PCM/TDM TELEPHONY TRAINER

PCM/TDM TELEPHONY TRAINER
This module should have the theoretical study, supported by exercises, concerning telephony using multiplex with PCM-TDM coding. It is equipped with all the functions of a telephone exchange used in a communication system on PSTN.

Specifications

1.    Features:
i.   Basics of telephony
ii.  Telephone and power, (Pulse/DTMF) dialing
and communication signals.
iii. User interface (SLIC):
- B (Battery powered): telephone set powered by the exchange
- O (Overvoltage protection): protection against over voltages from the line
- R (Ringing): control of ringing current
- S (Supervision): detection of off-hook handset and of multi-frequency dialing pulses or tones
- H (Hybrid): conversion from 2 to 4 wires. and vice versa
- T (Testing): level of signals; characteristics of line
iv. CODEC:
- channel filter 300-3400 Hz in transmission and reception
- 64 kb/s PCM encoding/decoding
- transmission and reception Time Slot assignment and frame insertion at 2048 kbps (standard E1)
v. Simultaneous communication of more users:
- analogue multiplex: FDM
- digital multiplex: PCM-TDM
Vi.  Digital switched matrix:
Vii. CEPT interface and HDB3 coding
viii. Line interface
ix.  Line signal conversion: unipolar-bipolar
x.   Timing and exchange tones
xi. Data transmission on switched line via 2 modules mod.

2.    Technical specification:
xix.    2 telephone sets: PULSE/TONE dialing
xx.    Operating modes:
TDM E1 frame generation – 32 PCM   
channels
- Digital exchange switching
- On line with HDB3 coding
- Line simulator
- Assessment of service quality
- Bidirectional link via 2 modules   
   mod.T605/EV
 - External loop on coaxial line
iii. User jacks for the connection of max. 4   
   users for PSTN Networks, including SLIC,  
   CODEC, Digital Switch and Line Interface
iv. Display of transmission and reception time slots and frames.
v. Artificial line simulator with controls of  
    attenuation and noise generator
vi. PC able to interface with control   microprocessor
   vii. Synchronization system for displaying   
     time slots on oscilloscope
viii. LEDs of state indication:
     - Signaling: Clock Loss, BER, Frame Sync,   
       Multi-Frame Sync - Incoming calls
     - Switch Hook detection
     - DTMF binary code and Line signaling
ix. 1 interface for connection with    
     supervision PC
x. 1 supervision software for programming  
    exchange operating parameters: it must be installed in 1 PC