function nchar(c) ! Convert ascii number, letter, or space to 0-36 for callsign packing. character c*1 n=0 !Silence compiler warning if(c.ge.'0' .and. c.le.'9') then n=ichar(c)-ichar('0') else if(c.ge.'A' .and. c.le.'Z') then n=ichar(c)-ichar('A') + 10 else if(c.ge.'a' .and. c.le.'z') then n=ichar(c)-ichar('a') + 10 else if(c.ge.' ') then n=36 else Print*,'Invalid character in callsign ',c,' ',ichar(c) call exit(1) endif nchar=n return end function nchar