Example using Arial font "letter A with dot below"

Open MS WordPad (not Word)
   Set WordPad to Arial Font
Key Sequence:
   Set Numeric Num Lock = ON
   Hold down ALT key while pressing the following:
   Press Numeric Plus Sign key
   Press Numeric 7 key
   Press Numeric 8 key
   Press Numeric 4 key
   Press Numeric 1 key
   Set Numeric Num Lock = OFF
The above sequence can be programmed onto Martian Keyboard key
   for fast entry of the character.

1. 7841 is the decimal value of the unicode character.
2. WordPad is one app that accepts the control sequence above.
   Other apps may use different methods , -should be googled for help.
   e.g. Result site: http://www.georgehernandez.com/h/xComputers/CharacterSets/Shortcuts.asp
3. 7841 was found by internet search: "letter A with dot below"
   Result site: http://www.fileformat.info/info/unicode/char/1ea1/index.htm
4. Many other fonts may also contain letter A with dot below.
   E.g. list is at: http://www.fileformat.info/info/unicode/char/1ea1/fontsupport.htm
5. Once you can control the unicode character in your document by manually
   typing the key sequence, then program the sequence into a Martian Keyboard key
   for simple single key press.
6. If you need a different font that contains the special characters you need, then
   there is a web site http://www.alanwood.net/unicode where there are many resources
   to understand unicode and download hundreds of free unicode fonts.