Required hardware:

1.) A radio with discriminator output. (Note some scanners do not have
    a stable VFO and will add what looks like a PL tone to a signal that 
    does not have one.)

2.) A sound card is required to use all functions of XMIT_ID.

3.) A small attenuator circuit that goes between the radio's discriminator 
    output and the sound card microphone input.

4.) A 386SX 16 MHZ or better with 640K of ram and a large hard drive for  
    unattended use.  About 80 MEGS a day is needed on large systems.  If you 
    are going to keep a finger print on each user you will need about 30K of
    hard drive space per user to cover multiple rigs.  
 
 
 _________
 | Radio | Discriminator
 |       |    output           100 K Audio Taper
 |       |------------------/\/\/\/\/\/\/\/\/\/\/\-------GND
 |       |                          /^\                   
 |       |                           |                   
 |_______|                           |          1k              
    |                                |_______/\/\/\/\/\/\______MIC input
    |                                                          on sound 
    |                                                   _______card.
   GND                                                 |
                                                       |
                                                      GND

  Put the pot in a metal case and use shielded cable.  Keep wires as short as
  possible.  You may use Toroid rings to keep computer noise from the radio.

  A COR (Carrier Operated Relay) interface is not required but can be helpful
  in recording signals with PL tones.  This method uses hardware control to
  record.  You must find COR in the receiver and bring it out with the
  discriminator.  Please refer to the service manual for help in locating 
  this point in the radio.  The output must be brought out active low.
  Taking either fire control button on the joystick port low will cause the
  program to start recording when in the 'R' mode (internal record mode).

Game Port ===========

DB15

        1       +5 VDC
        2       button 1                    Bring this pin low.. for COR
        3       position 0  (X Coordinate)
        4       ground
        5       ground
        6       position 1  (Y Coordinate)
        7       button 2
        8       +5 VDC                  JOYSTICK "A"
