                                  MAIN MENU                                  
                                 ~~~~~~~~~~~                                 
   The main menu in PRT Calc is used, both to  change  the  various  options,
such as temperature scale, and to initiate the different modes of operation.
   Menu items are selected by using the vertical curser controls to highlight
the required item, or by pressing the appropriate  number  or  function  key. 
Once an option item has  been  selected,  the  option  can  be  activated  by 
pressing RETURN or changed by using the horizontal curser keys,  or  in  some 
cases by pressing a letter key. Brief instructions are given at the bottom of 
the screen for each item. Details of each item are as follows.
     1. Help
This item invokes the Help mode and,  basically,  displays  or  prints  these 
pages.
     2. Exit to DOS
Exits from PRT Calc to DOS or whatever shell is in use.
     3. Manual calculation
This starts the  normal  mode  of  operation  in  which  the  user  inputs  a 
temperature or resistance and PRT Calc calculates the other (depending on the
setting of the direction option). 
                                                                    (Cont...
