuration
Vibrating Diaphragm Electric Contact Carbon Granules Wires Electric Contact Telephone Carbon Microphone
Diaphragm Dust cap Suspension Magnet + - Voice coil How a speaker works
Voice Telephony Fundamentals • Wires and Cables • Residential Cabling • The Telephone Network cabling • Signaling and Transmission • Analog Signals • Digital Signals
To phones inside house Entrance Bridge Ground wire From the Central Office Entrance bridge
Roadside wiring concentrator Typical phone company boxe (wiring concentrator) that you have seen by the side of the road
Residences Residential cabling
Voice Telephony Fundamentals Waveform Sine Wave Anatomy Frequency Wavelength Amplitude Signal Phase
One cycle One Second One Hertz a t a V = Voltage t = time A = Amplitude 00 900 1800 2700 3600 One cycle per second = one Hertz Anatomy of a sine wave
1 cycle per second (1 Hz) One Second 2 cycles per second (2 Hz) 4 cycles per second (4 Hz) Cycles per second
Unipolar Bipolar Nonreturn to Zero Bipolar Return to Zero Manchester Differential Manchester Digital Signal types
Analog Phone Digital Transmission (Digital Data Lines Analog Phone Codec Analog Signal Digital Signal The Codec
Dallas Boston Central office A/D conversion Central Office D/A conversion Analog to Digital to Analog
Voice Telephony Fundamentals • Local and Long-Distance Calling • The Protocol for Making a Phone Call • DTMF (Dual-Tone MultiFrequency)
Voice Telephony Fundamentals • Transmission Lines • Attaching Transport Devices • Circuits • Two-Wire Circuits • Four-Wire Circuits • The Effects of Attenuation When Using Two-Wire or Four-Wire
Dallas Boston Central office A/D conversion Central Office D/A conversion Analog to Digital to Analog
Twisted Pair Outer Jacket Plastic insulation Outer Jacket Foil shield Eight wire - four pair Twisted Pairs Braided shield Four wire – two pair Two-wire and four-wire pairs
Receive Transmit Transmit Receive Customer Site Carrier Four-wire circuit
Voice Telephony Fundamentals • Lines and Trunks • CPE Switches • Network Switches • Channels • Virtual Circuits • Flavors of Virtual Circuits • Network Connections
International Gateway Core Network Class 4 Switches Interexchange Trunks Class 5 Switches Local Loop Local Exchange Trunks Subscriber Lines CPE PBX PBX Residential Phones Business Phones CPE lines, trunks, switches
Voice Telephony Fundamentals • Bandwidth • Getting more out of a wire pair • Bandwidth and the Electromagnetic Spectrum • Electromagnetic Spectrum
The anatomy of an analog voice channel Frequency multiplexed voice signals Bandwidth of a voice channel
Questions: Feel free to contact the creator of this material • Peter Brierley, Professor, Collin County Community College, brierley.peter@gmail.com This material is based upon work supported by the National Science Foundation under Grant No. 0402356. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation