CODITEL Telephony Systems Unit
The CODITEL unit is based on a digital or temporal commutator enabling the study of emission in any order on the channels of an outlet multiplex. The samples that are shown in a certain order, on channels of an inlet multiplex.
CODITEL is a digital circuit commutation unit for didactic purposes. Its structure is like a temporal commutator structure with two MIC ways, one inlet way and one outlet way. Basically, it follows the recommendation of the CCITT and of Telephony.
This unit consist of the following parts: interfaces (connection with the outer world), internals, digital connection network and control system:
Interfaces: It consists of four user line circuits, two lines for tone terminals (multifrequency) and two lines for pulse terminals (decadic), made in different ways:
- The multifrequency circuits are hybrid integrated circuits carrying out all the basic functions of a line circuit.:
- The decadic circuits, where all their structure is mounted discrete components.
- The four line circuits are compatible with commercial user apparatus.
Internals: The unit has four number receiver, two of them are pulse receivers (decadic) and the other are tone receivers (DTMF), assigned to a specific line. It has a time base that supplies the appropriate temporization for the whole system and a digital tone generator.
Digital connection network: The connection network is a temporal commutation matrix, made with memories. Its architecture is like the one with a sequential writing and asynchronous reading commutator.
Control system: The control is carried out by a program stored in the computer (PC), and it is executed under the windows operating system 2000 or higher.
The communication between the computer (PC) the interface through serial RS232 protocol.
This Computer Controlled Unit is supplied with the EDIBON Computer Control System (SCADA), and includes: The unit itself + aControl Interface Box + a Data Acquisition Board + Computer Control, Data Acquisition and Data Management Software Packages, forcontrolling the process and all parameters involved in the process.
Exercises and guided practices
GUIDED PRACTICAL EXERCISES INCLUDED IN THE MANUAL
- To study the main actions and signals involved in a digital commutation.
- To study the dynamic channel assignment and temporal switching.
- To study the standards for audio conversion.
- To establish of a communication between some channels step by step.
- Visual monitoring of the main states that a line goes through during a call.
- To configure lines as only receiver, transmitter, receiver/transmitter.
- To test of the conversion from 2 to 4 wires.
- To study the electric stages when the user makes actions over the telephone.
- To study the signal involved when dialing by pulses.
- To study the signals involved when dialing by tones.
- To study the tone signal.
MORE PRACTICAL EXERCISES TO BE DONE WITH THE UNIT
- Many students view results simultaneously.
- To view all results in real time in the classroom by means of aprojector or an electronic whiteboard.
- The Computer Control System with SCADA allows a realindustrial simulation.
- This unit is totally safe as uses mechanical, electrical/electronic,and software safety devices.
- This unit can be used for doing applied research.
- This unit can be used for giving training courses to Industrieseven to other Technical Education Institutions.
- Several other exercises can be done and designed by the user.