58-001

Telephone and Interface Signalling, speech circuits and the immediate interface at the switching centre are examined. The use of a high quality, commercial telephone hybrid circuit in the subscriber’s line interface (SLIC) allows useful measurements to be made.

TDM/PCM Principles
Allows the study of the principles TDM/PCM. It is based on the use of standard telephony devices but also uses special circuits to demonstrate the effects of variable sampling rate, bit rate and filtering. PAM is used to demonstrate the concept of taking short samples to represent a continuous waveform. TDM is demonstrated by multi-channel PAM which demonstrates the principle of sharing a single physical link between different communication channels.
Features

• Uses Discovery Software
• Uses commercial telephony components

Curriculum Coverage

• Telephone Signalling
• Telephone Speech
• Subscriber’s Line Interface Circuit (SLIC)
• Dual Tone Multi-Frequency (DTMF) Signalling
• SLIC Hybrid
• Testing
• TDM/PCM Principles
• Sampling
• Multiplexing (TDM)
• Pulse Code Modulation (PCM)
• Companding
• Filtering