INTERCOM

  An  Electronics  private  Branch  Exchange  (or  EPABX)   is probably the most important item of tele-communications equipment that a company or other organisation acquires. Its basic function is twofold : first, to connect a number of telephones instruments to  the  public  telephone  network, without  having  a  separate telephone  number  for  each  person  in  the  organisation;  and secondly to make it possible to communicate internally within the organisation;  and  secondly to make it possible  to  communicate internally  within the organisation without incurring local  call costs.

PBAX,in which there is a switchboard, but this is used  to connect  only calls coming in form the public  network.  Internal calls,  in most cases, outgoing calls are dialled by users,  from their  telephone  instruments. Also, the switch board of  a  PBAX tends to be simpler to operate.

A special variation of a normal PABX arrangement is to have the  system equipped for Direct-Dialling-in (or DDI for  short  – sometimes  alternatively referred to as direct  in-dialling –  or DID).  With  DDI  the caller from the  public  network  can  dial straight  through  to the telephone exchange he  wishes  to  call within  the  PBAX,  without having to go via  the  operator.  the caller  dials the DDI prefix for the organisation,  followed  the extension number he wants. For example, If the DDI prefix is  246 a  caller dials 246 2121 to call extension 2121. If he  does  not know  the extension, only then does he call the PABX operator  or the general inquiry number published in the telephone  directory. this might be, for instance 246 1000.

Most  PBAX’s  can be converted from normal  working  to  DDI without  a clossal amount of re-equipment. However, with the  TXE range  of public telephone exchanges, small groups of  DDI  lines are  easier  to  provide than tow was the  case  with  the  older stronger type exchanges.

A  PAX,  or  private   Automatic  Exchange,  should  not  be confused  with  a PABX. a PAX is in no way  connected  to  public network and is installed purely for internal communication. It is unusual  to have both a PAX and PABX sine the PABX  provides  all the facilities of a PAX. however a few organisation have a PAX to serve  areas which have no need for making or  receiving  outside calls; PAXs are generally cheaper than equipment PABX.

1.   INTRODUCTION
2.   USES AND APPLICATION
3.   MARKET TRENT
4.   PRESENT MANUFACTURERS OF EPABS
5.   PROPERTIES
6.   PABX TECHNOLOGY
7.   SUPPLEMENTARY FEATURES  AT PABX’s
8.   THE CONVERNTIONAL SOLUTION
9.   MANUFACTURING OF EPABX
10.  DEFINITIONS
11.  SPECIFICATION
12.  MINIMUM INFRASTRUCTURE FOR MANUFACTURE
OF C-DOT PABX OF 20,000 PORTS PER ANNUM
13.  KNOW-HOW FEE AND ROYALTY
14.  MANUFACTURERS OF PABX / PBX (foreign)

APPENDIX – A :

1.      COST OF PLANT ECONOMICS
2.      LAND & BUILDING
3.      PLANT AND MACHINERY
4.      FIXED CAPITAL INVESTMENT
5.      RAW MATERIAL
6.      SALARY AND WAGES
7.      UTILITIES AND OVERHEADS
8.      TOTAL WORKING CAPITAL
9.      COST OF PRODUCTION
10.      PROFITABILITY ANALYSIS
11.      BREAK EVEN POINT
12.      RESOURCES OF FINANCE
13.      INTEREST CHART
14.      DEPRECIATION CHART
15.      CASH FLOW STATEMENT
16.      PROJECTED BALANCE SHEET