                         TRACK INDICATOR DOCUMENT

     All  the  details  given for the Track Indicator are for  a  520 STFM 
(Revision  B  Board)  only,  but should not be too  different  from  other 
models.
     No  contructional  details  have been given  as  everybody has  their
own preferred methods, i.e. Veroboard, Breadboard, Etching Printed Circuit 
Board with Transfers, Photo Etching etc.
     The indicator can be connected in a variety of ways depending on  how 
technically  minded you are. If you only have a single internal drive  you 
would have no need to do the printed circuit board modification and  could 
just  plug the indicator into the external drive socket,  which means  you 
would  also  have no need to connect the DRIVE 1 signal  to  the  external 
drive socket. If you have an external drive as well you would need to make
sure all the second drive signals passed through the indicator circuit/box
and that the circuit board modification is done. Or  you  could  just wire
the circuit directly to the ST circuit board, but this would require  that
you know what you are doing and have taken the proper safty precautions.
     The  power  reqirements for the circuit,  which depends on  how  many 
LED's are lit at the time, varies in use from approximately 100mA to 130mA
so a 150mA +5V power source should be adequate. This again can be obtained
in a variety of ways, from a 9V battery via a  +5V  regulator such as  the 
UA78M05UC  (MAPLIN  PART NUMBER QL28F),  or perhaps from the  ST  Joystick 
port, or any of numerous other ways.
     The  Track  Indicator Details are provided in the form  of  High  and 
Medium  Resolution  COMPRESSED  DEGAS  pictures, although the  printout if
needed is  much  better from  High  Resolution as  the  Medium  Resolution
pictures are PICTURE SWITCHER converted from the High Resolution pictures.
     Also included for those lucky  enough to have  PCB  DESIGNER, are the
necessary PCB DESIGNER files to produce a printed circuit board layout.
     This disk should contain the details in the following files :-

          ST_MOD  .PC3   Shows modification to 520 STFM circuit board
          ST_MOD  .PC2   

          ST_CCT  .PC3   Shows 520 STFM external drive socket circuit
          ST_CCT  .PC2   diagram

          TI_CCT  .PC3   Shows Track Indicator circuit diagram
          TI_CCT  .PC2

          PARTLIST.PC3   Shows Track Indicator parts list
          PARTLIST.PC2

          PARTPINS.PC3   Shows pins on some components
          PARTPINS.PC2

          TRK_INDI.BRD    Files for PCB DESIGNER
          TRK_INDI.CRT
          DEF1    .LIB

          TI_TEXT .DOC   This document in ASCII text
