Open a printer emulation session.
From the Setup menu, choose View Settings.
This setting specifies the number of characters to print per inch.
If Print Proportional Chars per Inch is set to Yes, Printer Chars Per Inch is disregarded. In this case, the number of characters printed per inch is determined by the current printer font.
As you change Printer Chars Per Inch, Printer Chars per Line may change as well; more characters per inch means more characters on a line (assuming the left and right margins don't change).